Identical coefficients estimated in Poisson vs Quasi-Poisson model

In modeling claim count data in an insurance environment, I began with Poisson but then noticed overdispersion. A Quasi-Poisson better modeled the greater mean-variance relationship than the basic Poisson, but I noticed that the coefficients were identical in both Poisson and Quasi-Poisson models.   If this isn't an error, why is this happening? What is the benefit of using Quasi-Poisson over Poisson?  Things to note:   The underlying losses are on an excess basis, which (I believe) prevented the Tweedie from working - but it was the first distribution I tried. I also examined NB, ZIP, ZINB, and Hurdle models, but still found the Quasi-Poisson provided the best fit.  I tested for overdispersion via dispersiontest in the AER package. My dispersion parameter was approximately 8.4, with p-value at the 10^-16 magnitude.   I am using glm() with family = poisson or quasipoisson and a log link for code.  When running the Poisson code, I come out with warnings of "In dpois(y, mu, log = TRUE) : non-integer x = ...".   Helpful SE Threads per Ben's guidance:


Scrolling/content area issues on iOS 8.4

I'm using Safari on an iPhone 6, iOS 8.4 (yes, it's time to upgrade, but then how would we find these fun bugs?).  In the new mobile chat, the bottom part of the content area is often outside the bounds of the device and can't be scrolled to.  This is what I normally see when opening a room list: . And this is what happens if I take a screenshot while still touching the screen after scrolling to the bottom of the list: . (The second I let go, the list "bounces" back to what you see in the first screenshot.)  Entering a room typically looks like this: .  So, it appears that this behaviour occurs when Safari is still showing the browser navigation controls. There's no apparent way to dismiss those controls - scrolling or tapping anywhere on the screen doesn't do it - and they don't disappear on their own. I've been able to make it go away sometimes by scrolling until the input message box is in view, but then the top part of the page goes AWOL and there's no bringing it back: .  If I reply to a specific message, the input box at the bottom sticks around like it should, and the messages scroll fine behind it... but the header disappears completely (similar to , but without even a sliver of blue at the top).


"Set document metadata failed" when I run sudo gedit

I have upgraded 14.04 to 16.04 . Now I am trying to open the gedit from terminal by passing the command:    sudo gedit /some/where/file.txt   but it is throwing an error stating that:    (gedit:2090): Gtk-WARNING : Calling Inhibit failed: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown:   The name org.gnome.SessionManager was not provided by any .service files**   However, it is opening the file. When I try to save any modification then it is showing this error after saving the file:    (gedit:2090): WARNING : Set document metadata failed: Setting attribute metadata::gedit-position not supported   I am not getting why this is happening in 16.04 only; it was not on 14.04.


What items look like scrappable junk, but can't be scrapped?

Almost everything you can pickup in Fallout 4 can be scrapped for components, but not quite everything.   Some things clearly are not junk, even though they can be scrapped. As far as I'm aware, this includes all non-legendary weapons and armor and mods when attached, so ignore those. Some things are pretty clearly not junk, and cannot be scrapped. As far as I'm aware, this includes aid items, so ignore those. If you know an exception to these broad strokes, please mention it.  This leaves Misc items. I think some of these can be broken down (in workshop mode), but many cannot. Folders, for instance, .  What items are in this category?   An exhaustive list would be nice if it's short enough, but the point is to avoid picking up things I can't scrap, so focus on ones one is likely to see, and on describing them in a way that can be remembered.


How can one estimate $(1/2)\int_{-\pi}^{\pi}|D_N|dx$,here DN is the Dirichlet kernel

The Dirichlet Kernel $$D_N =\frac{\sin(N+1/2)x}{\sin x/2}$$ How to show this  $$\frac{1}{2\pi}\int_{\pi}^{\pi}|D_N|dx=\frac{4}{\pi^2}\log N+O(1)$$


Reputation recalculation when downvoted post gets deleted lets users find out who downvoted them

The other day one of my posts got a downvote. For reasons, I kinda knew who this downvote came from so I opened up their profile page in another tab, deleted my answer, and that user suddenly got a +1. Yes, it was him/her! Not that I really care, my answer was not particularly good/useful anyway, but it's clear that this "trick" should be blocked somehow. How could this be prevented?  Note: I didn't see the +1 in their rep. tab, because that is not visible to other users. What I saw is that their total reputation increased by one point. .  I do not suggest any specific solution here, I just want to discuss this ability to find who downvoted and its implications. I would also like to hear possible solutions.


Does there exist an $n$ such that all groups of order $n$ are Abelian?

I know that all groups of order $\leq$ 5 are Abelian and all groups of prime order are Abelian. Are there any other examples? If so is there something special about the orders of these groups?


Is OS X on VirtualBox on Windows suitable for iOS app development using Xcode?

I am trying to install OS X on VirtualBox VM on Windows 7, but it is giving me a message that "hardware acceleration" is missing on my PC.  How can I deal with this problem? …and is this suitable for iOS app development using Xcode?


Is the link between shadows a refraction of the light?

When two objects in the sunlight approach, if you look at their shadows, they form a link when they are really close, is that an example of refraction? If so, is it the same as the refraction we see on the water (light traveling in a diferent medium)? The different medium being the edje of the objects.


Why swap1 method gives false swap & swap2 method gives real swap?

In the following code, I want to swap two objects but the first method (swap1) which swap the object reference variables of the two objects doesn't work while the other method (swap2) which swaps the values of the objects' data fields x.radius & y.radius work properly so what's the problem with the first method? why when I swapped the two reference variables of the two objects, they didn't refer to each other?  public class Main {     public static void main(String [] args) {         TestCircle circle1 = new TestCircle(1);         TestCircle circle2 = new TestCircle(2);         swap2(circle1,circle2);         System.out.println("After swap2: circle1 = " +         circle1.radius + " circle2 = " + circle2.radius);      }      // false swap     public static void swap1(TestCircle x, TestCircle y){         TestCircle temp = x;         x = y;         y = temp;     }      // real swap     public static void swap2(TestCircle x, TestCircle y){         double temp = x.radius;         x.radius = y.radius;         y.radius = temp;     }  }  class TestCircle {     double radius;      TestCircle(double newRadius){     radius = newRadius;     } }


Python - difference between 'a' and "a"?

I have been always mixing these two notations, regarding them both as a string in Python.   What are the differences between them?   Under what circumstances can we only use one of them?


Infinite sequence of derived sets $A', A'', A''',...$

I'm studying this book:  and I'm just starting to chapter on ordinal numbers (still have no idea what they are), and the introduction goes: "Cantor considered the sequence of sets obtained by starting with $A$, finding its derived set $A'$, then the derived set $A''$ of $A'$, and so on. Cantor wished to continue his construction in the case when none of $A', A'', A'''$, etc., was empty. He ultimately hit on the idea of constructing a set $A^\infty$ as the intersection of $A', A'', A''',...$. He then made repeated use of the derived set construction on this set to give $A^{\infty+1}, A^{\infty+2}, ...$ and in the case when non of these was empty, he again took their intersection, to give $A^{\infty+\infty}$ and so on." I've never studied topology and I got pretty lost on this, I just googled what a derived set is and a looked for a couple of examples, the only example I found for a set $A$ to have infinite non empty derived sets $A', A'',...$ etc was the set $(0, 1),$ whose derived set is $[0, 1]$, whose derived set is $[0, 1]$ etc. The intersection of all this $[0, 1], [0, 1]', [0, 1]''$ will always be non empty, so i can't really see what Cantor was trying to achieve. Could you guys please give me a simple example (since I'm just starting to study math seriously in general) of a set $A$ whose derived set $A'$ is different than $A$ and whose derived set $A''$ is different than $A'$ etc infinite times even just many times so I can at least see intuitively what Cantor was trying to do? Thank you!


Any good blogs/books or roadmap to learn Development in salesforce?

Can someone help me learning Salesforce development with good recommendation of blogs or books.  Thanks


Is there any episodes between Naruto and Naruto Shippuden?

I've just finished watching the last episode of Naruto(220), and when I started watching Shippuden the first episode seemed odd, I have only watched the first 5 minutes of that episode and didn't think it was right, it was naruto and sakura running through some kind of dungeon trying to find Sasuke, they eventually heard an explosion and rushed there, they found Sasuke standing on top of a small crater. That's about as far as I got. My question is, am I on the correct episode or am I missing some episodes? Or perhaps did I start on the wrong one?


In Fairy Tail chapter 425, during the Avatar arc, Sting has become a "little" chunky.    Might it be a new move or something?


Evaluation of $\int \frac{\sqrt{\sin ^4x+\cos ^4x}}{\sin ^3x \cos x }dx$

Evaluate the following integral:  $$\int \frac{\sqrt{\sin ^4x+\cos ^4x}}{\sin ^3x \cos x }dx$$ where $x \in \big(0,\frac{\pi}{2} \big)$  Could some give me hint as how to approach this question?  I tried to use the fact that $\sin ^4x+\cos ^4x=1-\frac{sin^22x}{2}$ but it didn't help. How should I proceed?


Does it mean we can never know the exact area of circle?

I performed three calculations for a circle of radius $10^7$ metre  $$(\pi-3.14)(10^7)^{2}=1.59265359\times10^{11}$$  $$(\pi-3.1415926535897)(10^{7})^2=9.31$$  $$(\pi-3.141592653589793238462)(10^{7})^2=0.00000006433832795028842$$ It implies large difference in the calculated area of the circle and it's dependence on the accuracy of value of $\pi$ used.  Since we may never know the actual value of $\pi$,Does it imply that it is impossible to calculate the exact value of the area of a circle?


Let $a$ and $b$ be relatively prime integers. Find all possible values of $\gcd(a+2b,a-2b)$

My attempt: it is known that $(a,b)=1$. Let $d = (a+2b,a-2b)$.  Then it follows that $d|{(a+2b)}$ and $d|{(a-2b)}$, and thus $d|{(m(a+2b)+n(a-2b))}$; that is, $d$ divides all linear combinations of $(a+2b)$ and $(a-2b)$.    If we write $X = a + 2b$ and $Y = a - 2b$, then:   $2X+2Y=4a$ and thus $d|4a$   $X-Y=4b$ and thus $d|4b$   Therefore $(4a,4b)=d$ and $(4a,4b)=4(a,b)=4$.  It follows that $(a+2b,a-2b) \leq 4$ and so 4,3,2, and 1 are possible values.  $(a+2b,a-2b) \neq 3$ given it is not a divisor of 4.  Therefore $(a+2b,a-2b) = \{4,2,1\}$  As one could imagine I'm posting because I am not sure of my proof. In particular I'm not certain whether the less than or equal to 4 actually follows from the previous line. As well as this, I'm not really certain my explanation for 3 not being in the answer set is adequate.


When we pass an Object[] to method, do we actually copy included objects or we just pass the array of references to those objects?


How do I make my nocturnal 4mo baby sleep at night?

My 4 month old son happily sleeps soundly for hours at a stretch during the day but when it comes to the night he won't go to sleep until 4 - 5am and when he does go down, he fidgets himself awake.   He suffered from really bad wind and reflux which kept him up until 5am and now his wind and reflux is getting better, his bed time just seems to be stuck at 5am.   We are trying to adjust his bed time by limiting his naps during the day (he currently has 3 naps daily between 1-2 hours), and putting him down at the earlier cycle (usually around 2am) but even when he goes to sleep, he's up after half an hour and then up until 5am. We are also waking him up around 11/12 but don't want to deprive him of sleep. We currently have a bedtime routine of bath, baby massage and feeding to sleep. We also control the light so it's bright and loud during the day and quiet and dark in the evenings.   Is there any advice on how to change a baby's sleep pattern without depriving them of sleep and avoiding controlled crying?


General relativity: For massless particles, is the momentum and velocity 4-vectors equal?

I am following Carroll's GR book. He explain that it is convention to parameterize geodesics of photons by a parameter $\lambda$ such that  $$p^\mu ~=~ \frac{d x^{\mu}}{d \lambda}.\tag{3.62}$$  But this is the definition of 4-velocity for a massive particle in the case of $\lambda=\tau$ equal to proper time. My question then, is $$u^\mu = p^\mu$$ for all massless particles? I ask because it's well-known that proper time $\tau$ freezes for massless particles.


In a USB cable, is it OK to swap the D+ and D- wires?

I heard that D+ and D- are differential signals, does it matter if I swap them when connecting a USB device to the computer?


How to move the polygons of an object into other location by bmesh frame by frame? I tried below way but failed. Is it possible to generate polygon movement animation effects like in Animation Nodes but by python? bpy.ops.mesh.primitive_monkey_add(size=2, location = (0,0,0)) obj = bpy.context.object obj.name='myobj' me = obj.data  ico0 = np.array([v.co for v in me.vertices]) # get ico vertices  #find out Zvalue zmin, zmax = ico0[:,2].min(), ico0[:,2].max() zc = np.linspace(zmin, zmax, n_frames) #print(zmin, zmax,zc) #return ico = np.zeros_like(ico0)


Let $f$ be analytic in a domain $D$ with $|f(z)| = k$, $k$ is real constant with $z \in D$. Prove that $f$ is constant.

Can somebody help me with this? Let $D$ be a domain. Suppose $f$ is analytic in $D$ and that for any $\displaystyle{z \in D, \left|f(z)\right| = k}$ for some constant real number $k$. Use the Open Mapping Theorem to show that $f$ is constant. I know that the Open Mapping Theorem says that if a function $f$ is analytic and non-constant in a plane domain D, then f is an open mapping of $D$.  In a particular, $f(D)$ is a domain. I don't know how to connect to show that $f$ is constant. I would appreciate for any help.  Thanks.


One of the cops escorts Tim out of the house and toward a police car. Curious neighbors have gathered outside. Tim spits on the cop escorting him. (1) - Tim spits on the cop who's escorting him. (2) - Tim spits on the escorting cop. (3)  Are the three suggested sentences all OK or are some of them awkward-sounding?


Shared library mappings in /proc/pid/maps

Why does /proc/pid/maps contain a few records for the same library ? Here is an example:  7fae7db9f000-7fae7dc8f000 r-xp 00000000 08:05 536861                     /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.20 7fae7dc8f000-7fae7de8f000 ---p 000f0000 08:05 536861                     /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.20 7fae7de8f000-7fae7de97000 r--p 000f0000 08:05 536861                     /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.20 7fae7de97000-7fae7de99000 rw-p 000f8000 08:05 536861                     /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.20   What does this mean ?


How did the house-elves become enslaved to wizards?

House-elves are magical creatures, that are bound to serve their wizard masters until death, unless they're given an article of clothing. How did they become enslaved? Did wizards create them? Are they enchanted? Did they willingly put themselves under this, since they actually ENJOY the slavery?  How did the house-elves become bound to their wizard masters?


Occasionally, the Unicode character sequence U+200C U+200B (ZWNJ ZWSP) is inserted into comments

In     ... the number "5000" does not paste as such but instead as  5 0 U+200C U+200B 0 0   The HTML source looks like this:  perhaps the easiest would be \edef\tmp{\everypar{\widowpenalty\the\widowpenalty\relax}}\tmp\widowpenalty=-50&zwnj;&#8203;00 that may reset   Or (smaller snippet):  \widowpenalty=-50&zwnj;&#8203;00 that   So in the HTML, we have extraneous &zwnj; and &#8203; in between the two middle digits of 5000.  Upon pasting and trying out this code, this first led to a mysterious compiler error. The same issue happened within a (now deleted) comment thread below ; there, these or similar two characters were inserted after the letter "r" within the string \ref ("\ref").  Note that not all browsers wrap the same way. The above screenshot was for Firefox 19.0.2, in which it breaks between \relax}} and \tmp, with 5000 insidiously left intact on the second line but with the two special characters remaining in the middle. So that is why this took me completely by surprise. Other browsers might indeed only break on the invisible Unicode characters, such as Chrome 25:    Or on a smaller screen with the mobile site, multiple line breaks might show, possibly still leaving the Unicode characters unused:


So When I logged into roblox I have put my age as ‘9’ and I am 14 years old. My username is poodles_246 and I would really like for roblox to try and change my age to 14 because it would really help out. Thanks


I was wondering if $AB=E$ ($E$ is identity) is enough to claim $A^{-1} = B$ or if we also need $BA=E$. All my textbooks define the inverse $B$ of $A$ such that $AB=BA=E$. But I can't see why $AB=E$ isn't enough. I can't come up with an example for which $AB = E$ holds but $BA\ne E$. I tried some stuff but I can only proof that $BA = (BA)^2$.  Edit: For $A,B \in \mathbb{R}^{n \times n}$ and $n \in \mathbb{N}$.


Show that $P[x]+\langle x\rangle $ is a prime ideal of $R[x]$.

Show that if $P$ is a prime ideal of a  commutative ring $R$ with unity then $P[x]+\langle x\rangle $ is a prime ideal of $R[x]$. Here $P[x]$ consists of all polynomials whose coefficients are in $P$.  I tried to show it using the fact that if $f(x)g(x)\in P[x]+\langle x\rangle $ then either $f(x)\in P[x]+\langle x\rangle $ or $g(x)\in P[x]+\langle x\rangle $. But I don't know how to show it. Please help me out.


I would like to keep track of changes in /etc/  Basically I'd like to know if a file was changed, by yum update or by a user and roll it back if I don't like the chage. I thought of using a VCS like git, LVM or btrfs snapshots or a backup program for this.   What would you recommend?


systemctl debian 8 jessie: Failed to get D-Bus connection: Unknown error -1

Unfortunately, in my Debian 8 jessie systemctl does not work at all.  Every systemctl command results in:  Failed to get D-Bus connection: Unknown error -1     systecmtl status udev           Failed to get D-Bus connection: Unknown error -1      How can I fix it?  I would be grateful for your help.


"Painful death is best gift" - from what short story?

In Soviet times there was one of selected best American sci-fi short stories printed here and there, and I believe it was one of those.  I always keep forgetting an author and title, cause the phrase "Painful death is best gift" is just imprinted in me.  So, an astronaut from Earth is settling on some remote planet with seemingly totally human-like aborigines (with a very early, a tribal peasants stage of their civilization). He has no problems in communications, he even falls in love and is happily married to some woman from a good family.  Having much more knowledge - medicine, construction, etc - he helps people a lot. And people seems very kind, open, maybe even naïve. Kind of pastoral happiness. They love and even to a degree worship him. He loves his wife and them too.  But weird things creep in. Like one wood cutter is died after a very thorny tree fallen over him, he was crying in pain for an hour before passing away. And our guy finds that the tree was covertly half-cut in wrong direction, and the cuts were somewhat masked, so allegedly the woodcutter would casually start axing it without noticing and gets killed. He suspects a murder but can't believe some one of those so open and kind people could be so double faced and can't think how he can investigate it.  Another villager falls into a mountain stream when the bridge falls. Our guy jumps into the water and manages to both pull him out and survive. The villagers are not happy though, they see this action as something very indecent. Like we would watch some savage killing neighbor and cooking him just to meet us from work with a feast. He wished well, but he did it in despicably harmful and wrong way. Like this.  Suddenly one of the villagers notes that the bridge ropes were semi-cut again, so and strong wind blow or jump could make them give way and make the bridge fall. The mood changes, now everyone again worships our guy and despises the saved local, like he was a fraudster. Our guy still thinks about finding a mysterious killer but no one else seems to take it seriously.  The suspense grows thicker an in the end we have his wife prepping herself for a night. She thinks how her husband is doing so many decent things, that he is so brave and kind, that he is almost saint. But of course he is so good, that he keeps himself reserved and he underestimates his good deeds, and he must not hurry and defraud the fate by setting his own death, like those deplorables did (he even risked his life to prevent that pathetic unworthy man to perish mischefly, that is why he was cheered). And that is how real saints should go. And she a good loving wife would help him: when his amount of good deals would mountain big enough and if the fate would still be too slow then she would reach for the family treasure - and she looks in a secret suitcase section upon a dagger covered with some ominous poison - cause the only best gift to the noble people you love can be, one that commits eternal happiness, is a torturous death.  Now, after this spoiler, I never can remember neither the author nor the title.


How to replace Cyanogenmod dialer/contacts/messaging(texting) apps?

I have a Samsung Galaxy S3 with Verizon. I've recently rooted it and installed Cyanogenmod 10.1.  Of ocurse, when you buy the phone brand new, it comes with all the built-in apps from the manufacturer. With the Samsung Galaxy S3, I prefer their original dialer/contacts/messaging apps vs. the ones that comes with Cyanogenmod.  Is there anyway to get back the original dialer/contacts/messaging apps and replace the ones on Cyanogenmod? Is there anyway to change custom ROMs to your liking? Is there a apk of the original dialer/contacts/messaging S3 apps?  I'm new to the world of custom ROMs and rooting Android, so please, if you could, be specific and detailed as, most likely, I won't know where your coming from.  Thanks!


How do I evaluate $\int_{1/3}^3 \frac{\arctan x}{x^2 - x + 1} \; dx$?

I need to calculate the following definite integral: $$\int_{1/3}^3 \frac{\arctan x}{x^2 - x + 1} \; dx.$$ The only thing that I've found is: $$\int_{1/3}^3 \frac{\arctan x}{x^2 - x + 1} \; dx = \int_{1/3}^3 \frac{\arctan \frac{1}{x}}{x^2 - x + 1} \; dx,$$ but it doesn't seem useful.


I've done a bit of reading about the twin paradox, as well as watched a few videos and the Wikipedia page on it, however, I don’t understand how their explanations explain away the problem. They claim that the acceleration solves the issue, however, don’t we arrive at the same problem? In the earth point of view the astronaut is accelerating, but you might as well see the earth as accelerating in the astronauts view. In other words, same problem, just with acceleration rather than velocity.


In XSD, SOAP and other XML conventions you'll often see things like:  <book>  <title>Harry Potter</title>  <author>J.K. Rowling</author> </book>   Now I'm wondering, what happened to attributes? To me it makes more sense to write this as:  <book title="Harry Potter" author="J.K. Rowling" />   But apparently, for some reason, smarter people than me chose otherwise. Could someone explain why, and what attributes are for then?


Question about proof of classifying groups of order $pq$

(Post has been edited )  So I am reading the proof of this statement:  Let G be a group of order $pq$ with $p,q$ primes and $p<q$.   If $p \nmid (q-1)$, then $G\simeq \mathbb{Z}_{pq}$  if $p \nmid (q-1)$ then thre are two isomorphism classes: $\mathbb{Z}_{pq}$ and a certain non-abelian group.  So, here is part of the proof (until the part that I have problems with):  Supposing that $p \mid (q-1)$, let $P \in Syl_p(G), Q \in Syl_q(G)$, since $\mid G:Q\mid = p$, which is th least prime number that divides $\mid G \mid$, then $Q \unlhd G$. Because $(\mid P \mid, \mid Q \mid)=1$, then $P \cap Q = \{e\}$, so $G=QP$.   Then $G$ is a semidirect product $Q \rtimes_{\theta} P$ for a certain morhpism $\theta : P \to Aut(Q)$.   Now they assert that $Aut(Q) \simeq \mathbb{Z}_{q-1}$.  Why is this? I am pretty sure this is not true for any group since complete groups are isomorphic to their automorphim group by definition.  Any help would be appreciated.


We consider following equation a×0=0 in this equation we able to multiply by zero.  but why not divided by zero? when multiplication and division are just inverse process.


Transferable Ubuntu between different machines

How can I create a USB system for Ubuntu on USB? I have several machines in the house to each of which I have occasional access; that is to say everybody has their own except me ... :( None of the other computer users in the house want me to partition their drives despite my protests that it will make no difference (except perhaps for GRUB) to their experience. This question is NOT about 'file transfer' nor about permanent 'account transfer'. I have tried unsuccessfully to edit an installation USB, but cannot make my account 'stick'. What I need is a 'roaming account' somewhat like an installation USB but without the clean start every time. UEFI is one problem - no 'legacy' choice in BIOS; a notebook without CD/DVD and with only 2 USB slots, is another. I have tried the PORTEUS solution, but as is usual with any initial installation of LINUX, I cannot access the internet - not even with my magic external wifi aerial, although it may be worth pursuing, because at the startup (as far as it goes) everything goes effortlessly. The galling thing is that the UBUNTU install usb-disk has internet connection without fail and is relatively uncomplicated to start - but with a clean slate every time! I have not yet tried the VPN solution - keep you posted. Please advise, thank you.


How do you change from icon to list view in 20.4

It must be there somewhere but it eludes me at the moment.


I wrote my , which I have uploaded (fortunately) in my pseudo-site. I had the source locally. There are some people that decided to work on my project, in order to make it better. As a result, they found typos. I aslo did find some. However, I lost the source of the thesis!  Can I do something about it, from having only the .pdf? Or should I ?


What justifies this calculation of the derivative of a matrix function?

In Andrew Ng's machine learning course, he uses this formula:  $\nabla_A tr(ABA^TC) = CAB + C^TAB^T$  and he does a quick proof which is shown below:  $\nabla_A tr(ABA^TC) \\ = \nabla_A tr(f(A)A^TC) \\ = \nabla_{\circ} tr(f(\circ)A^TC) + \nabla_{\circ}tr(f(A)\circ^T C)\\ =(A^TC)^Tf'(\circ) + (\nabla_{\circ^T}tr(f(A)\circ^T C)^T \\  = C^TAB^T + (\nabla_{\circ^T}tr(\circ^T)Cf(A))^T \\ =C^TAB^T + ((Cf(A))^T)^T \\ = C^TAB^T + CAB$  The proof seems very dense without any comments and I'm having trouble understanding it. What exactly happened from second to third equality?


Restoring Grub Launcher After Windows 10

I went ahead and installed windows 10 on my windows 8 and Ubuntu dual boot PC. All went smooth and Windows 10 works perfectly however the computer automatically boots to Windows and the grub launcher is missing. The partitions are still there I just need some help getting Ubuntu back. Thank you in advance!   Edit: I found a way around it. I don't know of this works for everyone but I went in to the control panel and went to update and recovery. Then I went to recovery and booted into uefi.  Then I selected boot from device and my Ubuntu partition was there and I could boot into it.  Feel free to post other solutions though!


Bluetooth for RTL8723DE is not working...!

Recently, I have purchased a new NoteBook of HP-BS145TU Series.  They only provide support for Windows.  I have two questions:   Is it fine to run Ubuntu on this machine? With some workaround, I could figure out, the way for Wi-Fi working, but couldn't proceed for the BlueTooth Functioning.   Please guide me properly.


I create a list<string> machineTypes and fill it with data. I want to check to see if the collection contains any combination of strings. My initial plan was to use a for loop, but obviously I can't check multiple indexes in the middle of a for loop.   for (int i = 0; i < machineTypes.Count; i++)             {                 if (machineTypes[i] == "W")                 //do stuff                 if ((machineTypes[i] == "P") && (machineTypes[i] == "W") && (machineTypes[i] == "A") && (machineTypes[i] == "C"))                     //do stuff             }   So I'm looking for suggestions as to the best way to do this. I suppose I could use String.Join, but I was wondering if there was a more elegant way.


How to get from CDG T1 to CDG T2D on a short layover

I am arriving at CDG T1 at 9 am on 30 Sept on Lufthansa and will be taking a flight from CDG T2D at 11 am the same day to Lisbon on Easyjet.    I am rather anxious whether I can make it in time to catch this connecting flight. Is two hours enough time to do this and how do I travel between these two terminals?


How should I track players' real-time positions in an MMO?

How do you keep track of the positions of the players in a MMORPG? I read that you can use either a database or you can store the coordinates in files. I tried using a database but it was slow. How can files be used to keep track of players positions?


I have added Elements using Jquery inside PHP after loading them from the database. Each button has two classes, one controlling the GUI and another controlling the Click for particular button. The code is as under       echo "<script type='text/javascript'>$('.main').append('<button class=b_ui b$index>Change</button>'); </script>";   Now if I check the classes from Inspect Element  perspective of the browser, it shows 2 classes. But when I click on it and get class of element using this code   $('.b_ui').click(function() {     cls = $(this).attr('class');     alert('no. '+cls); }   It shows only first class (GUI) and not the other which I want to use for handling click. Any help ?


How do I build a TRRS headphone jack with a jack that is detectable by an iPhone

I have a circuit and I am trying to integrate it with an iPhone via a TRRS headphone jack's microphone input. I have a generic TRRS cord and am trying to send a signal through it. However, the iPhone does not detect that a mic is even plugged in. However, if I plug it into my Mac via line-in and record, I can record the signal I am sending perfectly.   I have read online that it needs to detect resistance between the ground and mic, which I have. Are there any other things I need to do? It seems like this is an issue that stems from Apple's proprietary technology, as the earbuds are from a Windows Phone before they were spliced.    Thanks so much!


Show that a function $u$ has weak derivatives which satisfy the transport equation.

Let $v \in L^1_\text{loc}(\mathbb{R})$ weakly differentiable, $b\in \mathbb{R} \setminus \{0\} $ constant and $u:\mathbb{R}^2 \to \mathbb{R}$ defined by $u(x,t):= v(x-bt)$.  Show that $u$ has weak derivatives $ \partial_x u$ and $ \partial_t u$ which satisfy the transport equation $\partial_t u + b \partial_x u = 0$ almost everywhere.  I know the definition of the weak derivative, but since I don´t have any explicit function given I don´t know how to test it. I also wonder if there is a chain rule for weak derivatives, since $u$ is a concatenation of $v$ with $x-bt$.   Could anyone help me out with this problem? Thank you very much in advance!


Find the surface area of S which is is the part of $x^2 + y^2 + z^2 = a^2$ which lies in the cylinder $x^2 + y^2 = ay$

How do I set up the integral to find the surface area if I only have the two shapes a sphere and a cylinder ?


Passing variable as column name in a select query

I've got a variable set at the top of my PHP:  $abc = "paid";   Now I need to pass it on to the below query as a column name. I tried the below but it did not work.  $sql = "SELECT customerID FROM payments WHERE :myVar = :credit"; $stmt = $connect->prepare($sql); $stmt->execute(array(':credit'=>"0", ':myVar'=>$abc));   How do I pass $abc on to the select query as a column name?


Solution for $\sum_{i=0}^{n} \sin(\frac{i\pi}{2n})$?

While I was trying to find the formula of something by my own means I came across this sum which I need to solve, however I don't know if there is a solution for it, maybe it doesn't mean anything and I made a mistake. However if there's an equation which can replace this sum I will appreciate it a lot if you show me which one and how did you find the answer!


Normal distribution probability calculation

I am stuck with a stats question..... help please     A television manufacturer is studying television remote control usage. One of the criteria they are measuring is the distance at which people attempt to activate the television set with the remote control. They have discovered that the activation distances are normally distributed with a mean distance of 6 feet and a standard deviation of 2.75 feet. If a remote’s maximum range is 10 feet, what percentage of the time will users attempts to operate the remote outside of its operating limit?


Points get transformed into underscores php $_GET?

So the other day i was debuging some code and the $_GET parameter names were send with dots like for example those:  ?user.name=test&user.age=20   When i wanted to use them i saw they were renamed with underscores like so  $_GET['user_name'] $_GET['user_age']   So my question is, why is this happening?


How to delete History of installed packages

I need to delete the Synaptic/Software Center history(commit logs). How can I go about doing this?


Given that time slows to a stand-still at the event horizon of a Black Hole, how long would it take a black hole to form, from the perspective of an outside observer?  It would seem, as a massive star collapses into a Black Hole, time on the surface of the star would slow as the gravity on the surface reaches the level of a black hole.  Within the collapsing star, gravity is less and time continues closer to normal speed.  Looking at it from the outside, far away, the black hole never quite forms.  As it would take an infinite amount of time.  Any thoughts on this?


Alien fails on rpm, Install Maya 2017 on Ubuntu 16.04 LTS

I'm trying to install Maya 2017 on Ubuntu 16.04 LTS. So far, everything looks good until it comes to the alien command to get .deb out of the .rpm.  root@Borderline-Central:~/maya2017Install# alien -c *.rpm sh: 1: rpm: not found Error executing "LANG=C rpm -qp --queryformat %{NAME}'adlmapps12-12.0.32-0.x86_64.rpm'":  at /usr/share/perl5/Alien/Package.pm line 489.  root@Borderline-Central:~# apt install rpm Reading package lists... Done Building dependency tree   Reading state information... Done rpm is already the newest version (4.12.0.1+dfsg1-3build3). 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.  root@Borderline-Central:~# rpm The program 'rpm' is currently not installed. You can install it by typing: apt install rpm   If I try  for i in *.rpm; do sudo alien -cv $i; done   Same problem with rpm not found.    I've tried to purge rpm, installed it again. It doesn't help at all    I've started with Ubuntu a month ago so I'm new and I think I'm missing something.    rpm is installed but can't be found somehow.    What's the problem and how can I fix it?    It's not a duplicate question, I've done the installation similar to the description in the link to GitHub. But my problem is that rpm isn't found even if it's said rpm is already the newest version. So still the question. How can I fix the missing rpm problem!?    As requested the output of which rpm and ls -l /usr/bin/rpm   hethu@Borderline-Central:~$ which rpm   /usr/bin/rpm    hethu@Borderline-Central:~$ ls -l /usr/bin/rpm   -rwxr-xr-x 1 root root 15208 Jan 19  2016 /usr/bin/rpm


Work for US Healthcare company from India - Tax forms

I have question regarding work arrangement for remote work from India for US company.   My scenario. I am currently employed on H1B with a Healthcare organization based out of Indiana, US. My work visa expires in June 2018 following which I will move back to India. My employer is wanting to secure my project consulting services as independent contractor. I am setting up a retainer agreement with monthly payment paid directly to my savings account. Given all this,    I am not forming a LLC or corporation. I will be the sole proprietor and no other legality. Any issues with that approach?  Other form aside from W8BEN do I need to submit to my HR such as W9? I know I need to submit W8BEN so they don't withhold any federal/state/local taxes and such, but what about Medicare and Social security taxes? What forms are required to stop withholding from that aspect or am I liable to pay those? Will I get 1099 from them towards end of year? For employers convenience, I would leave my US bank account running and request payments routed to it just as it does today and transfer to Indian bank account? Or should I apply for NRE/NRO? Which is the best option and any legal issues?   Any guidance will be much appreciated. Thank you in advance!


Find best unbiased estimator for $\theta$ when $X_i\sim U(-\theta,\theta)$

I am having an issue finding a best unbiased estimator for $\theta$. Any help is appreciated. Let $X_1, ..., X_n$ be a random sample from a population with pdf: $f(x\mid\theta)=\frac{1}{2\theta}$ $-\theta<x<\theta,\, \theta>0$. I understand that $T(x) := |X_n|$ is the sufficient statistic since by the factorization theorem we have: $$f(x\mid \theta) = \left(\frac{1}{2\theta}\right)^n \prod_{i=1}^n I[|x_i|<\theta]$$ I think my main issue is showing that this sufficient statistic is also a complete sufficient statistic. Can somebody please aid me in this?


What settings to use for portrait with white background?

I am newbie trying to get a good picture of my friends (contrasting skin color) with snow covered mountain in the background. I tried using aperture priority mode with f/11 and 1/100 sec, 28 mm. People in the picture looked okay, but the background appeared too whitish or the background looked okay but people turned out too dark. After that I came across metering modes online, and I'm wondering which one I should use (spot metering appeared correct). Shot is taken 8 steps away from the people with Canon 60D. What all things should I consider to get a decent picture in this scenario?  What mode? TC/AV/Manual. What metering mode? What settings?


By default, \in produces a lunate epsilon that is just a crazy, ridiculous size.  What is the most correct way to make it smaller?


include variable in another variable in bash

I am writing a loop in bash where I want to include one variable in another variable:    printf "Number of volumes to add: "   read -r num_volumes   for volume_number in "$num_volumes"   do     vol_id_{$volume_number}="create_volume"   done   Is this the correct syntax to use?


Make specific author bold using biblatex

I am writing my CV in LaTeX. I am using biblatex and want my name (and only my name) to be bold for every reference. Is there a magic way to do this?  A similar question  was asked, but that answer used BibTeX. While I use the BibTeX backend, I use biblatex.  Any suggestions?


Creating a list of lists by multiplying a list unexpectedly leaves inner lists connected

Let's say I want to create a list of lists to be filled later, that looks like that:  [['', ''], ['', ''], ['', '']]   I can create it like so:  rows=3 cols=2  A=['']*cols B=[A[:]]*rows   However, the inner lists are the same object, as can be seen:  B[0][0]='!' print (B)   Output:  [['!', ''], ['!', ''], ['!', '']]   This occurs even though I used B=[A[:]]*rows rather than B=[A]*rows; using  B=[A][:]*rows does not solve the problem.  If A[:] should efficiently create a full copy (rather than just a reference) by slicing A, then why does this occur?    P.S.  Obviously this can be easily solved for example by:  this_text=[] temp=[] for i in range(cols):     A.append('') for i in range(rows):     B.append(A[:])   My aim is improved understanding, not creating this specific list of lists.


How to match carriage return in java regular expression

This is the regular expression I use, but it doesn't match string "%test\n###Hello". Could anyone help what's wrong in my regular expression ? Thanks  private static Pattern REPL_PATTERN = Pattern.compile("%([\\w\\.]+).*");


Does publishing a paper in a fake journal get someone in trouble?

I am a young graduate student in Egypt. I have published few papers in high ranking journals in my field. One of the professors in my department is constantly publishing papers in these fake journal that accept a paper in a couple of days in exchange of money. He practically publishes a new paper every week. Universities here don't know much about fake journals and they recognise any paper as long as its published in journal with impact factor without knowing that some of these journals have fake impact factors. Also, his papers basically talk about the same thing and he keeps changing the title and spinning the content. Anyway this guy is constantly getting honoured for his research even though he has never published a paper in an honourable journal and he has just been made the head of the department I am in. I am not bitter but I just think its not fair and I don't know what to do about it. I am afraid if I say something he may cause a problem for me.


I wrote an article in LaTeX using document class article and the natbib package, together with apacite. However, the publisher has so many requirements which are indiosyncratic that I think the easiest solution is just to write out the bibliography by hand and then remove the LaTeX produced bibliography pages using a PDF editor. I know this sounds quirky but I'm not sophisticated enough to keep modifying the apacite package. So, I copied and pasted it from the original REFERENCES list and then pasted it as plain text. Perfect, right? Nope. The trouble is, the second line of the text doesn't indent automatically and the first one does. In other words, I want to manually obtain outputs like this:  Is there a technique or tool to help me achieve this formatting, but without messing up my perfectly organized text-internal citations?


How do I access a static map from a seperate class in C++?

I'd like to access a static map that is stored in a seperate class and iterate through and print the contents.    So I have three files:  HasGlobals.cpp which has the global map.  /* HasGlobals.cpp */  #include <string> #include <map> #include <iostream>  class HasGlobals{     public:         static std::map<int, std::string> globalData;          HasGlobals(){             globalData.insert(std::pair<int, std::string>(0, "data"));         };          ~HasGlobals(){         }; };   WantsGlobals.cpp which has a method that needs to use the map from HasGlobals.cpp for one of its methods.  /* WantsGlobals.cpp */  #include "HasGlobals.cpp" #include <string>  class WantsGlobals{     public:         WantsGlobals(){         };          ~WantsGlobals(){         };          //THIS IS THE METHOD THAT I CAN'T GET TO WORK         void printContentsOfGlobal(){             HasGlobals * globalRetriever = new HasGlobals();             for(std::map<int, std::string>::iterator it = globalRetriever->globalData.begin(); it != globalRetriever->globalData.end(); ++it){                 std::cout << it->first << " " << it->second << std::endl;             }         };     };   Main.cpp which simply tries to call the printContentsOfGlobal() method in WantsGlobals.cpp.  /* Main.cpp */  #include <iostream> #include "WantsGlobals.cpp"  int main(){     WantsGlobals * globalRetriever = new WantsGlobals();     globalRetriever->printContentsOfGlobal(); }   Right now this code doesn't compile and gives me     undefined reference to 'HasGlobals::globalData'   How would I implement printContentsOfGlobal() so that I can retrieve the data in the map[globalData] in the seperate HasGlobals.cpp file?  EDIT: Thanks for the help everyone.  Below is the code I created with everyone's help.  Yes it's still not perfect but it compiles and performs the desired behavior:  HasGlobals.hpp  #include <string> #include <map> #include <iostream>  class HasGlobals{     public:         static std::map<int, std::string> globalData;          HasGlobals(){};          ~HasGlobals(){};          static std::map<int, std::string> createDummyData(){             std::map<int, std::string> m;             m[0] = "Help";             m[1] = "Me";             m[2] = "Stackoverflow";             m[3] = "You're my only hope.";             return m;          } };  std::map<int, std::string> HasGlobals::globalData = HasGlobals::createDummyData();   WantsGlobals.hpp  #include "HasGlobals.hpp" #include <string> #include <map>  class WantsGlobals{     public:         WantsGlobals(){};          ~WantsGlobals(){};          void printContentsOfGlobal(){             for(std::map<int, std::string>::iterator it = HasGlobals::globalData.begin(); it != HasGlobals::globalData.end(); ++it){                  std::cout << it->first << " " << it->second << std::endl;              }          }; };   Main.cpp  #include <iostream> #include <"WantsGlobals.hpp">  int main(){     WantsGlobals * globalRetriever = new WantsGlobals();     globalRetriever->printContentsOfGlobal(); }


I need the source code to build a ubuntu phone rom for the moto x

If i could get the source code for ubuntu phone os, i could compile a build of the os for the moto x, which a good number of people want.


Make macros with random (but specific) output

I try to find a way to make a  \newcommand   so that it has different outputs, that it chooses randomly. In the best case the macro should also avoid word repetitions (something like, only choose this word if it hasnt been used for 50 words).  In this macro I want to group similar words, I use a lot in the document. For example if I often write the same name, it should sometimes just print the family name and other times the full name.  Edit another example: the macro should print "the group" or "the group of people" or any different synonym, so that I just have one macro for this pool of words.


Compatibility of the .bbl output of biber versus bibtex

What is the difference between the  .bbl  file produced by Biber versus Bibtex?   The problem is that arXiv.org doesn't work with the  .bbl  file produced by Biber but it does work with the Bibtex output. Is there any way around this issue?


How to use the 3-D scale/rotate tool to create depth in Illustrator?

I've a very simple rectangular shape that has been filled with a hexagon texture. I'm looking to create a sense of depth by keeping the lowermost row of the hexagons largest while transforming the top row to be smaller so they are appear to be in the distance.  This would be similar to creating a chessboard like 3-D feel. Any recommendations or proper ways to use the tool without relocating the actual placement of the rectangle – just be inner dimensions?


Dave has 10 poker chips, 6 of which are red and the other 4 of which are white. Dave likes to stack his chips and flip them over as he plays. How many different 10-chip stacks can Dave make if two stacks are not consider distinct if one can be flipped to appear identical to the other?


below code is weird. when i debug it, i can see both "result" and "round" are 5, but output is "false". Any idea?  double result = Math.Log (243, 3);   // 5 double round = Math.Round (result);  // 5 Console.WriteLine (result == round);


If I remove my SIM card from my iPhone, will iMessage still be connected to my phone number, or can I only be reached by my Apple ID email?

I'm traveling internationally and I'm removing my SIM card. Even if I don't have my phone number connected to my iPhone by the SIM card, will it still be connected to iMessage for people to contact me through? Should I tell them to text my Apple ID email(s)? Or well I still be able to receive the messages if they text my phone number?


Looking for title/author of a short story about sailors dying of thirst who enter another world

I am looking for one particular short story that was in an anthology of sci-fi from the 1960s or 1970s. The title of the story may have been "The Village Green" or something like that.  In it, a group of desperate, dying sailors slip out of the earth into some other dimension/reality: an unformed world where at first there is only a stream and some breadfruit trees, but slowly their collective imagination fleshes out the world.  I think that only their distance from other people allowed them to slip away.    Another thing I remember is that one of the men, named Kruger, doesn't quite make it all the way and remains a disembodied spirit of sorts in the new world, plagued by thirst.  Eventually the protagonist makes his way back to Earth, where he is still thirsty.  Does anyone remember this story?   I want to read it again but can't remember the author or exact title...


Can a uniform circular motion be considered as simple harmonic motion?

The acceleration in a circular motion is directed towards the centre and is directly proportional to the radius of circle if it has uniform angular velocity. Is circular motion with uniform angular velocity simple harmonic motion?


How much cash can I carry when travelling to the US?

I was wondering if someone knows the legal limit of cash money allowed per adult tourist when entering the US, especially from the UK.  The reason is that I would like to get the best conversion rate and buy some dollars (selling my GBP) at the UK cambios/exchange offices so that my bank fees and other charges can be avoided. Therefore, taking the legal limit of cash will help me to make the most out from the currency conversion mishapps.  Any idea on those numbers?


Why is the voltage across a capacitor and the current across an inductor continuous?

Why is the voltage across a capacitor (as a function of time) continuous? Why is the current across an inductor (as a function of time) continuous?


Jargon for when your site's bandwidth quota is eaten up by traffic from a backlink in a popular blog?

This happens every now and then on the web. Charlie has a personal blog where they posts about technical stuff. One day a popular site finds about their posts, and decides to do an article on it, linking to the source, of course.  The incoming traffic eats up Charlie's provider's bandwidth quota, and is taken down by the provider.  Is there a term for this unavailability of a site due to unexpected traffic from suddenly being famous?


bash iterate file list, except when empty

I thought this would be simple - but it is proving more complex than I expected.  I want to iterate through all the files of a particular type in a directory, so I write this:  #!/bin/bash  for fname in *.zip ; do    echo current file is ${fname} done   This works as long as there is at least one matching file in the directory. However if there are no matching files, I get this:  current file is *.zip   I then tried:  #!/bin/bash  FILES=`ls *.zip` for fname in "${FILES}" ; do     echo current file is ${fname} done   While the body of the loop does not execute when there are no files, I get an error from ls:  ls: *.zip: No such file or directory   How do I write a loop which cleanly handles no matching files?


Parsing multivalue parameter using ArcPy?

I am trying to get my head around how multivalues derived from the arcpy command GetParameterAsText gets looped through a script. Could some please provide a sample script that does the follow basic task so that I may study it for further insight?  Get a set of shapefiles from arcpy.GetParameterAsText(0) (the number of shapefiles can vary from to 10 say) and then loop through each shapefile, displaying the following with arcpy.AddMessage saying something to the effect:     "This is shapefile " shapefile name   When looped through all of the shapefiles, print the message "No more shapefiles"


If I purchased Minecraft for PS3, can I play on PC?

I have purchased Minecraft for PS3, however for various reasons I am dissatisfied with the PS3 experience and I would like to continue playing on PC.  Does the PS3 purchase/license allow me full access to the PC version and/or any other versions of Minecraft?


How can I keep a cheesecake from cracking?

I've been making cheesecakes for a while and they always end up cracking on the top.  I was told to try putting a pan of water in the oven with it to keep the humidity up, which might help a little, but then it tends to crack when it's cooling.  Am I overcooking?  Or baking at the wrong temperature?  Whipped cream can only cover up so much.


I am having the transaction dataset which contains 95% or user initiated transactions and 5% fraud transactions. When I am fitting the logistic regression model, it gives me bias prediction - as most of the transactions are as user initiated. So, I want to fix this issue of data distribution or other issue?  One of source suggested that prior probability can help in this issue. If this is true can any one explain? What's it and if this is not helpful then which are the possible solution for this problem?  I have other user profile variables but I want to get this thing solved without considering them. Is there any solution ?


C Shell Array Declaration Syntax, () vs. {}

In my C-shell script (tcsh specifically) I have been trying to declare an array with six values: x, nx, y, ny, z, nz. After some trial and error I discovered three different ways of declaring the array I want:  set arrname = ("x" "nx" "y" "ny" "z" "nz") set arrname = (x,nx,y,ny,z,nz) set arrname = {x,nx,y,ny,z,nz}   but the following line doesn't work:  set arrname = {"x" "nx" "y" "ny" "z" "nz"}   The above line produces the following error:  Missing }.   My question is what is different between () and {} that makes the fourth declaration I've listed not work?


Why don't two pieces of matter stick together?

If I have two perfectly smooth planar surfaces of two solid objects made of the same element and make them touch, why do they not stick and form a single bigger object? By 'touch' I mean bring the pieces so close together that the two most outer layers of atoms of the two object are as close as the second most outer layers of each object to its most outer layer. How do the atoms know to which object they belong? Is it imperfection and dirt or is my intuition wrong?


I am following the ebook Big Java Late Objects - and I have problem resolving on of the tasks. It is about inheritance. There is Question class and one sub ChoiceQuestion class that extends it.  But when I run the code in my testclass it calls the null exception and I don't know why.  Exception in thread "main" java.lang.NullPointerException at ChoiceQuestion.addChoice(ChoiceQuestion.java:12) at TestClass.main(TestClass.java:21) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at                  sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)   Here are my classes:  public class Question { private String text; private String answer;  /**  *  Constructs a queston with empty question and answer.  */ public Question(){     text = "";     answer = ""; } //=============Setter methods============ public void setText(String questionText){     text = questionText; }  public void setAnswer(String correctResponse){     answer = correctResponse; } //==============Getter Methods============= public boolean checkAnswer(String response){     return answer.equals(response); } public void display(){     System.out.println(text); } }   And here is my subclass:  class ChoiceQuestion extends Question { private ArrayList<String> choices;   //=========Methods============== public void addChoice(String choice,boolean correct){     choices.add(choice);     if(correct){         //convert choices.size() to string         String choiceString = "" + choices.size();        this.setAnswer(choiceString);     } }  public void display(){     // Display the question text     super.display();     // Display the answer choices     for(int i=0;i<choices.size();i++){         int choiceNumber = i + 1;         System.out.println(choiceNumber + ": " + choices.get(i));     } } }   And my test Class:  import java.util.Scanner;  public class TestClass { public static void presentQuestion(Question q){     q.display();     System.out.println("Your answer: ");     Scanner in = new Scanner(System.in);     String response = in.nextLine();     System.out.println(q.checkAnswer(response)); } public static void main(String[] args) {     Question first = new Question();     first.setText("James Gosling");     first.setAnswer("James Gosling");      ChoiceQuestion second = new ChoiceQuestion();     second.setText("In which country was the inventor of Java born? ");     second.addChoice("Austria", false);     second.addChoice("Canada",true);     second.addChoice("Denmark",false);     second.addChoice("United States",false);      presentQuestion(first);     presentQuestion(second);  } }


Is the hamburger icon a recognized navigation symbol?

Do you think the icon "☰" is enough for users to know that a menu is underneath?  Medium.com doesn't even use an icon, it is linked from its logo on the top.  Other websites just use the word "Menu" which I think is a little more intuitive.  Is the "☰" becoming the international symbol for "menu/navigation"?


Why does the beamer foreground color change colors of an included PDF file?

I have vector graphic created with Adobe Illustrator CS4 saved as PDF, it looks like:    You can download the PDF .  As you can see, the lines are black.    If I include the PDF with \includegraphics in a beamer document which has a changed foreground color, all lines of my graphic get colored in that color!  \documentclass{beamer} \usepackage{graphicx} \setbeamercolor{normal text}{bg=white,fg=red} \begin{document} \begin{frame} \includegraphics[width=0.5\textwidth]{dummy.pdf} \end{frame} \end{document}     Oh yes, that's unexpected.   What goes wrong? Is that really intended behaviour?  How do I get my lines black again?  If it's a problem related to the graphicx package, I'd prefer a solution by that package. But a beamer workaround would be fine as well. I tried to locally set  \setbeamercolor{normal text}{bg=white,fg=black}   but it does not have any effect. Also I need the foreground color as it is (non-black), just the graphic should be affected by the change.


Tar a list of files without their directory structure

Say I do this:  tar cvf allfiles.tar $(<mylist.txt)  and mylist.txt contains this:  /tmp/lib1 /tmp/path2/lib2 /path3/lib3   How to tar the files so the tarball contains just  lib1 lib2 lib3   with no directory structure at all?    The -C of --directory options are usually recommended (, ), but there are multiple directories so this doesn't work. Also, --xform looks like it requires a fixed pattern () which we do not have.


Distance in relativistic circular motion in invariant spacetime

I understand that the closer something travels to the speed of light, that time will stretch by a factor, and distance will compress by the same factor.  My question is, if something travels in a circle, close to the speed of light, what does the distance of the journey look like to them? They measure that the trip took them 10 minutes. And an outside observer says that the journey took 20 minutes, and the outside observer measured that they did, for example, 1000 laps of a circle circumference 1000 km.  So if the plane had a distance trip counter, what would it read? And if they were looking out of the window, would the circle still look like it had a circumference of 1000km?


I have to prove a few different statements.   The first is if $A \subset B$ and $B \subset C$ then prove $A \subset C$. This one is fairly straight forward, but I'm stuck on how the next one differs.   Prove that if $A \in B$ and $B \in C$ then $A \in C$.   I don't really understand how to put this in logical symbols. I've only seen $a \in A$ written out but never "a set $A$ is an element of a set $B$".  Here's what I have for a proof at this point, assuming I understand what "a set $A$ is an element of a set $B$" means: suppose $A \in B$ and $B \in C$.  Then $A \in C$.


I would like to be able to selectively edit specific auto-fill form values in Safari - rather than just delete the entire form data for that site.  I know I can do the latter from Prefs > AutoFill > other forms > Edit… but I'd rather be able to remove only the the oddities my errant typing appears to have generated, rather than the actually useful auto-fills I already have in there.  As an example, from the Edit panel in Ask Different itself, I appear to have several aborted versions of "Formatting". I would rather have just the 'correct' entries.     A guess would be that the data resides in ~/Library/Safari/Form Values but that file seems to be either encrypted or perhaps binary - I can't tell which.  OS X 10.10.4 Safari 8.0.7


What's the difference in meaning between "emigrate" and "immigrate"?

What's the difference between emigrate and immigrate? They seem to have the same definitions in the dictionary but they are antonyms...


Elevated Priviliges for Startup Applications in Windows?

Is there any way to configure application that requires administrator privilages (elevation) so it's automatically started with elevated privileges and does not request elevation on every startup?  For example, I have Riva Tuner that always starts with Windows. And it always asks for elevation via UAC. I need Riva Tuner to silently start with elevated privileges and without any message from user account control (without disabling it).


How to Create a Full Install of Ubuntu 20.04 to USB Device Step by Step

Every issue of Ubuntu LTS since 8.04, I have made a Full install of Ubuntu to USB flash drive, and recorded each step..  This has been intended to make a guide/check list for users wishing to create Full install bootable flash drives.  Previously the procedure worked for BIOS boot if created in BIOS and for UEFI boot if created in UEFI.  This year for 20.04 the instructions should work for both creating and running the drive booted from either BIOS or UEFI.  The question is:  How to Create a Full Install of Ubuntu to USB device with Step by Step instructions that work in either BIOS or UEFI.


Election notification description is not displaying in the global inbox

Recently I received a notification about the Travel SE election nomination, I can read the notification description in the Recent inbox messages.        But the same notification description is not displaying in the global inbox page.        This display issue is not specific to Travel SE, I found the same issue for other Stack Exchange communities.  Screenshot reference for the Stack Overflow election's three phases notifications.


Whitespace when using itemize after a full line, how to get rid of it?

Recently I've tried to create a very simple custom itemize-environment, I call it bla for now, and it works just fine almost always. I've defined it as follows:  \newenvironment{bla}    {\vspace{-.2cm}    \begin{itemize}       \itemsep-.05cm    }    {    \end{itemize}    \vspace{-.3cm}    }   There is only one problem; when I use this environment immediately after a full line, a blank line is inserted before the list starts. For example, the following code  \documentclass[twoside,12pt,a4paper]{report} \usepackage[top=3cm, bottom=3cm, outer=1.5cm, inner=2.5cm]{geometry} \newenvironment{bla}    {\vspace{-.2cm}    \begin{itemize}    \itemsep-.05cm    }    {    \end{itemize}    \vspace{-.3cm}    }  \begin{document} \noindent When I use this environment after a full line I get a blank line first, as this very example shows: \begin{bla} \item See the whitespace? \end{bla} \end{document}   gives the following output:    Note the absurd amount of white space. If the line before the bla-environment is not full, this issue doesn't occur. The code  \noindent Whereas there is no blank line if this line isn't full, as this example shows: \begin{bla}    \item    See the whitespace? Exactly. \end{bla}   with the rest of the code the same as before, gives the desired output:    Question: How do I get rid of this blank line that's inserted when the line is full?  Note that the issue also doesn't occur in the regular itemize-environment, as the code  \noindent When I use this environment after a full line I get a blank line first, as this very example shows: \begin{itemize}    \item    See the whitespace? \end{itemize}   gives far less white space than the bla-environment. It gives the output    But I would expect there to be less in the bla-environment, due to the \vspace{-.2cm} there. I'm curious to know why there is more white space.    Update: I added % into the code as suggested, but I get the same ouput with  \documentclass[twoside,12pt,a4paper]{report} \usepackage[top=3cm, bottom=3cm, outer=1.5cm, inner=2.5cm]{geometry} \newenvironment{bla}    {%    \vspace{-.2cm}%    \begin{itemize}    \itemsep-.05cm       }    {%    \end{itemize}%    \vspace{-.3cm}%t    } \begin{document} \noindent When I use this environment after a full line I get a blank line first, as this very example shows: \begin{bla}    \item    See the whitespace? \end{bla} \end{document}


I'm reading Stopple's A Primer of Analytic Number Theory:     Exercise 1.1.3: Which triangular numbers are also squares? That is, what conditions on $m$ and $n$ will guarantee that $t_n=s_m$? Show that if this happens, then we have:      $$(2n+1)^2-8m^2=1,$$      a solution to Pell's equation, which we will study in more detail in Chapter $11$.   I thought about the following:  $$\begin{eqnarray*}   {t_n}&=&{s_n} \\    {\frac{n^2+n}{2}}&=&{m^2} \\    {n^2+n}&=&{m^2}  \end{eqnarray*}$$  I've solved for $n$ and $m$ but I still have no clue of how to proceed. I've looked at the book's solution and the solution is as follows:   $$\begin{eqnarray*}   {\frac{n(n+1)}{2}}&=&{m^2} \\    {n(n+1)}&=&{2m^2} \\    {\color{red}{4n(n+1)}}&\color{red}{=}&{\color{red}{8m^2}} \\   {4n^2+4n+1-1}&=&{8m^2} \\   {(2n+1)^2-1}&=&{8m^2} \\ \end{eqnarray*}$$  In the red line, he multiplies the equation by $4$, I don't understand why to do it nor how the condition is achieved.


Trying to identify a book about life on the side of an infinitely tall wall

I'm trying to find a book about a city built on the side of an infinite wall - infinitely tall as well as infinitely long. There was a picture of it on the cover. The city is built on platforms jutting out, and if you fell off, you'd be gone forever. Unfortunately, I can't remember the title, the author, the publisher or anything else but the setting, but I think the plot might have been a detective story.


Itachi at the beginning of the fight with Sasuke says that he wants Sasuke's eyes to be his new light, meaning that he wants the Eternal Mangekyo by transplanting Sasuke's eyes. But Sasuke did not have the Mangekyo at the time - doesn't he have to transplant Mangekyo eyes to obtain eternal Mangekyo or does replacing Mangekyo eyes with regular Sharingan eyes do the trick as well?


How to use a custom property of an object as input for a driver?

I would like to be able to control the power/energy of multiple lamps using a driver. My idea is to have an empty that I would move on the Z axis between 0 and 1 to multiply the energy of each lamp. On the lamp power attribute, I have  and this driver expression: self.energy * var   Edit It seems to provoke a kind of expression loop, and the value is increasing exponentially. So I guess my original "power" value should be defined elsewhere, maybe as a custom property of my lamp object ?  How could I link one to my driver expression?


I'm trying to securely keep a user logged in using php but am worried about security.  So I've been going by this . But There's still a few things I don't quite understand.  Please keep in mind I'm not an expert by any means, so please speak as if you were talking to a child.  function onLogin($db, $user) {   $token = GenerateRandomToken($db); // generate a token, should be 128 - 256 bit   storeTokenForUser($db, $user, $token);   $cookie = $user . ':' . $token;   $mac = hash_hmac('sha256', $cookie, 'SECRET_KEY');   $cookie .= ':' . $mac;   setcookie('rememberme', $cookie, time() + (86400 * 7)); }   My question is, how is this secure? I will be storing it in a cookie, which under my knowledge is viewable by users. The "SECRET_KEY" in hash_hmac must have something to do with it but I didn't find much information on how to use it in the manual.  Will the "SECRET_KEY" in hash_hmac be the way that I can secure my cookies? If so, how do I use it? Will it be the same everytime? or should I generate a random ID for it?  Thanks for your time. Greatly appreciated.


Let f:G to H be 1-1 homomorphism show that order of f(a) divides the order of G.

Let $f:G \to H$ be an injective homomorphism. Show that order of $f(a) \in H$ divides the order of G.  Let the order of $|G|=n$. I'm not sure where to go from here. I've seen examples showing it divides an element $g$ but not $G$.


How to add variable to PATH system variable?

I am trying to add to my Windows 10 a new folder to my existing PATH system variable. But I'd like to add it as a nested variable.  So what I did was:    Create a variable for my folder as a system varaible:  bla=c:\dev Added the folder I created as a param to my existing path:  PATH={current path};%bla%   But, after restarting,  when trying to use it the path didn't recognize the new variable. When I tried to view the PATH from command line I saw the varaible unrecognized. meaning when I typed: c:>set path  I got: {path};%bla%  What should I do in order to use variable as part of my path. Should it be located in another place and not a a system varaible?


I want to use a big product symbol I have a problem

\documentclass[14pt]{memoir} \usepackage{lmodern} \usepackage{amsfonts} \usepackage{amstext} \usepackage{amsmath} \usepackage{amsmath} \usepackage{mathrsfs} \usepackage{amsthm} \usepackage{mathtools}  \begin{document} $$P:=\prod_{\sigma\in \textnormal{Gal}(L/K)}\big(X-\sigma(b)\big)\in A[X],$$ \end{document}


Finding $\int \frac {dx}{\sqrt {x^2 + 16}}$

I can not get the correct answer.   $$\int \frac {dx}{\sqrt {x^2 + 16}}$$  $x = 4 \tan \theta$, $dx = 4\sec^2 \theta$  $$\int \frac {dx}{\sqrt {16 \sec^2 \theta}}$$  $$\int \frac {4 \sec^ 2 \theta}{\sqrt {16 \sec^2 \theta}}$$  $$\int \frac {4 \sec^ 2 \theta}{4 \sec \theta}$$  $$\int \sec \theta$$  $$\ln| \sec \theta + \tan \theta|$$  Then I solve for $\theta$:  $x = 4 \tan \theta$  $x/4 = \tan \theta$  $\arctan (\frac{x}{4}) = \theta$  $$\ln| \sec (\arctan (\tfrac{x}{4})) + \tan (\arctan (\tfrac{x}{4}))|$$  $$\ln| \sec (\arctan (\tfrac{x}{4})) + \tfrac{x}{4}))| + c$$  This is wrong and I do not know why.


When are minimal and characteristic polynomials the same?

Assume that we are working over a complex space $W$ of dimension $n$. When would an operator on this space have the same characteristic and minimal polynomial?    I think the easy case is when the operator has $n$ distinct eigenvalues, but what about if it is diagonalizable? Is that sufficient, or can there be cases (with repeated eigvals) when char poly doesn't equal min poly? What are the general conditions when the equality holds? Is it possible to define them without use of determinant? (I am working by Axler and he doesn't like it.)  Thanks.


I am using Ubuntu 16.04. I have posted a screenshot of my partitions below. My root partition /dev/sda1 is almost full, and my /home partition /dev/sda3 has plenty of unused space. Is there a way that I can use some space from /dev/sda3 to increase the size of my root partition /dev/sda1 ?


Login SSH with .ppk file on Ubuntu Terminal

I have a production server. To login to the server I must use a .ppk file.  How to login with Ubuntu Terminal and .ppk file?  I tried this :  ssh -i location/file.ppk username@server-ip   but it is showing an error message.


Siunitx not running when I change computers

So I am using the siunitx package and it is throwing up an error at me when I use it on my computer. I know that the error isn't in my code as it has run with no problems on another computer.  The error that it gives me is as follows:  ("C:\Program Files\MiKTeX 2.9\tex\latex\siunitx\siunitx.sty" ("C:\Program Files\MiKTeX 2.9\tex\latex\l3kernel\expl3.sty" ("C:\Program Files\MiKTeX 2.9\tex\latex\l3kernel\expl3-code.tex") ("C:\Program Files\MiKTeX 2.9\tex\latex\l3kernel\l3pdfmode.def") ! Missing = inserted for \ifnum. <to be read again>                 - l.283   }  ?    I suspect that there is an error with how my computer is reading \l3kernel as this seems to be where it runs into the issue, however I have tried deleting and redownloading the file and it still throws up this same error.


How to tell if a sample comes from a distribution with infinite mean?

I observe a sample from a distribution that I expect to be the hitting time   $$\tau = \inf\{t>0| X(t)>a\}$$  where $X(t)$ is a Lévy process with $X(0)=0$ and $a$ is some constant. $X$ is not a Brownian motion and the experimental fit to the  is poor.   However, I do not need to know the exact formula for the law of $\tau$. For my needs I only need to know that the expectation of $\tau$ is infinite (as in the case of tau for a Brownian motion). Is it possible to formulate and test this as a statistical hypothesis?


Windows - Why my ram usage is so high ? - Poolmon tested

I have quite a big problem for playing cause I often reach 95% of ram used when I play, even if I have 8Gb in my computer.  What I don't understand is if I open Task Manager and sum everything, I never reach how much used ram it tell me I am using.  For example in this screen, it tells me 48% so around 3.8G used, but if I sum everything I don't even reach 1G.  So can someone explain me what is happening ?      PS: Done check with poolmon and the highest driver show a use of 0.1Gb of ram, so that is not the problem and this is not a duplicate !  PS2 : RamMap say exactly the same as task manager.


How to make a SUCCESSFUL persistent Ubuntu live hard disk drive or USB

I had the idea a few days back to make a portable hard drive that boots Linux. That way I can keep programs with me. The problem is, I can't install an OS because drivers won't work between computers. I tried this with UbuntuGNOME, and I got ERR2ERR3 when I tried to boot.  After researching online I found that a persistent Ubuntu live USB will work perfectly. The problem is, none of the USBs that I made have actually been persistent. I made one with UbuntuGNOME and Ubuntu Desktop. They boot fine, and I can change settings, install programs, and make files. Then, after shutting down and turning back on, all my changes were reverted.  Any help with creating a persistent Ubuntu live USB or any suggestions for what I am trying to accomplish would be greatly appreciated.


During start up beeping sound came out (sound came recently) When I log in, it types automatically with ]]]]]]]]]]], some time PLUS Has to press esc and backspace until the auto-type activity becomes idle for a while just in time to provide my password It actively switch from one application to another application and has to press esc button continuously until the activity becomes idle Scanning with Avast didn't find any viruses.   It’s very difficult to write anything on the text area or test box or anywhere. This happens every time, every day. But, at sometimes my system works normally and keyboard works normal but it last for 1 or 2 days (sometimes 1 week) only. And it again appears the same problem after few days. Someone suggested me that its a problem with Battery.  I believe this could be a virus since this same problem is happening on my brother’s laptop as well.   Please help


Freeze While Trying to Start Up Server After Install

I am trying to install Ubuntu Server 17.04 as a dual boot. I go through all the setup menus just fine. I reboot, and it asks me whether I want to boot into Windows or Ubuntu. I select Ubuntu and it begins to boot. The screen freezes at the words   fb: switching to nouveaufb from vesa vga   I am completely new to this. What do I need to do to fix this? Thanks.


I'm trying to get a grasp on the A* pathfinding algorithm. Using the image I attached.    If the green square represents the start, and red represents the end. wouldn't the algorithm bring me up towards the top of the grid, and then circle me back around, because of the wall?   It would seem the algorithm would never start by moving downward first because the F cost would initially appear more expensive?  Is this a problem with the basic manhattan heuristic? Or am I just missing something?


My child has chickenpox, am I infectious?

My 3-year-old has had chickenpox for about 2-3 days, but a close friend has just had a baby and I want to go and help. Is it possible that I am infectious, despite not having the illness? I had it as a child, so (hopefully) can't actually get it myself. Thanks!


I have my new Microsoft Surface and I was wondering whether it's possible to install pieces of software like MikTeX and TexMaker on this tablet. Does anyone know?


I have been out of touch with Java for a while and trying to create an array of generics and a bit confused.   For regular types I can do things like this:   String s[] = new String[10];   However if I have my own data type say a bag of integers and I want to define an array of Bag why can't I do this:   Bag<Integer> b[] = new Bag<Integer>[10];   Neither can I do this:   Bag<Integer> b[] = (Bag<Integer>) new Object[10];   The above doesnt work, how do I fix it?  EDIT: I saw the "duplicate" answer before I posted but I am unable to figure out how to use information in that answer to solve my problem. I have boiled down my issue to the simplest form and it doesnt appear to be the same.


This JavaScript file runs on one page but not on others, why is this?

I have a Jekyll blog  and have implemented navigation between adjacent posts (next and previous) at the bottom of each post page. I wrote a quick script that adds a hover effect on each image.  Here is the script:    $(document).ready(function() {     // animate home page post links on hover     $('.post-summary').hover(         function() {             $(this).animate({opacity: 1}, 100);         },         function() {             $(this).animate({opacity: .7}, 100);         }     ); });     It works on the main page fine but when you go to  it does not work at all, even though it is still included in the page source.  Why is this?


I am a fairly confident blender user, who has been using the software for about 1.5 years. I have recently updated from version 2.63 to version 2.70, but I have noticed that in version 2.70 the text alignment has changed.  Is there any way to change it back?    I have looked all over the internet and cannot find any way to change it in the User Preferences.


Stranded survivors have to cross world to get rescued. (Not Weber/Ringo's "Empire of Man" series)

I recall reading a story in the 1970s (USA paperback) about a small group of people (anywhere from a dozen to 50?) stranded on the wrong side of the continent from their rescue. (There was some time limit because either the rescue ship would leave on set date, or had to get there before their food ran out.) They were under a strict No Interference with the natives culture/tech/knowledge. (Like Star Trek's Prime Directive) So I believe they had to destroy or disguise all their high tech equipment/weapons before they start the journey. I think  the natives were similar in shape/coloring that the survivors could say they were natives from a distant land to account for the small differences. But don't remember for sure. The land is quite populated and probably a European Middle ages time period (1000-1400) I don't remember if they had firearms, or were only using swords, bows and spears. Pretty sure they had to interact with the natives much like in Weber/Ringo's "Empire of Man" series. (Sometimes diplomacy, sometimes fighting) The main thing I remember, was when they finally arrived and were rescued, they got in trouble because they had accidentally introduced a different style of harness similar to a horse collar or oxen yoke.   Previously the natives tied their carts to a collar like a dog collar which choked their beast of burden when they tried to pull heavy loads so it limited them to loads maybe only 10% of what the new collars/yokes could handle. (The survivors needed to transport heavy loads, which is why I think they needed to carry their own food.) Previously the native animals either pulled light carts or carried cargo on their backs like mules. The new collar/yoke allowed an animal to pull the load with their shoulders instead of their necks which is what makes the new collar/yoke so effective.


Obtaining Standard Errors in Optim() in R

I'm using a maximum likelihood estimation and I'm using the optim() function in R in a similar way as follows:  optim(c(phi,phi2, lambda), objf, method = "L-BFGS-B", lower = c(-1.5, -1.5, 0), upper = c(1.5, 1.5, 1), model = model_gaussian)  where objf is the function to estimate parameters given as:   objf <- function(pars, model, estimate = TRUE) {  model$T[is.na(model$T)] <- pars[c(1,2,3)]    if (estimate) { -logLik(model) } else { model } }   (The model$T given above is for the KFAS package)  Now, I would like to obtain the standard errors (in order to calculate t-stats) for the parameters I am estimating. However, apparently since this optimisation is a constrained maximum likelihood estimation (due to the "L-BFGS-B") I cannot use the Hessian matrix to obtain standard errors since it would not be mathematically correct, so this means I can't just add hessian=TRUE to the optim line.  For example, if I were using the BFGS(which is not restricted/constrained) rather than the L-BFGS-B method, to find standard errors is pretty simple:  opt <- optim(c(phi,phi2, lambda), objf, method = "L-BFGS-B", lower = c(-1.5, -1.5, 0), upper = c(1.5, 1.5, 1), model = model_gaussian, hessian = TRUE) standarderrors <- sqrt(abs(diag(solve(-opt$hessian))))   For this reason I thought I'd ask: what's the best way to obtain standard errors for my problem? What is the appropriate method to going about doing it? Thanks in advance.


Why is this statement false in python 3.0?

8 is int The above line of code statement shows false. Even though 8 is an int. How does this work? I would like to know how is operator works in this case. Thank you.


I made Ubuntu 14.04 (64bit) in my VM and I gave it 350gb of my 1tb HDD space and I did it fixed (not dynamically allocated) and i did it as a VDI and in my settings I set it to read the space as a SSD. I gave it 2 processors with 2000mb which is low so I was going to set up about 20gb of swap and swappiness of 50.  I was going to follow this guide to set up swap:    This is what I got:  oggie7797@oggie7797-VirtualBox:~$ sudo swapon -s [sudo] password for oggie7797:  Filename                Type        Size    Used    Priority /dev/sda5                               partition   2044924 14344   -1 oggie7797@oggie7797-VirtualBox:~$ free              total       used       free     shared    buffers     cached Mem:       2000792    1741236     259556      25060      13084     349624 -/+ buffers/cache:    1378528     622264 Swap:      2044924      14344    2030580 oggie7797@oggie7797-VirtualBox:~$    As you can see, it shows that I have swap even though this is a fresh install and all I have done is install Chrome-dev browser. So, now that I have given as much information that I can think to give I hope that someone can help me figure out how to either delete and create a fresh swap of my desired size or just simply edit this mysteriously preexisting swap to a larger size. Thanks in advance! :)


In a dual boot, why can I see and mount the Windows partition, labeled 'OS'?

Does it present a security threat in any form?


I am a beginner cyclist.So ,I want to know which things I have to do regularly.And what will be the time interval ?  Example :Pump,tuning etc.


Financial requirements to sponsor relatives visiting the Schengen area [Germany]?

I'm from India. My sister is staying in Stuttgart, Germany. She is inviting myself and our mother to visit her. I wanted to know, what should be the minimum bank balance required in my sister's account to invite us to Germany?


Table positioning forces weird spacing between paragraphs

I have quite a long table that almost fits one page. The table needs to be placed at the end of the section. The next section begins with a short paragraph so Latex always place the table next to that last paragraph.  I used the float package to force the table positioning but now the paragraphs on the page before the table are stretched out on the whole page.   How can I set the paragraphs to have a normal spacing between them and make it so that all the remaining space is just at the end of the page?   \documentclass{report}  \usepackage{graphicx} \usepackage{tabularx} \usepackage{booktabs} \usepackage{array} \usepackage[singlelinecheck=false]{caption} \usepackage{float}  \begin{document}  \subsubsection{the last paragraph} This is some text that makes up the last paragraph of this section.  \begin{table}[H] \captionsetup{position=top, skip=0.5ex} \caption{Caption of the table} \label{table} \begin{tabularx}{\textwidth}{l *{4}{>{\centering\arraybackslash}X}} \toprule Data & 1 & 2 & 3 & 4 \\ More data & 2 & 1 & 0 &  4 \\ Also data & 0 & 0 & 0 & 3 \\ \bottomrule \end{tabularx} \end{table}  \section{the next section} A very short parapgraph that fits on one page with the table.     \end{document}


How do I get the table names in a database into a combobox?

I have created a program in C#  that would allow the user to execute his query on a table that exists in a given database. Further, I want the user to select a table from the combo box on which he wants to execute his query. However, I am unable to fetch the table names from the database into the combo box. This is the code that I am using:      public partial class AddQuery : Form     {         public AddQuery()         {             InitializeComponent();             fill_combo();         }         void fill_combo()         {             string cmdstr = "Use Dev_Server";             SqlConnection con = new SqlConnection(@"Data Source=INPDDBA027\NGEP;Initial Catalog=Dev_Server;Integrated Security=True");             SqlCommand cmd = new SqlCommand(cmdstr,con);              DataSet ds = new DataSet();             try             {                 con.Open();                 cmd.ExecuteNonQuery();                 //comboBox1.Items.Add(dr);                 foreach (DataTable dt in ds.Tables)                 {                     comboBox1.Items.Add(dt.TableName[0]);                 }             }             catch (Exception ex)             {                 MessageBox.Show(ex.Message);             }         }        } }   Please Help.


Why are capacitors used in battery chargers

I'm looking at this IC:   And noticed under "typical application" a simple circuit diagram. What is the purpose of the capacitor that connects Vin directly to ground?  How does this affect the current/voltage being applied to vdd and the LED?  I have virtually no understanding of how/why capacitors are used in general. My very limited electronics experience has just about covered resistors. Would appreciate small words, and possibly somewhere to get further information (free online courses?)


I have Ubuntu 16.04. After some time of working, the terminal behavior has been changed:   "/" sign is not working "e" sign works the same as "↑" sign for  history navigation   What kind of mode is this? How to quit it?


Which form is correct (or more correct): reimplement or re-implement?  And to extend the question a little bit, are there any rules concerning both, e.g. re-scan or rescan, re-evaluation or reevaluation?  Edit:  The primary question is if both versions are correct (or which one is more correct from the English grammar's point of view). I know that both are in use, it's easy to do Google search for example to find out that "reimplement" is even more widely used than "re-implement". But in that case, why LibreOffice marks "reimplement" as incorrect? Is the construction informal? Incorrect? Because clearly is quite popular.  The second part of the question is somehow answered by the other question pointed to in the comment, e.g. I may use the hyphen if that makes the meaning more clear (which doesn't apply to this case IMHO).


Define path for packages in the LaTeX file (analog of \input@path or \graphicspath for \usepackage)

How to specify path for additional packages in the LaTeX file itself?  For graphics, you use \graphicspath{{a}{b}}, and then \includegraphics{file} finds b/file.pdf. EDIT: it should be \graphicspath{{a/}{b/}}, with slashes at the end.  For \input, you use \def\input@path{{a}{b}}, and then \input{file} finds b/file.tex. EDIT: \def\input@path{{a/}{b/}} is the answer, with slashes at the end.  Can I use a similar construction for \usepackage, so that \usepackage{mystuff} would find b/mystuff.sty?  I know I can mess up with system configuration or environment variables, but I prefer to specify this in the file itself, so that my files could be compiled on another computer.  I know that I can simply use \usepackage{b/mystuff}, but it generates a warning You have requested b/mystaff but the package provides mystuff, and it is less portable -- for example, it requires knowing in which specific folder mystuff.sty is.


Show that this family of measures is tight

Let $(\mu_t)_{t\in I}$ and $(\nu_t)_{t\in I}$ be families of finite signed measures on a metric vector space $E$ and $\mu_t\ast\nu_t$ denote the convolution of $\mu_t$ and $\nu_t$. Assume $(\mu_t)_{t\in I}$ and $(\nu_t)_{t\in I}$ are bounded in total variation norm $\left\|\;\cdot\;\right\|$, i.e. $$c:=\max\left(\sup_{t\in I}\left\|\mu_t\right\|,\sup_{t\in I}\left\|\nu_t\right\|\right)<\infty,$$ and $(\mu_t)_{t\in I}$ and $(\mu_t\ast\nu_t)_{t\in I}$ are tight, i.e. for every $\varepsilon>0$, there is a compact $K_\varepsilon\subseteq E$ with $$\max\left(\sup_{t\in I}\mu_t(K_\varepsilon^c),\sup_{t\in I}(\mu_t\ast\nu_t)(K_\varepsilon^c)\right)<\varepsilon\tag1.$$  Now I would like to show that $(\nu_t)_{t\in I}$ is tight as well, i.e. given $\varepsilon>0$, there is a compact $K\subseteq E$ with $\sup_{t\in I}\nu_t(K^c)<\infty$.  The obvious candidate is $K:=K_\varepsilon-K_\varepsilon$. We easily see \begin{equation}\begin{split}(\mu_t\ast\nu_t)(K_\varepsilon)&=\underbrace{\int_{K_\varepsilon}\mu_t({\rm d}x)\nu_t(\underbrace{K_\varepsilon-x}_{\subseteq\:K})}_{\le\:c\nu_t(K)}+\underbrace{\int_{K_\varepsilon^c}\mu_t({\rm d}x)\underbrace{\nu_t(K_\varepsilon-x)}_{\le\:1}}_{\le\:c\mu_t(K_\varepsilon^c)\:<\:\varepsilon}\\&<c\nu_t(K)+\varepsilon\end{split}\tag2\end{equation} for all $t\in I$.  If $\mu_t=\nu_t(E)=1$, we easily obtain $$1-\varepsilon<(\mu_t\ast\nu_t)(K)<\nu_t(K)+\varepsilon\tag3$$ and hence $$\nu_t(K^c)=1-\nu_t(K)<2\varepsilon\tag4$$ for all $t\in I$. We should be able to do the same in the general case, but how do we need to deal with the left-hand side of $(2)$ then?  It clearly holds $(\mu_t\ast\nu_t)(E)\le\mu_t(E)\nu_t(E)$, but that doesn't seem to help much.


My company is implementing employee badges. I'd like to purchase some equipment for a basic portrait format and then create a procedure for producing the portraits.  Could anyone describe the basic tools required for portrait shooting; is there a recommended a kit? Is there any advice about how to set up the shooting area?  I am starting with a DSLR that has an 18-55mm lens.


change directory in shell script based on prompt

I'm currently at /opt and running a small shell script. My "no" condition works perfectly, however, my yes condition doesn't work, I 'am still at /opt.  while true; do     read -p "go to log location ?" yn     case $yn in         [Yy]* ) cd /var/tmp/logs; break;;         [Nn]* ) echo "you are @ : " $PWD; break;;         * ) echo "Please answer yes or no.";;     esac done   Any help ??


Current thinking on the reasons for 3 particle generations

A question was asked a number of times on this forum, mostly in 2011-2013, of the theoretical reasons for exactly 3 generations of elementary particles. The answers mentioned that certain observed processes could not happen with less than 3 generations, but at that time almost all sources (except ) agreed that the specific reasons for exactly 3 generations were unknown.  My question is if there have been any theoretical developments lately suggesting a theoretical reason fo the number of generations being exactly 3.  The question is about potential recent developments, please do not mark it as a "duplicate" of questions asked years ago.


In the following script I want to perform the loading of a DLL only once when initializing  import ctypes import mathutils from ctypes import *  hmd = None  def poll():     if hmd is None:         hmd = ctypes.WinDLL("C:\\Program Files\\Blender Foundation\\Blender\\2.68\\scripts\\addons\\game_engine_rift\\openhmd.dll")     hmdPoll = hmd.poll     hmdPoll.argtypes = ()     hmdPoll.restype = ctypes.POINTER(ctypes.c_float)     pos = hmdPoll()     print(pos[0], pos[1], pos[2] ,pos[3])     bge.logic.rotation = mathutils.Quaternion((pos[0], pos[1], pos[2], pos[3]))  poll()   But I get this error:  Python script error - object 'Camera', controller 'Python1': Traceback (most recent call last):   File "rift.py", line 21, in <module>     poll()   File "rift.py", line 12, in poll     if hmd == None: UnboundLocalError: local variable 'hmd' referenced before assignment


Changing Vim indentation behavior by file type

Could someone explain to me in simple terms the easiest way to change the indentation behavior of Vim based on the file type? For instance, if I open a Python file it should indent with 2 spaces, but if I open a Powershell script it should use 4 spaces.


I've seen prior discussions of ending a sentence with "etc." and I know there should only be one period.  But what if the "etc." comes inside parenthesis which then end the sentence, such as:  .....blah blah blah (blah, blah etc.).  That looks awkward to me.  Because the period inside the parentheses is used for the abbreviation I don't think it suffices to end the sentence with it; so I'm thinking:  .....blah blah blah (blah, blah etc.)  is incorrect.    I know I could always simply write-out et cetera but I'm wondering if there's an actual rule for this.    Thanks in advance.    Ok, so multiple people have marked this as asked and answered.  Could someone please post a link to that, because I can't find it.    @tchrist: unicorns???    Never mind.  Found the link in the right margin.  Thank you.


Error messages when updating ubuntu 16.04 LTS

I am a total newbie to Ubuntu, and any Linux distro for the matter. So far I have been able to watch videos and research on google how to install all the programs I need but when I run sudo apt-get update I get the following messages.   W: Target Packages (Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55 W: Target Translations (en_US) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55 W: Target Translations (en) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55 E: The method driver /usr/lib/apt/methods/https// could not be found. W: The repository 'http://downloads.sourceforge.net/project/xenlism-wildfire/repo deb/ Release' does not have a Release file. N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. N: See apt-secure(8) manpage for repository creation and user configuration details. E: Failed to fetch https//://deb.opera.com/opera-stable/dists/stable/InRelease   E: Some index files failed to download. They have been ignored, or old ones used instead. W: Target Packages (Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55 W: Target Translations (en_US) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55 W: Target Translations (en) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list:55   I have tried apt-get clean and read  but that didn't help.  How can I fix it?


Is it safe to delete the old kernels from menu.lst?

When the computer starts, GRUB shows a long list of previous kernels in addition to the usual stuff, e.g.  Ubuntu 10.10, kernel 2.6.35-23-generic Ubuntu 10.10, kernel 2.6.35-23-generic (recovery mode) Ubuntu 10.10, kernel 2.6.35-22-generic Ubuntu 10.10, kernel 2.6.35-22-generic (recovery mode) [6 more similar] Ubuntu 10.10, memtest86+ Other operating systems: Dell Utility Partition Windows Vista (loader)   Is it safe to delete those extra "Ubuntu 10.10, kernel" lines from /etc/grub/menu.lst? Currently I have commented-out from the third one up to (not including) memtest86. But I wonder if they are ever needed for a particular reason?


Does Palpatine know that Yoda is dead in Return of the Jedi?

In the original trilogy, Palpatine did not meet with Yoda. But in the prequel trilogy they met several times. Does Palpatine even remember Yoda at the point when he saw Luke Skywalker on the Death Star II? He did not mention Yoda in Return of the Jedi.


How to enable MySQL client auto re-connect with MySQLdb?

I came across PHP way of doing the trick:  my_bool reconnect = 1; mysql_options(&mysql, MYSQL_OPT_RECONNECT, &reconnect);   but no luck with MySQLdb (python-mysql).  Can anybody please give a clue? Thanks.