I play a lot of "Call of Duty", and can see tracers for gunfire, missiles, care packages falling from helicopters etc. There is a lot of activity. I am curious to know the algorithm one would use, at a high level, to manage all this action when you have 20 people on a map shooting each other to death.   touches on the subject, but doesn't ask for a more in-depth answer as to how you the developers go about calculating and transmitting movement and collision detection for projectiles, be it missles, bullets, or any other object that is flying through the air in real-time.  How are trajectories calculated and transmitted to other players, in multiplayer?


Check if a class is derived from a generic class

I have a generic class in my project with derived classes.  public class GenericClass<T> : GenericInterface<T> { }  public class Test : GenericClass<SomeType> { }   Is there any way to find out if a Type object is derived from GenericClass?  t.IsSubclassOf(typeof(GenericClass<>))   does not work.


$x, a$ in $\mathbb R^n$, $A$ in $\mathbb  R^{n\times n}$. I'm trying to compute $d(x^T A x)/dx$.  I got, in the last step: (x^T A)^T + Ax. Somebody said that this should equal 2Ax. Why is that?  [Resolved.]


Question history attributed changes to me that I didn't make

I just made some minor edits to the text of .  I didn't edit the tags at all.  When I completed my edits, my edit showed as:    Now, I think those tags were present before I started my edit, and so were probably slipped in by the OP in their edit grace window.  I have no problem with that tagging, but I don't like seeing edits attributed to me that I didn't make.  So, what the heck?


How do I know what size tyres can I fit on my rims?

I have a hybrid bike with Alex DP17 32h rims (700c).  They still have the tyres that came with the bike on them, 40c konda's, but I'd like to replace them with some puncture resistant, narrower tyres with a slick centre strip since most of my commute is on road/tarmac path.  I can't find the rims on the Alexrims site, so how do I find out what tyres it is possible to fit?


I have 2 PCs at different locations: 1 at work & 1 at home.  The 1st PC is at home and it is a server and the 2nd PC is my work(client) PC.  At home I have setup VPN incoming connection on windows 7 and at work I am able to connect to my home VPN server via windows VPN Connections.  Problem I am facing is: When on my work PC I check my IP address via ipaddress.com, it doesn't show me IP of VPN server. How can I make it show that?


Suspend not working properly (cannot wake up) on Ubuntu 20.04 with NVIDIA

My problem is that I cannot suspend my computer properly. Technically I can, but when I come back and try to reopen it, it just doesn't work. My screen remains black with a blinking line, like a typical writing line _. My laptop is a . Here is the output of lspci: 00:00.0 Host bridge: Intel Corporation 8th Gen Core 4-core Processor Host Bridge/DRAM Registers [Coffee Lake H] (rev 07) 00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) (rev 07) 00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 630 (Mobile) 00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 07) 00:12.0 Signal processing controller: Intel Corporation Cannon Lake PCH Thermal Controller (rev 10) 00:14.0 USB controller: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller (rev 10) 00:14.2 RAM memory: Intel Corporation Cannon Lake PCH Shared SRAM (rev 10) 00:16.0 Communication controller: Intel Corporation Cannon Lake PCH HECI Controller (rev 10) 00:17.0 RAID bus controller: Intel Corporation 82801 Mobile SATA Controller [RAID mode] (rev 10) 00:1d.0 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #9 (rev f0) 00:1d.5 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #14 (rev f0) 00:1d.6 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #15 (rev f0) 00:1d.7 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #16 (rev f0) 00:1f.0 ISA bridge: Intel Corporation HM470 Chipset LPC/eSPI Controller (rev 10) 00:1f.3 Audio device: Intel Corporation Cannon Lake PCH cAVS (rev 10) 00:1f.4 SMBus: Intel Corporation Cannon Lake PCH SMBus Controller (rev 10) 00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH SPI Controller (rev 10) 01:00.0 VGA compatible controller: NVIDIA Corporation GP107M [GeForce GTX 1050 3 GB Max-Q] (rev a1) 01:00.1 Audio device: NVIDIA Corporation GP107GL High Definition Audio Controller (rev ff) 02:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981/PM983 03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 15) 04:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8822BE 802.11a/b/g/n/ac WiFi adapter 05:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS522A PCI Express Card Reader (rev 01)  I haven't seen a fix for this anywhere, so I was expecting someone to help me here. Thanks in advance!


Verifying some trigonometric identities: $\frac{\csc\theta}{\cot\theta}-\frac{\cot\theta}{\csc\theta}=\tan\theta\sin\theta$

Prove the following: 46. $\dfrac{\csc\theta}{\cot\theta}-\dfrac{\cot\theta}{\csc\theta}=\tan\theta\sin\theta$    I got as far as Right Side:   $\tan\theta\sin\theta$ to $\dfrac{\sin\theta}{\cos\theta}\dfrac{\sin\theta}{1}$ and then; $\dfrac{\sin^2\theta}{\cos\theta}$  Left Side:  $$\begin{align*}   \dfrac{\csc\theta}{\cot\theta}-\dfrac{\cot\theta}{\csc\theta} &= \dfrac{\frac{1}{\sin^2\theta}-{\frac{\cos^2\theta}{\sin^2\theta}}}{\frac{\cos\theta}{\sin\theta}-{\frac{1}{\sin^2\theta}}}\\ &= \dfrac{\frac{1-\cos^2\theta}{\sin^2\theta}}{\frac{\cos\theta}{\sin^2\theta}}\\ &= \dfrac{\frac{\sin^2\theta}{\sin^2\theta}}{\frac{\cos\theta}{\sin^2\theta}}\\   &= \frac{1}{\frac{\cos\theta}{\sin^2\theta}}\\ &= \frac{\sin^2\theta}{\cos\theta} \end{align*}$$ Thanks a lot!


Error while trying installation using sudo apt-get install

I'm getting this error while using sudo apt-get install command  E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it   How do I  solve it?


Unable to create files on large XFS filesystem

We have a Linux server with a 4 TB filesystem, which is used to store subversion repositories. There are many repositories, several of which have been in use for several years.   The disk was originally about 1 TB, but we started running out of space and increased it to 4 TB about a year ago. Now, people are reporting being unable to check in files to their repos. The error message is No space left on device.  The disk has about 1,5 TB free, and also reports having free inodes - and yet, it's not possible to create a new file on it. It's still possible to update old files, and intermittently some repositories will be updated, but the same repository may fail on the next attempt.


Show that $\lim_{n\to \infty}\sin{n\pi x} =0$ if $x\in \mathbb{Z},$ but the limit fails to exist if  $x\notin \mathbb{Z}.$ 1st part If $x\in \mathbb{Z}$ then $\sin{n\pi x}=0$ for all $n,$ giving the first part. Edit:  2nd part If $x\notin \mathbb{Z},$ I want to show that the limit doesn't exist. How to do that?


Do I travel "up" or "down" to London from north of the city?

I am travelling geographically down the country from north of the city of London. Do I state "I am travelling down to London" or do I state "I am travelling up to London" in reference to its capital city status?


Tried various solutions but still receiving the error code [RPC:S-7:AEC-0 XXXX-XXXX-XXXXX]

Once I was able to download apps from Google Play. But later, I disabled Download Manager for two days, then re-enabled it and opened Google Play to download apps but it started showing the following message whenever I tapped download.     Error while retrieving information from server. [RPC:S-7:AEC-0 XXXX-XXXX-XXXXX]     And XXXX marked letters change every time whenever I tap download.   (Click image to enlarge)      I cleared data and cache of Google Play, Google Play Services and Google Services Framework I removed the account and re-added it   But none of them worked.    I uninstalled Google Play updates, Google Play Services and reinstalled them --  didn't work as well.  I flashed my phone. So I got back my phone as new one -- it didn't work either.    I am just fed up now. I did everything as suggested. But none of them works. Please someone make solution to this problem.


I am preparing myself for ISTQB exam and I came across this question.     For the code fragment given below, which answer correctly represents   minimum tests required for statement and branch coverage respectively?  Discount rate=1; Fare = 1000; If ((person == “senior citizen”) and (“travel month = January”)) Bonuspoints = 100+Bonuspoints If (class==”first”) discountRate = .5; Fare = fare * discountRate;          a. Statement Coverage = 1, Branch Coverage = 2   b. Statement Coverage = 2, Branch Coverage = 2   c. Statement Coverage = 1, Branch Coverage = 3   d. Statement Coverage = 2, Branch Coverage = 4      Answer is A  But my answer is C the reason is flowchart I draw for it given below.    Straight forward from start to end One false for 1st 'if' second false for 2nd 'if'     My question is:   Should we draw an edge 'explicitly' for 'false' condition, if it is not given in question itself. How branch coverage is 3 here ?


I have a figure I'm trying to insert which is in landscape and I'm using the following (snipped) code:  \documentclass[12pt, oneside]{book} \usepackage{graphicx} \usepackage{wrapfig} \usepackage{lscape} \usepackage{rotating} \usepackage{epstopdf}  \begin{document}  \begin{figure}[ht]     \includegraphics{../figures/pics/DivLibPropProfile}     \caption{Property profile of the diverse library compared to the compound pool.}     \label{fig:PropProf} \end{figure}  \end{document}   When I compile this with pdfLaTeX the output behaves as I'd expect – page in portrait with the caption at the bottom but the figure in the "wrong" orientation.  However when I compile using LaTeX, the page is turned landscape with the figure now in the correct orientation but with the caption at what is now the left of the page rather than under the figure, which you should get using \begin{landscape}.    When I do use the landscape environment and compile with LaTeX the caption the whole page is turned upside-down and everything is wrong.  Any ideas how I can get the correct orientation of landscape figure on landscape page with the caption under the  (attached for reference)?  I also need to use LaTeX rather that pdfLaTeX for another package to function.


What is a physically precise definition of mass in Newtonian mechanics?

How do we get to know the concept of mass in Newtonian Mechanics? Like, from Newton's Second Law of motion we get : $\frac{d\vec P}{dt} = \vec F$ from here, $m\frac{d\vec v}{dt} = F$, defining $\frac{d\vec v}{dt} = \vec a $, we define mass $m = \frac{\vec F}{\vec a}$. Once again for a constant $\vec F$, we get, $\frac{m_{1}}{m_{2}} = \frac {v_{1}}{v_{2}}$. Which one (or any other way of defining mass) is correct physical way to define the concept of mass in Newtonian Mechanics?


How can I prevent a Spy-specific config from carrying over to other classes?

I have a script for Engineer and Spy. For Spy I have an ambassador script. How do I prevent the ambassador script from spy.cfg from carrying over to the engineer.cfg?


Same requirements as . But as soon as I try to set the style option, I get this error (Bibliography macro 'site' undefined):    MWE (comment the 3rd line in to reproduce the error):  \documentclass{article} \usepackage{filecontents} %\usepackage[style=chem-angew]{biblatex} % fails \usepackage[]{biblatex}  \DeclareCiteCommand{\supercite}[\mkbibsuperscript]   {\iffieldundef{prenote}     {}     {\BibliographyWarning{Ignoring prenote argument}}%     \iffieldundef{postnote}     {}     {\BibliographyWarning{Ignoring postnote argument}}%     \bibopenbracket}%   {\usebibmacro{citeindex}%     \usebibmacro{cite}}   {\supercitedelim}   {\bibclosebracket}  \begin{filecontents}{test.bib} @book{A01,   author = {Author, A.},   year = {2001},   title = {Alpha}, } @book{A02,     author = {Author, A.},     year = {2001},     title = {Alpha}, } \end{filecontents} \addbibresource{test.bib} \let\cite=\supercite \begin{document} Citing \supercite{A01, A02}. \printbibliography \end{document}   Output without style option:


multi tester showing 10 volts on in active wire

I have a line into a junction box and 14-3 going out to switch. tester shows 0 volts between ground and neutral on line in, however when I connect hot only at junction box I show 10 volts on all other wires including the ground.  Unsure why this would be, I completed all the connection and put the switches and light on and everything works but I still show 10 volts on the inactive wire at the 3-way switch. As I said it all works but I'm still not comfortable  with this and unsure why 10 volts is showing up


Converting lat-lon from degrees and decimal minutes to decimal degrees in PostGIS

Creating a geometry in Postgis is fairly simple:  ST_SetSRID(ST_MakePoint(longitude,latitude),4326);   These lat/lon should be in decimal degrees format like 33.02505 -96.70668  Is there a way/function to enter them in the degrees and decimal minutes format provided by NMEA $GPRMC sentences like 3301.5032 09642.4010?  Of course you can convert them in php or nodejs; but it would be easier (faster) to have it natively in Postgis.


Word for an event that will likely never happen again

I've read , but none of them are what I am looking for. I once read a book that used a word to describe an event that has happened in the past, but the odds were so astronomical that it will likely never happen a second time. The context I read these words in were the creation of the first life on earth (without any theological ideas). Basically, the text said that the scenario for the creation of the first living organism happened on a planet where conditions were just right by complete chance, and that the odds of this were so astronomical that it would likely never happen again anywhere in the universe over any length of time.  Sample sentence: "The creation of the first organisms was incredibly unlikely, the event can be called a _________ event, or an event that will likely never happen again."   I can't pretend to understand the validity of the claims by the text, but the words they used to describe these events were quite clever (and scientific sounding) that it would make a fun hyperbole.  I thought it was something along the lines of singularity event, but that doesn't sound quite right.


The refraction through hot air around a candle flame

Why the intensity of light is more around the region of hot air around the flame of candle in the shadow cast by the light from the collimated source ?    Most of the articles mention it is due to the refraction of light through hot air around the candle's flame. But I'm unable to understand how refraction make this happen.


How to demonstrate that there is no all-prime generating polynomial with rational cofficents?

It seems like there is no polynomial with finite variables known, which could generate all prime numbers, by integer assignments. Is there a proof that such polynomial can not exist and does anyone have one in his/her stack?


How do I make the taskbar visible again when playing Minecraft?

I cant see my task bar anymore and it makes going between windows hard, how do I exit Fullscreen? I have tried F11 and Ctrl+Esc. When I change it to off in the video settings, it just makes a small window and i cant maximize it.


MacBook Air battery not charging - very strange issues

I have been repairing a water-damaged MacBook Air 2015. Initially the machine would only boot with the battery disconnected and power connected, but then die after around 20 minutes. The MagSafe light did not light up at all but still provided power to the computer.    I replaced the battery, which made no difference. I replaced the logic board which then allowed me to boot with the battery & power connected. The MagSafe still did not light up and the the computer would die after around 20 minutes.   I have just now replaced the I/O board. The MagSafe still does not light up and the battery does not charge, but the computer runs as normal with all apps open and full backlight etc.  I have reset the SMC and PRAM to no effect but I can't think what I could possibly replace at this point. The only remaining original part is the ribbon connector that links the I/O and Logic board but that looks in good condition. Does anyone have any suggestions at this point?  System report says that there is 0 mAh charge remaining in the battery  Battery: Yes  Charging: No   It also says that cycle count is 729 which it definitely isn't as it's a new battery.  Any help appreciated.


Why is the size of a list less than the size of the objects that comprise it?

I have a question about space in the memory used by list and dict objects. My Python 3.7 shell shows:  >>> import sys >>> list_ = [] >>> sys.getsizeof(list_) 64 >>> dict_ = {} >>> sys.getsizeof(dict_) 240 >>> list_ += dict_, >>> list_ [{}] >>> sys.getsizeof(list_) 96   I don't understand what is going on.     The list object takes 64 bytes of memory (what's shown in shell) + 8 bytes for each element.   The dict object takes 240 bytes of memory.   So, after adding the dictionary as an element, the list should take 64 + 8 + 240 = 312 bytes.     Why did the memory taken by the list increase by only 32 bytes?  What happened to the dict's 240 bytes memory? And why did the amount of memory used increase by just 32 bytes?


for two primes p and q, $\sqrt{p}$ +$\sqrt{q}$ is irrational?

on the contrary, let us suppose: $$\sqrt{p} \ + \sqrt{q}\ \ is \ \ a \ \ rational \ \ number,$$ so, $$\sqrt{p}  + \sqrt{q}  = \frac{a}{b} ,\ where\ gcd(a,b) = 1\ and\ b \neq 0$$  upon squaring both sides and some rearrangements, we get $$b^2(p + 2\sqrt{pq} + q) = a^2$$  since b | LHS, we can say that b | $a^2$ if b > 1, then there exists a prime c, such that c | b. therefore c | $a^2$ and c | a. so here we can say that gcd(a,b) $\geq$ c. which leads to a contradiction. Therefore we conclude that $\sqrt{p} \ + \sqrt{q}$ is irrational.   Now the problem I am facing with this method is what happens when b = 1? Suppose when b = 1, the above equation becomes: $$(p + 2\sqrt{pq} + q) = a^2$$ when b was greater than 1, we were not concerned with the values of p and q.  but in this part, how do we prove that the left-hand side can never be a perfect square, even if p and q are distinct or the same?


My computer doesn't recognize the monitor's resolution on some VGA cables, what's going on?

My Mac doesn't recognize my TV's resolution on (so far) 3 VGA cables I've tried but it works just fine using other seemingly old VGA cables. My roommate had the same experience on Mint Linux.  What's the difference between VGA cables? What should I look for in a VGA cable that I buy? Are those still being made?


Why can we get eigenvalue through solving $det(A-\lambda I)=0$?

In many notes, I see  $A\vec{v}=\lambda \vec{v}$  $(A-\lambda)\vec{v}=\vec{0}$  $det(A-\lambda I)=0$  How to get line 3 actually?  Thanks.


Geodesic equation from the proper time integral

This is something that has been bothering me for a little while. The usual procedure that I've seen is to write the proper time as the line integral $$\tau=\int_\gamma d\tau$$ along some curve $\gamma$. That curve that minimizes this is a geodesic (assuming Levi-Civita connection here). The definition $d\tau^2=-g_{\mu\nu}dx^\mu dx^\nu$ leads to $$\frac{d\tau}{d\lambda}=\sqrt{-g_{\mu\nu}\frac{dx^\mu}{d\lambda}\frac{dx^\mu}{d\lambda}}.$$ So, using , we have $$\int_\gamma d\tau=\int_{\lambda_i}^{\lambda_f}\sqrt{-g_{\mu\nu}\frac{dx^\mu}{d\lambda}\frac{dx^\mu}{d\lambda}}d\lambda,$$ where $\gamma(\lambda_i),\gamma(\lambda_f)$ are the beginning and end points of the curve. It can be easily verified that this is parameterization invariant. It is standard to normalize $\gamma$  $$g_{\mu\nu}\frac{dx^\mu}{d\tau}\frac{dx^\nu}{d\tau}=-1.$$ Thus it would seem that $$\int_\gamma d\tau=\int_{\lambda_i}^{\lambda_f}\sqrt{-g_{\mu\nu}\frac{dx^\mu}{d\lambda}\frac{dx^\mu}{d\lambda}}d\lambda=\int_{\tau_i}^{\tau_f}d\tau=\tau_f-\tau_i.$$ Thus $\gamma$ does not even play a role it seems. Thus when we introduce a one-parameter family $\{\gamma_\varepsilon\}$ and take the variational derivative, we get 0 arbitrarily. What gives? How can we vary this integral without changing the bounds?


Update Ubuntu 16.04 to 18.04 on Dell PowerEdge R630

I have a PowerEdge R630 on Ubuntu 16.04 LTS and want to update it to ubuntu 18.04. In 16.04. PowerEdge R630 is in support list of ubuntu but in Version 18.04. DELL PE R630 is not listed, should i nevertheless updating to 18.04 or is there a high risk?


What happens if 2 separate abilities require you to sacrifice a creature?

If i have two cards that force opponents to sacrifice every upkeep like for example  "At the beginning of each opponent’s upkeep, Mogis deals 2 damage to that player unless he or she sacrifices a creature."  And  "At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature or pays 3 life."  Does the oppenent have to sacrifice twice? Or if they sacrifice Mogis's ability have they not allowed me to draw from indulgent tormentor?


Derivation of the compensating resistor in integrator with DC gain control

Hi all in EE stackchange, I wonder how the compensating resistor (\$R_3\$) in integrator with DC gain control equals \$R_3 = R_1 || R_2\$, which is to offset effect by the input bias current. I was trying to derive it by same way in Razavi's textbook but I can’t reach the result of compensating resistor \$R_3=R_1 || R_2\$ (As depicted in below Figure) It would be very appreciated if someone let me understand this. Thank you in advance!


I have a simple class named "Trida"  public class Trida {     public double[] append(double[] pole1, double[] pole2){         int length = pole1.length + pole2.length;         double[] pole3 = new double[length];         for (int i = 0; i < pole1.length; i++){             pole3[i] = pole1[i];             pole3[i + 1] = pole2[i];         }         return pole3;     }  public static void main(String[] args) {         Trida trida = new Trida();          double[] pole1 = {1.0, 3.0};         double[] pole2 = {2.0, 4.0};         System.out.println(trida.append(pole1, pole2));     }   When I run this code, terminal said [D@15db9742, but I want print field like that - [1.0, 2.0, 3.0, 4.0] Can you help me?


I have two continuous distributions and I am trying to compare them using KS test using R Studio with the code below:  f1 <- "filename1" f2 <- "filename2"  readDataFromCSV <- function(filename) {   packetsData <- read.csv(file=filename, header=TRUE, sep=",")   return(packetsData) }  pd1 <- readDataFromCSV(f1) // x pd2 <- readDataFromCSV(f2) // y  timecdf1 <- ecdf(pd1$Time) timecdf2 <- ecdf(pd2$Time)  colors37 = c("red","blue","brown","orange","black","purple", "green","cyan", "navy", "pink", "maroon", "grey", "black", "coral", "lavender", "magenta", "yellow", "azure", "bisque", "darkcyan") ksResult <- ks.test(pd1$Time, pd2$Time, alternative = "greater") print(ksResult)   plot(timecdf1, verticals=TRUE, do.points=FALSE, col=colors37[1], ylab = '', xlab='Time(sec)');par(new=TRUE) plot(timecdf2, verticals=TRUE, do.points=FALSE, add=TRUE,col=colors37[5])   When I apply the KS test it results in the following:      Two-sample Kolmogorov-Smirnov test  data:  pd1$Time and pd2$Time D^+ = 0.015708, p-value = 0.9213 alternative hypothesis: the CDF of x lies above that of y   And when I draw the ecdfs of the values the results are shown below:  The 'x' represents the red line on the graph and 'y' represents the black line.  I don't understand why the graph shows x below the y. On the other hand KS test of the x and y shows a high value of p indicating that x should lie above y.   I am missing something trivial in interpretation of the KS test.


Ubuntu Core: Is it possible to use an external encrypted file system?

I am playing with a Raspberry Pi 3 and Ubuntu Core. One of the requirements I have for taking it into a more serious use, is the capacity to manage encrypted drives, like mounting them during the boot sequence.  I could not find cryptsetup on the Snap Store. Is it possible to mount encrypted drives on Ubuntu Core during boot in some other way?  Edit: I'm not looking for a full encryption of the Ubuntu Core filesystem, my purpose is to mount an existing encrypted drive as part of the Ubuntu Core filesystem.  Edit2: As mentioned before, I'm not looking for a fully encrypted Ubuntu Core system. I want to mount externally encrypted drives. I'm doing exactly that with Rasbpian, and I want to know if it is possible with Ubuntu Core


I have finished my scene but the colors for my objects are not changing. they are still the default color greyish. I finished creating the scene before making color changes, is there a certain order I should follow to change colors?


FYI: These comments (SO) are too wide:   I believe it's specifically the strikeout comment, as when I remove the strikeouted text (firebug) the layout returns to normal:   I know there are issues with the comment widths as they're fluid, but this one (and others like it) could be fixed by removing ability of strikeout from comments.  Comments should be short/simple for what one wants to say, not go into what one didn't want to say (sorry Olli)  I'm using: Iceweasel 24.7.0 on Deb wheezy (7.6)


Is there a way to blacklist sites containing specific keywords? like for example "porn, xxx.. sex". My cheap router can only block 5 specific domains but not sites containing some keywords.    Do you know a software (windows) which runs in the background and does not show any "SITE BLOCKED!" errors in the browser? It should not load the site at all or at least show only blank page.    It can also be a plugin for chrome. (I tried some already)


What Ubuntu-compatible software is available to remove shaking from a video?

I've got some some home movies that look great, but my video camera doesn't have one of those fancy new stabilizers. Is there extant end-user software (preferably FLOSS) I could use to removing the shaking?


Better way to sift through favorites and search correct fit to the problem at hand

Can there be a search option when trying to go through my "Favorite" questions? If I have a lot of questions marked as favorite, it is quite a task to go through them and check if I have already an answer to a question that I currently have.  We can have a search box, where we can type tags that might describe the problem we have at hand and it returns the list of favorite questions which "might" fit our description thereby reducing the time required to zero in on the correct "answer" question.  It will help find/manage content better, IMHO.  A related question:


Can this statistic be shown not to be sufficient for $\theta$?

This problem comes from , who do not rigorously demonstrate (in their solution key) that the statistic is not sufficient.  Let $X_1,\dots,X_n$ be a random sample from a population with PDF $f(x|\theta)=\theta x^{\theta-1} \cdot 1_{\{x\in(0,1)\}}$ for $\theta>0$. Show that $\sum_i X_i$ is not sufficient for $\theta$.  If you write out the PDF $p(\vec{x}|\theta)$ of the random sample, it is clear by the factorization theorem that $\prod_i X_i$ or $\sum_i \log(X_i)$ are sufficient for $\theta$; the PDF $p$ also suggests $\sum_i X_i$ is not sufficient for $\theta$. However, to rigorously demonstrate this, we need to analyze $p(\vec{x},\theta)/q(T(\vec{x},\theta)$, where $p$ is the distribution of sample $\vec{x}$, $q$ is the distribution of the statistic $T(\vec{X})=\sum_i X_i$. But finding the distribution of $T(X)=\sum_i X_i$ seems impractical. I have observed that $f$ is the PDF of a Beta($\theta$,1) distribution, but checking online, the distribution of the sum of Beta random variables doesn't appear to have a closed form. Are there any alternative routes (e.g., showing there is no factorization involving $T(\vec{X})$)? Did C&B leave out a full explanation that $\sum_i X_i$ is not sufficient because none actually exist?


Does somebody get the same badge twice or more?

How does people have hundreds of badges, when the list shows(When you click on Badges tab) few?


Lightning Component - Close Case Button not working

I have began developing a button to automatically close the current case but I can't seem to get it working. I have tried a few different approaches but would someone be able to point me in the right direction.  As it stands the button does nothing, I feel like im on the right track, looking for someone who has done something similar with regards to updating fields from within a lightning component.   CMP  <aura:component controller="AmexComm_SecureMsgController" implements="forceCommunity:availableForAllPageTypes,force:hasRecordId" access="global"> <aura:attribute name="record" type="Case"/> <aura:attribute name="caseStatus" type="String"/> <aura:attribute name="caseId" type="String" default="{!v.recordId}"/>  <aura:handler name="init" value="{!this}" action="{!c.doInit}"/>   <button class="slds-button slds-button--neutral newsbutton" style="float:right"  onclick="{!c.closeCase}">Close Case</button>   AmexComm_SecureMsgController   @AuraEnabled     public static Case getCase(Id caseId){         return([Select id, Atrium_Subject__c, Atrium_AmexSubject__c, Status, Atrium_Message_Status__c, Contact.Name, ContactId, CreatedDate, Message_Number__c, LastModifiedDate, Description__c,                 (SELECT id, Name From Attachments)                                 From Case Where id=:caseId]);     }     @AuraEnabled     public static Case closeCase(Case caseA){        update caseA;        return caseA;     }   Controller  { doInit : function(component, event, helper) {     component.set("v.isError", false)     component.set("v.showEditView", false);     component.set("v.errorMsg", "");      var action = component.get("c.getCase");     action.setParams({         caseId : component.get("v.caseId")     });      action.setCallback(this, function(a) {         if (a.getState() === "SUCCESS") {             component.set("v.record", a.getReturnValue());             helper.getStatusPickListValue(component);         }     });      $A.enqueueAction(action); },  closeCase : function (component, event, helper) {     var action = component.get("c.closeCase");     var Status = component.get("v.record.Status") //get value of field     //console.log("Status: " Status);     action.setParams({Status : Closed});      $A.enqueueAction(action); },   Helper  getStatusPickListValue : function(component) {          var action = component.get("c.getCaseStausPickList");         action.setCallback(this, function(response) {             var state = response.getState();             var hasImg = false;             if (component.isValid() && state === "SUCCESS") {                  var statusPickList = response.getReturnValue();                 component.set("v.lstCaseStatus", statusPickList);                  console.log('status picklist ::', component.get("v.lstCaseStatus"));             }         });         $A.enqueueAction(action);      },


What exactly is NASA's proposed mechanism for "propellantless" "EM Drive" propulsion?

Of course, this question runs perilously close to this site's prohibition against discussing non-mainstream physics. However,  about what is acceptable and what is not acceptable regarding non-mainstream physics, says that it's okay to ask for an evaluation within mainstream physics of a new concept or paradigm. I believe my question falls under this heading. The new concept is that it might be possible (counter-intuitively) to accelerate a body in a vaccuum without a traditional propellant. My understanding from  (paragraph starting "Dr. White proposed") is that the engineers at NASA have some kind of theory which is supposed to fit into mainstream physics about how this would work. But I'll understand if people vote to close.  The article I've linked to is not technical, and provides no technical references. My Google-fu has not managed to uncover a more technical description anywhere (I can't even find a homepage for the group doing this research). So   Question: What exactly is the theoretical mechanism that NASA (in particular, Sonny White, in particular, not Roger Shawyer) is proposing? And where can I read about it?  The proposal is apparently precise enough to build a computer simulation off of it (see near the end of the article, the section labeled "Progress Update"), so I'm assuming that it must be intelligible.  For example, here's something that might be the sort of thing they're talking about. Imagine that on your spacecraft you have a gamma-gamma collider (powered by a nuclear reactor or solar panels or whatever). When the photons collide, they create lots of high-energy electron-positron pairs spraying out in all directions. By clever design of the hull of your spacecraft, let's say that you preferentially readsorb electrons / positrons moving toward the bow of the ship (e.g. put a big lead block to the bow of the collider). Then you will generate momentum going forward. Your propellant particles have been bought from the vaccuum.  Now, the EM fields involved in the NASA setup are nowhere near this strong, so the mechanism can't be quite this. The article I linked to says something about virtual particle-antiparticle pairs, so maybe the proposal is that the "propellant" is made up of waves in the electron field which are not localized as particles?  EDIT Earlier questions have focused on whether the proposed effect would violate conservation of momentum. My assumption is that if we actually look at NASA's proposed mechanism, we will see that it's not violating conservation of momentum, just sending that momentum off into "new" particles, as in the example version I sketched. I'm really mostly interested in seeing the actual proposal, so maybe this question is best viewed as a reference request.  EDIT I'm disappointed to see this question marked as a duplicate. I'm asking for a specific link, and I haven't seen that link, nor have I seen a definitive claim that the link I'm looking for doesn't exist.


19 hrs layover in Frankfurt. Have US and Canada valid visa . Can go out of airport without transit visa

Do i require a transit visa during my 19 hr layover in Frankfurt? Travelling with family to Toronto. Having valid US Visa also. We are Indian family.    Can we go out of Airport during long layover and if yes do i require transit visa for it or not? Or just hotel booking will help us getting shore pass like that given in Japan? Secondly if we don't go out what are options on airport for 19 hrs layover?


''EFI boot partition'' and ''biosgrub'' partition

Why do I need these? I have installed Ubuntu under a non UEFI (master boot record) and have installed Ubuntu with no 'biosgrub' and it works fine, whereas other times I am asked to make a 'biosgrub' partition.  I have no idea why sometimes I need it and others I don't (these have both been on the same system).  And the same thing happens when I use UEFI (GUID Partition Table).  The only difference is I am asked to make a 'EFI boot partition', but as with the 'biosgrub', sometimes I am asked to make it and sometimes I am not asked to make it.  For my current install I was asked to make one but I didn't and my system is fine. There is no change in the system, same hardware, BIOS etc... Could anyone shed light on this?


Let $y(x)$ be a continuous solution of the IVP:  $$\left\{\begin{eqnarray}y'+2y &=& f(x)\\y(0) &=& 0\end{eqnarray}\right.$$  Find $y(\dfrac{3}{2})$.  $$f(x) = \begin{cases} 1 &\text{$0\leq x\leq 1$} \\ 0 &\text{$x>1$} \end{cases}$$  My try :  I solved it in two cases:  Case 1:$x\in [0,1]$ taking $y^{'}+2y=1$ and using $y(0)=0$ on solving I get $y=\dfrac{1-e^{-2x}}{2}$  case 2:$x>1$ taking $y^{'}+2y=0$; I get $\ln y=-2x+c$ where $c$ is a constant.  what should I do now?


C++ call template function of class as template parameter

I have error "expected primary-expression before 'int'" and "expected ';' before 'int'" in this code, does anyone know why?  struct cpu {     template<class T> static void fce() {} };  template<class _cpu> struct S {         void fce()      {           _cpu::fce<int>(); //error: expected primary-expression before 'int'                           //error: expected ';' before 'int'     } };  int main() {     S<cpu> s;     s.fce(); }


How do I disable S to allow myself to launch Sublime?

I've been using Sublime Text 2 quit a bit lately and want to make it as easy to launch as Terminal.   I've done the following so far:    I went into System Settings > Keyboard > Shortcuts > Windows and disabled the shortcut for Toggled Shaded (Ctrl + Alt + S). I used gconf-editor to add <Control><Primary><Alt>S under apps/metacity/global_keybindings/run_command_1 and pointed it to /usr/bin/sublime under apps/metacity/keybinding_commands/command_1.  I went into dconf-editor and changed the Toggle Shadows shortcut to <Control><Super>S under org/gnome/desktop/wm/keybindings.    I am still unable to launch Sublime with the shortcut Ctrl + Alt + S, and normal windows still keep being toggled with the shortcut. I'm using Ubuntu 12.04, any suggestions on what I am doing wrong?


A Inquiry About Infinitive-To and Its Role As A Subordinator or An Auxiliary

If you're interested in grammar, as I am, I am sure you have delved into a thought process about infinitive to, and like me, you have probably questioned what it is, or what it could be defined as. My mind always wants to place it in the Eight Parts of Speech, and I know this is foolish of me to some regard, so I stray from it, but I still wish to designate it under something that can be explain it. So, this is the motivation for this post, this question: What is the infinitive to, and why?  Here are my thoughts: There are three real possibilities, going back through the times. First, we can say that it is part of the verb that comes after it (to go, to run, etc.). This could be supported by the claim that you are not supposed to "split" infinitives ("To boldly go"), but only that.   Secondly, we could consider it a subordinator. I came across this designation most recently in my studies of modern and transformational grammar. As of right now, it is still the one I accept, especially as a result of the trend of designating more phrases as clauses. It works, except it's weird. Do we call this a unique subordinator as a result of how it operates? For example, to-infinitive clauses call for non-finite verb forms, which typically have an implied subject as a part of their clause. For example, "I want to go to the store." In the infinitive clause, "I" is the implied subject, as a understand. So, again, this works. However, things get a little weird when other subordinators come into play. For example, "I'm excited for you to win the competition." Now, if I'm right, those of you will say that "for" is a preposition here, as a result of the new-grammar stuff, but I'm going to count it as a subordinator, as defined by my own beliefs and that of a lot of other grammars. So, how do the clauses work in such a sentence? According to transformational grammar, "for you to win the competition" is defined as an ordinary clause. So, does that mean that it also contains a secondary clause within itself (the infinitive clause part)? If so, how do those two clauses work in conjunction to each other when one is so integrated? "For you to win the competition" looks to just be one clause, but if that's the case, doesn't "to" have to represent something else?  This moves us on to the third way to look at things, which is to consider "to" as auxiliary verb, a defective one at that. There are a lot of things to support this, and it even allows for the split infinitive. Furthermore, it calls for a non-finite verb form to follow, like an auxiliary. But, as I said before, it's defective in the way that is all it can function as.  As I said, I still accept to as a subordinator, but I want to be proven wrong or right. Wrong by showing evidence of it being something else, or right by showing how clauses operate when it seems to be layered up.


Beamer in LyX: no sperator option avaiable

I have been using beamer in LyX for a while now. Love it. But I just got a new computer, istalled LyX again and when I create a new beamer file (or open an old one) the "separator" option that is used to end a frame is not avaiable.  I do not know if there is something wrong with my installation or if I should install some package, or something else.  Has anybody ever run into this problem as well?  Thank you for the help.  Edited: Thank you for the answers, I basically need to update lyx on the other computers now.


Trigger an action only once when a condition is met, not every frame after that

I want to avoid check if a particular function is returning true, and perform an action (Set Active) once it does return true for the first time.  Currently my code looks like this:  Update() {         if ( IsTaskCompleted() ) {             object.SetActive( true );     } }   SetActive gets called every frame after the task is completed. How can I avoid this, and call SetActive only once?


What to do if you forgot your lockscreen password?

How would I go about forgetting my lock-screen password? What can I do to get back in? This is about the iPhone 4, 4S and 5. More of a How-To question, someone I know forgot their password.


Misalignment in top bar on mobile web on sites with long names

With the roll out of the new top bar on Interpersonal Skills SE I'm seeing a slight misalignment. Looks like the top bar is a bit wider than the rest of the body:    I'm seeing this in on an Android phone using Chrome.  On other systems/with other preferences, part of the top bar is just invisible (though it can be found by scrolling). These screenshots were made with Firefox 57.0.4 on Android 6.0, 720×1280, ~294 ppi:


How to determine if the current entry of Java Map is the last

I need a key-value pair and I need to iterate over it, but I need to remove the & from the last iteration.  My key-value Map object is defined as:  private Map<String, String> additionalAttributes = new HashMap<String,String>();   I perform my iteration as such:  for(Entry<String,String> i : additionalAttributes.entrySet()) {     attributes += i.getKey() + "=" +i.getValue() + "&"; }   Is there any way I can determine if the current entry i is the last entry in the map? The map will vary in size and contents each time it's run so I need a dynamic solution.


Recent stories stemming from the  disclosure about billionaires and effective tax rates describes a strategy where billionaires borrow eye-popping sums of money, using their stock equity as collateral. The article lists Larry Ellison with a nearly $10B line-of-credit secured by Oracle stock, Elon Musk pledged $57B worth of stock for personal loans, and Carl Icahn with "only" $1.2B in loans from Bank of America (among other loans). I understand how taking a loan avoids selling shares and triggering taxes on capital gains. What I don't understand is how these loan positions get closed out. Are they merely deferring taxes for some number of years, eventually selling assets to pay off the loans and paying capital gains at that point? Or do these loans just sit on the books until the the borrower dies and are paid out of the estate? Are they structured in such a way that the loans are paid by heirs who benefit from a stepped-up basis and thus incur no capital gains?


I can't install anything with apt-get and can't add repositories either

I use a program called SimpleScreenRecorder to record videos for YouTube. I was having a problem with it when trying to launch it so I decided to reinstall it. When I try to run the command sudo add-apt-repository ppa:maarten-baert/simplescreenrecorder it tells me this:  Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 91, in <module>     sp = SoftwareProperties(options=options)   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 109, in __init__     self.reload_sourceslist()   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 599, in reload_sourceslist     self.distro.get_sources(self.sourceslist)       File "/usr/lib/python3/dist-packages/aptsources/distro.py", line 89, in get_sources     (self.id, self.codename)) aptsources.distro.NoDistroTemplateException: Error: could not find a distribution template for Ubuntu/xenial   This does not happen when I run sudo apt-get update and it says this (just in case something is wrong here too)  Hit:1 http://archive.ubuntu.com/ubuntu xenial InRelease Get:2 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB] Get:3 http://archive.ubuntu.com/ubuntu xenial-security InRelease [102 kB] Fetched 204 kB in 1s (178 kB/s)                              Reading package lists... Done   When I try to run sudo apt-get install simplescreenrecorder it gives me this output:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package simplescreenrecorder   and SimpleScreenRecorder does not install. The exact same thing happens when I try to install LiVES even down to the same outputs and I had the same problems.  I am running Ubuntu 16.04.2


Does the caster get hurt by the Conjure Barrage spell?

The description of the  spell states:     You throw a nonmagical weapon or fire a piece of nonmagical ammunition   into the air to create a cone of identical weapons that shoot forward   and then disappear. Each creature in a 60-foot cone must succeed on a   Dexterity saving throw.   But I am slightly confused on the wording... From what I understand:   You Shoot an arrow (or another object) into the air The arrow bursts into a multitude of itself at a point in the air and falls back down, filling a cone of 60 feet in diameter.  Everyone in that circle has to make a Dex save or get hurt.   Am I reading this wrong, or is the ammunition falling on top of you, making you have to make a Dex save to protect yourself from your own attack?


Why do you need to apply hash over DH shared key?

I`ve read multiple times that it is not safe to use the shared key resulted from DH key exchange directly and that you need to do a KDF or hash over it and then use the result as a key. Why is it not safe to use the shared key directly?


I'm wondering if anyone knows of a document viewer that has a menu of some kind that shows all my open documents.  I typically have anywhere between 5 and 20 PDFs open when I'm doing research, and using Super-W or clicking the dock icon to "explode" all the windows is totally useless.  On my Mac, most applications have a "Window" menu that shows all open documents in a nice list, like this:   Any thoughts?


I'm trying to import an Access file (.mdb) to QuantumGIS. This database comes from a geodatabase from ArcGIS.  Can someone explain me how to do it?  I tried to import from Add Vector Layer > Database > ESRI Personal Geodatabase ...  But from there, I am confused...  What are the next steps? Do I have to connect it to an existing shapefile?


How to get clear bone broth - without canning

I like how canning bone broth causes the broth to go clear. My recipe for bone broth is to cover bones with water and simmer on low for 4-5 hours.   I then strain it several times with the last straining through cheesecloth.  The broth is milky in appearance at this stage. The left-hand jar was made at the same time as the right hand jar.   I just didn't have room in the canner to do all the jars in 1 batch, so it went in the fridge instead.  After the left-hand was canned, the broth turned clear as well. Is there a way to get clear bone broth without pressure canning it?  Taste wise, both jars are the same but I find the broth in the right hand jar substantially more appetizing than the left hand jar. I should point out that when the picture was taken, the broth in both jars was jelled.  They retain the state of milkiness or clarity when heated though.


Which is more polite, "Would you" or "Could you"?

Suppose you want to ask someone to do something, say to tell you the way to a station. Which is more polite, "Would you tell me the way to the station?" or "Could you tell me the way to the station?"?


I need a circuit that allows current to flow in both directions through a load, and I came up with this. Is it good or is there a better way?

this is one of my first circuit "designs" (quotes on since it's simply switches). I need current to be able to flow in both directions through a certain load, and the direction of travel should be electronicaly commanded. This is what I thought of:         – Schematic created using   Sorry if it's too messy. This way, making pins 1/2 high (but never both at the same time) makes current flow in each direction. Is this a good way or is there a simpler one?


How to stop ASP.NET from changing IDs in order to use jQuery

I have this label control in my web page  <asp:Label ID="Label1" runat="server" Text="test"></asp:Label>   And when the page rendered the id of the control changes to something like this    test   How can I stop asp.net from changing IDs in order to perform a jQuery operation like this  $('#label1').html(xml);


Bounded sequence of functions uniformly converges to bounded function

I'm working on the following question:     True or False (and explain why or give counterexample). Suppose $(f_n)$ uniformly converge to $f$. If each $f_n$ is bounded then $f$ is bounded.   I think this is true, but I'm having trouble showing it. In particular, suppose the $M_n$ is a bound for each $f_n$ then: $$|f_n-f| < \epsilon \\  -f_n - \epsilon < f < \epsilon + f_n  \\ -M_n - \epsilon < f < \epsilon + M_n$$  There's nothing controlling the growth of the $M_n$'s though. If $f_n$ are uniformly converging, I think the bounds should be close too, but I'm having trouble arguing this. Thoughts?   question is similar, but both answers skip the key detail that I'm hung up on.


What is the best online javascript/css/html/xhtml/dom reference?

I'm a front-end developer and I was looking for opinions about the best all-round online documentation for javascript/css/html/xhtml/dom/browser quirks and support. I've tried Sitepoint, Quirksmode, W3Schools but all of these seem to be lacking in certain aspects and have been using them in combination.


Being always confused, I would appreciate which is correct usage of "part of" or "a part of" in the following case with brief explanation as to how I should differ either. I have checked dictionaries and articles/speeches on the websites.  There are a lot of young people who want to be a part of the movement(or part of the movement).


I need to include two abstracts (english and spanish) with their respective keywords, I am using the package apa6 but these only put the latest \abstract{} text.  How can I fix this?  \documentclass[jou,apacite]{apa6} \abstract{El tema de la evaluación educativa ...} \keywords{evaluación, aprendizaje, decreto 1290 de 2009.} \abstract{ The issue of educational evaluation is one } \keywords{assessment, learning, decree 1290 of 2009.} \begin{document} ... \end{document}


I use Ubuntu 12.04 LTS on my PC because Windows is quite laggy on it. I want to know whether I should upgrade from 12.04 LTS to 14.04 LTS.  My system specs are :  Memory: 2GB Processor: Intel® Core™2 Duo CPU E7400 @ 2.80GHz × 2  OS Type: 32-bit Disk: 59.3 GB


Common sense says that you don't wave solder batteries, because the wave would short them for seconds. Yet in  I read       Primary lithium cells may be wave soldered as long as the cell temperature does not exceed +85°C. Cells may be placed in a holder or hand soldered after reflow (tabbed cells).     The first sentence seems to suggest that it's OK to wave solder batteries. Do I read this correctly, and doesn't the battery suffer from the shorting?


My  input box must accept the following combination  (123) 123-4567 or 123-123-1234   Can anyone help me out to make regular expression?


Recover a phone number a dialed with no signal

At the bar last night I got a number from an amazing girl that I dialed in the bar. I had no signal when I dialed the number (the bar was deep underground) and I don't see the number in my call history.  How can I recover this number?


Solutions of quadratic equation with complex coefficients, using the quadradic formula.

I have a hard time solving the following equation.  $$z^{2} + (1 - i) \cdot z - i = 0$$  I tried factorization and got $z = -1$ or $z = i$, which I suppose are correct.  However, when I try the quadratic formula for solving second degree equations, the results I get don't match with the solutions I get above.


Turning off or restarting iPhone if lock button is broken?

Now that I know , I was wondering how I can restart the phone or turn it off.  The lock button is completely unresponsive and holding it down does nothing. Are there any workarounds besides replacing the button?


TP-Link MR3220 3g Router not able to ping to its DDNS Address even after disabling SPF security

I have a TP-Link MR3220 3G router. I'm using this router with a 3G USB modem to connect to the Internet.  Unfortunately I cannot ping the modem from outside to its DDNS address, even after disabling all security features like SPF filter etc. Since I cannot access this modem from outside through its DDNS address, I'm not able to use its port forwarding feature for my mail server.   I also noticed that its remote management feature through Web Console wasn't working properly either.  How can I fix this?


MySQL changed my PATH and removed all other items I placed there. Need help reverting back

I installed MySQL some days ago on my Windows machine. Today I noticed that it modified my PATH to just:  C:\Program Files\MySQL\MySQL Shell 8.0\bin\  I had a lot of other items added to my PATH over the course of time and I lost all that. Is there any way I could revert back?


AMD-Action:downloadProduct:SP error on clean install

I'm getting the AMD-Action:downloadProduct:SP error when trying to reinstall macOS, it doesn't even get to the option to sign in with an apple ID.  I've tried the solutions below but it's still not working:      I've also tried creating a bootable usb using transmac starting by making a GPT partition but it doesn't get discovered as a boot device.  iMac Late 2013


How do you install an HP Envy 4250 printer with the Ubuntu operating system?

How do you install the HP Envy 4520 printer using the Ubuntu operating system? When we tried to install the printer it said it did not recognize our operating system which in Ubuntu.


I need to make my input field excepts 16 digits, and 20 chars. The digits are 1-9. And chars are only  ().   So, braces and dots. I can make those braces and dots into my regex to work.  $('#telephone').on('keypress', function (event) {     var regex = new RegExp("^[0-9]+$");      var key = String.fromCharCode(!event.charCode ? event.which : event.charCode);     if (!regex.test(key)) {       event.preventDefault();       return false;     }   });   For example I tried:  var regex = /^[().]{20}[0-9]{16}$/;   And so on, but I guess I am missing a bigger picture. Thank you for your help.  The enterd data should look something like this:  33363748574635274()()....()()()..   And so on. No matter where is dot placed and where is brace placed.


How to capture a still image from digital video?

I'd like to get a still image from a digital video I've taken.  A quick search has revealed these two possibilities,     which uses vlc player  which uses Imagegrab   Any suggestions on which might be better or alternatives?    I'd be using Windows OS  Update In the end I used Windows Live Movie Maker


Late running Eurostar service from Brussels

What happens if my Eurostar service from Brussels is running late and I miss my Grand Central train from Kings Cross


It's possible to imagine something, for example a table, we see one everyday and can bring it in front of our minds eye (although it's a moot point whether we can see it - I certainly don't). But of course this is a real object so we have a referent. But we need not have a referent: to imagine a unicorn means we are hybridising our referents.   But to imagine nothing in its proper sense (ie not the lack of something or just space) seems impossible to me, we cannot avoid our sense of ourselves.


"English", "the English" or "an English"?

Well, one thing came in my mind when I've posted a comment on SO.  Comment is: Do you understand English?  Can we write the English or an English ?  I'm generally use  when i confuse, but when i pasted this three different sentences, it shows: No grammar or spelling mistakes found  So, which one is right, and grammatically correct?


I am a high school student studying about gravitational waves. I hope they are similar to other waves like sound waves, etc. So I what to know exactly what oscillates in a gravitational wave. Like in sound waves, density of a medium oscillates over its maximum and minimum value. I wonder what could be oscillating?


The help pages in R assume I know what those numbers mean, but I don't. I'm trying to really intuitively understand every number here. I will just post the output and comment on what I found out. There might (will) be mistakes, as I'll just write what I assume. Mainly I'd like to know what the t-value in the coefficients mean, and why they print the residual standard error.   Call: lm(formula = iris$Sepal.Width ~ iris$Petal.Width)  Residuals:      Min       1Q   Median       3Q      Max  -1.09907 -0.23626 -0.01064  0.23345  1.17532    This is a 5-point-summary of the residuals (their mean is always 0, right?). The numbers can be used (I'm guessing here) to quickly see if there are any big outliers. Also you can already see it here if the residuals are far from normally distributed (they should be normally distributed).  Coefficients:                  Estimate Std. Error t value Pr(>|t|)     (Intercept)       3.30843    0.06210  53.278  < 2e-16 *** iris$Petal.Width -0.20936    0.04374  -4.786 4.07e-06 *** --- Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1    Estimates $\hat{\beta_i}$, computed by least squares regression. Also, the standard error is $\sigma_{\beta_i}$. I'd like to know how this is calculated.  I have no idea where the t-value and the corresponding p-value come from. I know $\hat{\beta}$ should be normal distributed, but how is the t-value calculated?  Residual standard error: 0.407 on 148 degrees of freedom   $\sqrt{ \frac{1}{n-p} \epsilon^T\epsilon }$, I guess. But why do we calculate that, and what does it tell us?  Multiple R-squared: 0.134,  Adjusted R-squared: 0.1282    $ R^2 = \frac{s_\hat{y}^2}{s_y^2} $, which is $ \frac{\sum_{i=1}^n (\hat{y_i}-\bar{y})^2}{\sum_{i=1}^n (y_i-\bar{y})^2} $. The ratio is close to 1 if the points lie on a straight line, and 0 if they are random.  What is the adjusted R-squared?  F-statistic: 22.91 on 1 and 148 DF,  p-value: 4.073e-06    F and p for the whole model, not only for single $\beta_i$s as previous. The F value is $ \frac{s^2_{\hat{y}}}{\sum\epsilon_i} $. The bigger it grows, the more unlikely it is that the $\beta$'s do not have any effect at all.


So in Euler's solution of the Basel problem he takes  $\sin x= x\left(1-\frac{x^2}{\pi^2}\right)\left(1-\frac{x^2}{4\pi^2}\right)\cdots$  well, i was playing around with it and put $ x=\frac{\pi}{2}$  After manipulating quite a bit, $$\frac{2}{\pi}=\left(1-\frac{1}{2^2}\right)\left(1-\frac{1}{(2*2)^2}\right)\cdots\left(1-\frac{1}{(2n)^2}\right)\cdots$$ after simplifying a bit$$\frac{2}{\pi}=\left(\frac{3}{4}\right)\left(\frac{15}{16}\right)\left(\frac{35}{36}\right)\left(\frac{99}{100}\right)\cdots$$  I tried evaluating LHS by hand, and the partial products slowly do decrease towards RHS, and we know that they will not decrease forever because $$\lim_{n\to\infty} \frac{n^2-1}{n^2}=1$$ so can anyone help by writing a program which can do partial sum up to high values of n and tell me if its true. PS.I am in 10th standard do if im wrong anywhere please dont explain in too complicated mathematics. thanks


Does light or observation collapse wave functions?

I hear that observation is what causes the wave function collapse, but that doesn't make sense considering that an eye or camera is just a physical system with no particularly special properties. In explanations it say that light causes the collapse if that's the case why do you need an observer? If you shined a light while not in the room of the double silt experiment would it still act as a particle?


When I import a specific function from a module, that also has code in it apart from that function, it runs the entire module

I'm trying to learn python and I've tried really hard but for some reason I can't figure this out.   This is the module, named user_profile, where the function that I want to import comes from:  def build_profile(first, last, **user_info):     profile = {}     profile['first name'] = first     profile['last name'] = last     for key, value in user_info.items():         profile[key] = value     return profile  user_profile = build_profile('john', 'smith',                              city = 'new york',                              occupation = 'banker',                              girlfriend = 'janice')  for key, value in user_profile.items():     print(key.title() + ": " + value.title())   Now I want to import build_profile into another module like so:  from user_profile import build_profile   I just want build_profile to be imported, but for some reason it runs user_profile entirely. What's going on?


Why is it so difficult to find beginner books in Algebraic Geometry?

I don't understand why it is so difficult to find a really beginner book in Algebraic Geometry. Let's take for example . I've already heard on MSE and some students of my university saying that it's very concise and leave the proofs as exercises to the students, which personally I agree with. The last thing I've heard about this book is from a professor of my university (he is a little bit old now, but he was a very prolific researcher in Algebraic Geometry), he said that Chapter 7 is very hard to understand and has a lot of hard calculations and he never fully understood this chapter.  There are other introduction books, but they are very few and miss some things that a good introduction book should have.  I think this doesn't happen in Analysis and Abstract Algebra, for example. There are a lot of good introduction books with very detailed proofs, solutions to exercises and so on. I can't imagine a very good researcher in Analysis saying "I've never understood this chapter about continuity of the introductory book of the author $X$".  Why does this happen with Algebraic Geometry?  Is it maybe because this area is very recent? Or because there aren't many buyers to buy Algebraic Geometry books? Or because this area is indeed very hard to understand (and it will never have a good beginner book).   Thanks!


Why does "the probability of a random natural number being prime" make no sense?

I read an essay about prime numbers. In it the author suggests that a natural first question to ask is,      What is the probability of a random natural number being prime?   but proceeds to dismiss it as "not making sense". I wonder what's wrong with the question. Is its meaninglessness related to the fact that there is an infinite number of naturals?


The largest integer that divides $p^4-1$, in which p is a prime greater than $5$

The question is to find the largest integer that divides all $p^4-1$, where p is a prime greater than 5. Being asked this question, I just assume this number exists. Set $p = 7$, then $p^4-1=2400$. I don't have any background in number theory and not sure what to do next. Thank you for your help!


Getting different results using Select by Location with ArcPy vs ArcMap?

I have two different layers. One layer contains features that are supposed to sit directly on top of features in the other layer.  With ArcPy I'm doing a SelectLayerByLocation with "ARE_IDENTICAL_TO" and then a "SWITCH_SELECTION" in order to find which features from layer one aren't directly on top of layer two, and then updating the geometry accordingly.  However, ArcPy is giving me different (incorrect) results than using the Select by Location in ArcMap.  Granted the feature is only 0.01 ft away from the other, but it's still not identical.    When using ArcPy, the feature above with the S is selected, but when I use Select by Location in ArcMap it's not.  layer1_fl = arcpy.MakeFeatureLayer_management(layer1, layer1 + "_fl") layer2_fl = arcpy.MakeFeatureLayer_management(layer2, layer2 + "_fl")  arcpy.SelectLayerByLocation_management(layer1_fl, "ARE_IDENTICAL_TO", layer2_fl)   Any idea why it's acting this way?    As suggested by @FelixIP  I added arcpy.env.outputCoordinateSystem = arcpy.SpatialReference(102726) and all worked as expected.


How can I add an ampersand for a value in a ASP.net/C# app config file value

I've got a C# program with values in a config file.  What I want is to store ampersands for an url value like...  <appSettings>   <add key="myurl" value="http://www.myurl.com?&cid=&sid="/> </appSettings>   But I get errors building my site.  The ampersand is not allowed.  I've tried various forms of escaping the ampersands to no avail.  Anyone know of the correct form to do this?  All suggestions are welcome.


Book with astronaut returning to an empty Earth

I am trying to remember the title of one of my favour science fiction books from the 1990s. It began with an astronaut sent to the stars returning decades later to an Earth empty of people. He finds a computer terminal and gradually dormant dopiter systems wake up and start to find out what happens.  Initially the only working computer function is a story telling module which starts trying to explain what happens. The story moves back in time as the computers search records and focus on a character called (from memory) Peter Devos or similar who starts to dream about a frozen girl on a spaceship. The story is complex and I really want to read it again.


Fastest way to clamp a real (fixed/floating point) value?

Is there a more efficient way to clamp real numbers than using if statements or ternary operators? I want to do this both for doubles and for a 32-bit fixpoint implementation (16.16). I'm not asking for code that can handle both cases; they will be handled in separate functions.  Obviously, I can do something like:  double clampedA; double a = calculate(); clampedA = a > MY_MAX ? MY_MAX : a; clampedA = a < MY_MIN ? MY_MIN : a;   or  double a = calculate(); double clampedA = a; if(clampedA > MY_MAX)     clampedA = MY_MAX; else if(clampedA < MY_MIN)     clampedA = MY_MIN;   The fixpoint version would use functions/macros for comparisons.  This is done in a performance-critical part of the code, so I'm looking for an as efficient way to do it as possible (which I suspect would involve bit-manipulation)   EDIT: It has to be standard/portable C, platform-specific functionality is not of any interest here. Also, MY_MIN and MY_MAX are the same type as the value I want clamped (doubles in the examples above).


If $f$ is continuous on $[0,1]$, prove that $\lim_{n\to\infty}\int_0^1f(x^n)\,dx=f(0)$

$\textbf{The Problem:}$ Prove that if $f$ is continuous on $[0,1]$, then   $$\lim_{n\to\infty}\int_0^1f(x^n)\,dx=f(0).$$   Note: Here we are using the Riemann integral.   $\textbf{My Thoughts and Attempt:}$ Choose $0<\delta<1$. Since $f$ is continuous on a compact interval, it follows that it is also uniformly continuous, on $[0,1]$ and hence, on $[0,\delta]$. Thus,  $f(x^n)\to f(0)$ uniformly on $[0,\delta]$. Therefore, $$\lim_{n\to\infty}\int_0^\delta f(x^n)\,dx=f(0)\cdot\delta.$$ Since $0<\delta<1$ was arbitrary, it follows that $$\lim_{n\to\infty}\int_0^1f(x^n)\,dx=f(0).$$    $\textbf{My Concerns:}$ I am not entirely convinced that I have executed my $\delta$ trick, which turns the problem into a double limit, correctly. Could anyone please provide some feedback on my proof above and whether the introduction of $\delta$ is handled appropriately?  Thank you for your time and appreciate any feedback.


packing up an entire directory structure ignoring a certain filetype

I want to create a tarball of a directory structure.  I know I can pack the entire directory by executing tar czvf testdir or all the files in it with tar czvf testdir/*.  But what I want to do is exclude all files of a certain extension that occur anywhere in the directory.  For example I want to pack up all files in the same directory structure, but leave out all .pyc files.  Is this possible?


I have one HP server Proliant ML 350 G5 with raid controller E200i. Diagnostic system shows the message (after system crash and reboot):  Malformed NVRAM detected. Device: HP Smart Array Controller, Slot 0 Property name: World Wide ID  I am confused about NVRAM: is it relate at memory RAM for BBWC, added as optional for better performance, or it is a memory internal controller RAID?  thank you,  Max


So here's my problem: I am trying to use \cite{} in a beamer. I would like the output of \cite{{AB_00} to be either something like [1] or Author A \& Author B, which is essentially what I've written in brackets. Below is my code and its output:  \documentclass[10pt]{beamer} \mode<beamer>{\usetheme[hideothersubsections, right, width=22mm]{Goettingen}}  \usepackage[english]{babel} \usepackage{biblatex}   \begin{document} \begin{frame} Test \cite{AB_00} \end{frame}  \begin{frame} \begin{thebibliography}{} \bibitem[Author A \& Author B]{AB_00} A \& B 2000 \end{thebibliography}{} \end{frame} \end{document}     Any help or suggestion is greatly appreciated.  P.S. I've tried turning my code into a m.w.e. If however something is unclear, please let me know so I can try clearing it up.


Why do we feel cold when we switch on the fan?

We know that on increasing the kinetic energy of a gas its temperature increases: $$\text{Kinetic Energy} = \frac32 kT$$ where $k$ is the Boltzmann constant. This equation is derived from the .   When we switch on a fan we increase the kinetic energy of the gas molecules increasing their temperature, but we generally feel cold. This happens even if we are not sweating. What am I missing here?


Importance of the homogeneity assumption in definition of linear map

Let $V$ and $W$ be vector spaces over field $F$.  A function $f: V \rightarrow W$ is said to be linear if for any two vectors $x$ and $y$ in $V$ and any scalar $\alpha\in F$, the following two conditions are satisfied:   $f(x + y) = f(x) + f(y)$ $f(\alpha x) = \alpha f(x)$   Let $F$ be a field of real numbers. Is it possible to construct $f$ such that the first condition is satified but not the second one?


How to download 32 bit ubuntu on a 64 bit machine?

My laptop is a 64 bit machine, but I need to download a 32 bit version of the Ubuntu OS because my school has said that a particular program I need 'was made with the intention that the user will not be running it on a 64 bit version of the Ubuntu OS'. That is pretty much true because I have tried many ways to run it, and all my attempts have failed.  The problem is that after I have downloaded the client for the 32 bit version of Ubuntu (I'm sure it's the client for 32 bit because I have even redownloaded it) and installed it into my computer, the system settings in Ubuntu will say that I have the 64 bit of the OS installed. I check this by going to system settings > Details > OS type. My question is... how do I install a 32 bit version of the Ubuntu OS on a 64 bit window 7 machine?


How can you change Windows 10 keyboard shortcuts?

I have several apps that I use with keyboard shortcuts that I'm used to and the new shortcuts built into Windows 10 have taken some of them over. These are already ingrained habits and I don't want to change nor do I care too much about what the new shortcuts do.  So, is there a way to override Windows's keyboard shortcuts, at least for the new shortcuts in Windows 10?  Search the interwebs and my windows settings has not yielded anything yet.  Thanks!


How to evaluate the following integral: $\int_0^1\frac{\log(1+x)}{1+x^2}dx$

I would like to evaluate: $$\displaystyle\int_0^1 \frac{\log(1+x)}{1+x^2}\, dx$$  I have tried to evaluate this using integration by parts but failed. How can I evaluate it?


Prove that the number of $\alpha\in\mathbb{F}_{27}$ such that $|A_\alpha|=26 $ equals 12.

Let $\mathbb{F}_{27}$ denote the finite field of size 27. For each $\alpha\in\mathbb{F}_{27}$ , define $ A_{\alpha}$ $=$ { $ 1, 1+\alpha , 1+\alpha+{\alpha}^2 , 1+\alpha+{\alpha}^2+{\alpha}^3 , .... $} . Then  prove that  the number of  $\alpha\in\mathbb{F}_{27}$ such that $|A_\alpha|$=26 equals 12.  $ 0\in A_\alpha $ if and only if $\alpha\neq 0$ For the first proof , the multiplicative group of the field $\mathbb{F}_{27}$ is cyclic and its order is 26  , so there are 12 generators in that group.   Now  I need  to  show  that  $ 1+\alpha+{\alpha}^2+.. {\alpha}^{25} $ =0  , where order of $\alpha$=26 . Since   $\alpha ^{26}$ =1 ($\alpha$-1)(1+$\alpha$+${\alpha}^2$+...+${\alpha}^{25}$)=0 , since $\alpha\neq 1$  , So $ 1+\alpha+...+{\alpha}^{25} $ =0 My question is , can I write these last two  lines?  I mean are those two lines alright to write? If those two lines are invalid then I need some help to show  $ 1+\alpha+{\alpha}^2+..+{\alpha}^{25} $=0  .Thanks


Adding A responsive Footer to a website. Footer is on master page and should be shown on every content page

How To Add Footer in asp.net Which adjusts automatically with content on the page and the screen size.  I have a Footer on a master page. and I want all the content pages should adapt automatically to the content on the screen or screen size  I have tried.  footer {         background-color: lightgray;         position: unset;         left: 0;         margin-bottom: auto;         height: 64px;         width: 100%;         overflow: hidden;     }   the added footer on the master page  <footer>         <asp:Image ID="Image2" runat="server" ImageUrl="~/wp-content/Images/114x114.png" ImageAlign="Baseline"             AlternateText="Foodora.com" Height="67px" />         &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;                 <asp:Image ID="Image3" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/facebook_sq.png" />         &nbsp;&nbsp;&nbsp;             <asp:Image ID="Image4" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/twitter_sq.png" />         &nbsp;&nbsp;&nbsp;             <asp:Image ID="Image5" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/instagram_sq.png" />     </footer>   but on the page, that has a small amount of content the footer has white blank space ...


How to disable auto sleep in Ubuntu 18.04

I recently installed Ubuntu 18.04 in a rather old laptop I have, and am having some major issues with the device going to sleep and then getting stuck in a loop where it goes to sleep every five seconds once woken up. It is a Lenovo G555-0873, and if it works great and fine when coming up after a fresh reboot, but if it ever sleeps, then it gets stuck constantly trying to sleep and is incredibly difficult to troubleshoot because I have to complete every interaction in the ~5 seconds I have before it sleeps again. I've tried disabling it from going to sleep at all by changing the following settings:  In Privacy, I've turned off Screen Lock.  In Power, I've turned off "Dim screen while inactive", set "Blank screen" to never, and turned off "Automatic suspend"  I can't find any other settings that seem like they would effect this sort of thing. Per an old thread on a similar issue, I've also run the following command:  xset -dpms   None of this has seemingly had any effect. The laptop still goes to sleep when left idle, and then proceeds to enter it's strange sleep-loop when brought back up, and loops like that until eventually rebooted. Any assistance or suggestions are appreciated.  Edit: I've determined now that it only happens when the lid of the laptop is shut. If I leave it with the lid open and the laptop idle it never goes to sleep, but it still sleeps instantly once I shut the lid (and then begins the hell of sleep-looping after waking up).


Problem setting shortcut for Tor Browser

I've installed Tor Browser and I can run it buy the command:  ./start-tor-browser.desktop    This command works as long as the Tor icon(the globe icon) is in : /home/user/tor-browser_de/ and I am also there in  ~/tor-browser_de.  When I want to set the shortcut Super+T, I use the command ./start-tor-browser.desktop, but it does not work. I copied the Tor icon to /home/user, but the problem still persists. How can I fix this problem?


Calculate $$\lim_{x\to 0}\dfrac{1}{x^{\sin(x)}}$$  I'm pretty much clueless here, only that there is L'hospital obviously here.   Would appreciate any help.


Save each sheet in a workbook to separate CSV files

How do I save each sheet in an Excel workbook to separate CSV files with a macro?  I have an excel with multiple sheets and I was looking for a macro that will save each sheet to a separate CSV (comma separated file). Excel will not allow you to save all sheets to different CSV files.


I am trying to geometrically understand how a degenerate conic of a parabola can form a two parallel lines since I read  that such a conic is a line or two parallel lines. Can anyone explain how an intersection of a plane and a double cone can form parallel lines?


Digitizing Airport approach-zone with z information in QGIS?

I'm trying to create a vector layer in QGIS out of this Z-dimensioned approach-zone for an ongoing multi-criteria analysis:   * The oval shaped base should be 59,56 meters high (Z)   For every "ring" z-value should be increased by 10 meters, ending at 159,56 meters (Z) The cone shaped things are flat plane 163/164 meters up until the 130 meter mark, then drops until it reaches 59.56.   Could anyone with more experience with QGIS-digitizing with z-values point out a direction?   What painting tools to use? Right now I'm manually painting them, but results looks horrible and edgy.   note: I've already geo-referenced the above image.


Jquery checkbox event handling not working after ajax call

I have ajax call to get data from database and show the table row after success response. Inside the table row I have checkbox on it. I want to get selected index after the checkbox checked. I faces some problem when I set event handling to get selected index. This is my scripts.     I don't have problem with the ajax, my problem just inside second script to get the selected index. The script seems not working without any error. Please anyone help me to solve this problem. Thanks.


Can I travel to Australia as a tourist on a business visitor visa?

I currently hold a multiple-entry business visitor (subclass 600) visa for Australia valid until January 2020, and I have traveled to Sydney multiple times before for business.   I am planning to spend my next holiday (i.e., next month) in other parts of Australia (Queensland & Victoria). For this purpose, do I need to apply for a tourist visa or will my business visitor visa work?  Note: I have already looked at a similar query raised here but there was no definite answer to it.      Edit: My plan to visit Australia last year was canceled but in May 2018, I went there as a tourist on my business visa and didn't face any issue with immigration.


$x-\frac{x^2}{2}+\frac{x^3}{3(1+x)}<\log(1+x)<x-\frac{x^2}{2}+\frac{x^3}{3}$, $x>0$  Here I can only see that the right side of second inequality i.e. $x-\frac{x^2}{2}+\frac{x^3}{3}$ comes in the expansion of $\log(1+x)$.  We have done the Lagrange's mean value theorem and intermediate value theorem, do these have anything to do with the inequality.  Kindly provide some hint.


How to send PHP $_GET variable with $_POST method when using it in SQL INSERT query?

I have a (subject) and (page) TABLES in a database.  page TABLE belongs to subject TABLE, each subject has an ID  When user click on a subject mysite/blog?subject=(ID gets set__) 1,2,3,4,5  So i want pages to be INSERTED according to in which subject they are in URL.  Well, i'm sending data using POST form to a (form_process.php) page.  <?php             if(isset($_POST["submit"])){          $Message = $_POST["Content"];           $query  = "INSERT INTO page ";          $query .= "(Message, SubjectID) ";          $query .= "VALUES ('{$Message}', $_GET['subject'])";          $result = mysqli_query($connection, $query);           if(mysqli_affected_rows($connection) > 0){            echo "Page added to its beloging subject";          }      } ?>   I get this error:       Notice: Undefined index: subject in   C:\xampp\htdocs\kerimgrozny\public\blog.php on line 64   The problem is: when using $_GET variable in INSERT query as FOREIGN KEY, It gets undefined.  The link on GitHub:


Just like we get to mark questions as favorites, is there any scope/relevance of being able to mark individual answers as favorites as well. Of course, there is an indirect way to do that by 'upvoting' the answer and it will be recorded in the user profile's upvotes. But if we can mark favorite answers, it helps coming back later and referring to the concept (which supposedly has been explained in the answer).


The mounted combatant feat (PHB 168) allows someone to "force an attack targeted at your mount to target you instead." Suppose I am playing on a grid. Let E be enemies without reach/ranged weapons. M be the spaces a large mount occupies. And R be the space I occupy while riding the mount.  \$\begin{array}{|l|l|r|} \hline \text{E} & \\ \hline \text{E} & \text{M} & \text{R}\\ \hline \text{E} & \text{M} & \text{M} \\ \hline \end{array} \$  What happens when I redirect an attack with mounted combatant but I am outside the reach of their weapon on a grid?


Can anyone think of any situation to use multiple inheritance? Every case I can think of can be solved by the method operator   AnotherClass() { return this->something.anotherClass; }


Is it right to say that the charge density of a point charge is infinity? if I were to take a uniformly charged ball with radius R and take the limit $R\to 0$, won't I get an infinite charge density at the origin because there will be a finite charge divided by a volume which goes to 0?  I know you can use the delta dirac function to describe such situations, but I'm not there yet. Generally, is it true to say the charge density of a point charge is 0 everywhere and infinite at the origin?


Did Martin Scorsese use "whom" properly in this interview?

I was reading an interview with Martin Scorsese in the Times and he said the following:     But, no matter whom you make your movie with, the fact is that the screens in most multiplexes are crowded with franchise pictures.      Is this proper usage? I have always heard you use "whom" when "who" would be the object of the sentence, or more colloquially when it would make sense to say "him/her" instead of "he/she". In this example, if we replace "whom" with "him" the word order doesn't make sense, so I can't figure it out. I think the larger problem is he ended the clause with a preposition, and the correct verbiage is      It doesn't matter with whom you make your movie   but that doesn't sound as good.


Can I caulk over cracked grout (shower floor) as a temporary fix?

We have an older shower, with 1x1 tiles on the floor. Some of these, the grout has started to crack, and we want to prevent water damage. However, we've exhausted our renovation budget for the year, and won't be able to do a shower replacement until sometime late next year.  As a temporary hack, could we apply a thin layer of caulk to these grout lines? Would this help?


I get that it wouldn't have happened in 1999, but what about 2004, 2009, 2014, or even in 2019. There seems like there isn't any danger, so did they bring it back and if they didn't, why not?


I wanted to align a set of equations to left. I found on the Internet that you can do it easily with align* environment.   I found it here:   So I did it:  \begin{align*}  f(b)-f(a)=&f((b_1,b_2,\dots,b_k))-f((a_1,a_2,\dots,a_k))=\ &=\sum_{i=1}^{k}[f((a_1,\dots,a_{i-1},b_i,\dots, b_k))-f((a_1,\dots,a_i,b_{i+1},\dots, b_k))  \end{align*}   Unfortunately, I got bunch of red errors saying that there are missing $s. Why? Doesn't that align* environment provide a math environment already?


How to Remove virus completely from laptop

I recently tried to download some files from net without antivirus.Ever since I am having red traces all over my screen.Then I installed avast free version and run full scan but no improvement.Then I started my laptop in safe mode and started malware antimalware with full system scan.But it didn't remove.Please give me some suggestions so I can recover from this situation.


I am getting this error when I try to run this query. I am drawing a blank on why this is happening. Everything else is running correctly. Any help or advice would be appreciated.      COUNT(Allergies_Types__c) childDairy FROM Child_Consent_Form__c                                              ^ ERROR at Row:9:Column:75 Didn't understand relationship 'Child_Consent_Form__c' in FROM part of   query call. If you are attempting to use a custom relationship, be   sure to append the '__r' after the custom relationship name. Please   reference your WSDL or the describe call for the appropriate names.                SELECT                      puLocation__r.Name LocationName,                      puLocation__r.notes__c LocationNotes,                     puLocation__r.Milk_Location__c MilkLocation,                     puLocation__r.Location_type__c LocationType,                     Child_Consent_Form__c.Active_Inactive__c,                     count(ID) numberofchildren,                     count(Allergies__c) childrenwithalergies,                     (SELECT COUNT(Allergies_Types__c) childDairy FROM Child_Consent_Form__c                         WHERE Allergies_Types__c INCLUDES ('Dairy-free'))              FROM Child_Consent_Form__c               WHERE     Child_Consent_Form__c.Active_Inactive__c = 'Active'              GROUP BY puLocation__r.Name,                        puLocation__r.notes__c,                       puLocation__r.Milk_Location__c,                       puLocation__r.Location_type__c,                       Child_Consent_Form__c.Active_Inactive__c


Let $G=S_4, N=\{e;(1,2)(3,4);(1,3)(2,4);(1,4)(2,3)\}$   I need to prove that $N\lhd G$  Attempt:  $N\lhd G \iff gng^{-1}\in N$   and it is in $N$ for all $g\in G, n\in N$


I am currently making a mod for Minecraft but I have come to a stop because I am lacking in some knowledge. I need to get data for the entity I am looking at, which I believe requires the use vectors, something I don't really know how to use.   How would I achieve this? Some stuff that I think could help are mc.thePlayer.getLookVector() which returns the normalized vector of the user and mc.theWorld.loadedEntityList, which  is a List with all the loaded currently loaded entities.


Two users, one for SO, one for other sites

I have two users on SE. Both of them are registered in SO, and one of them is tied to other SE communities accounts like Arqade, ELL, etc. How can I sign into SO with one account while signing into other communities with another account? When I log out from one account from one community it seems I'm log out from all communities.


Kali Linux not booting after update [bricked]

After not using kali for a long time (+/- 2 years) I decided to run it again. First thing I did was opening my terminal and updating kali using apt-get update && apt-get upgrade. To my surprise it couldn't find any update. I checked my sources.list and found several lines, which I can't remember anymore. Deleted and replaced them with "deb  kali-rolling main non-free contrib" according to the official website. Opened the terminal again and entered the update command. It found a ton of updates, dpkg'd most of them and after half an hour updating was completed.   Rebooted my pc and encountered the following on boot up:   Got the same result when trying to open recovery mode.  What is the reason behind my bricked kali and how do I resolve my problem?


How to avoid perceived circularity when defining a formal language?

Suppose we want to define a first-order language to do set theory (so we can formalize mathematics). One such construction can be found . What makes me uneasy about this definition is that words such as "set", "countable", "function", and "number" are used in somewhat non-trivial manners. For instance, behind the word "countable" rests an immense amount of mathematical knowledge: one needs the notion of a bijection, which requires functions and sets. One also needs the set of natural numbers (or something with equal cardinality), in order to say that countable sets have a bijection with the set of natural numbers.  Also, in set theory one uses the relation of belonging "$\in$". But relation seems to require the notion an ordered pair, which requires sets, whose properties are described using belonging...  I found the following in Kevin Klement's,  (pages 2-3).  "You have to use logic to study logic. There’s no getting away from it. However, I’m not going to bother stating all the logical rules that are valid in the metalanguage, since I’d need to do that in the metametalanguage, and that would just get me started on an infinite regress. The rule of thumb is: if it’s OK in the object language, it’s OK in the metalanguage too."  So it seems that, if one proves a fact about the object language, then one can also use it in the metalanguage. In the case of set theory, one may not start out knowing what sets really are, but after one proves some fact about them (e.g., that there are uncountable sets) then one implicitly "adds" this fact also to the metalanguage.  This seems like cheating: one is using the object language to conduct proofs regarding the metalanguage, when it should strictly be the other way round.  To give an example of avoiding circularity, consider the definition of the integers. We can define a binary relation $R\subseteq(\mathbf{N}\times\mathbf{N})\times(\mathbf{N}\times\mathbf{N})$, where for any $a,b,c,d\in\mathbf{N}$, $((a,b),(c,d))\in R$ iff $a+d=b+c$, and then defining $\mathbf{Z}:= \{[(a,b)]:a,b\in\mathbf{N}\}$, where $[a,b]=\{x\in \mathbf{N}\times\mathbf{N}: xR(a,b)\}$, as in  question or  on Wikipedia. In this definition if set theory and natural numbers are assumed, then there is no circularity because one did not depend on the notion of "subtraction" in defining the integers.  So my question is:     Question Is the definition of first-order logic circular?   If not, please explain why.   If the definitions are circular, is there an alternative definition which avoids the circularity?   Some thoughts:   Perhaps there is the distinction between what sets are (anything that obeys the axioms) and how sets are expressed (using a formal language). In other words, the notion of a set may not be circular, but to talk of sets using a formal language requires the notion of a set in a metalanguage. In foundational mathematics there also seems to be the idea of first defining something, and then coming back with better machinery to analyse that thing. For instance, one can define the natural numbers using the Peano axioms, then later come back to say that all structures satisfying the axioms are isomorphic. (I don't know any algebra, but that seems right.) Maybe sets, functions, etc., are too basic? Is it possible to avoid these terms when defining a formal language?


I'm trying to connect to my newly purchased website on GoDaddy via SSH. However, when I try to connect from my Mac, I get the following error message:  $ssh username@website.com -v -v -v OpenSSH_5.9p1, OpenSSL 0.9.8zg 14 July 2015 debug1: Reading configuration data /etc/ssh_config debug1: /etc/ssh_config line 20: Applying options for * debug2: ssh_connect: needpriv 0 debug1: Connecting to website.com [XXX.XXX.XXX.XXX] port 22. debug1: Connection established. debug1: identity file /Users/UserName/.ssh/id_rsa type -1 debug1: identity file /Users/UserName/.ssh/id_rsa-cert type -1 debug1: identity file /Users/UserName/.ssh/id_dsa type -1 debug1: identity file /Users/UserName/.ssh/id_dsa-cert type -1 ssh_exchange_identification: Connection closed by remote host   When I initially tried connecting, I was prompted for a password. I entered my password, although it was apparently incorrect. After a few attempts, it stopped asking me for my password and started giving me the above message instead.   has a very similar error message, although it's missing the debug2: ssh_connect: needpriv 0 line. I tried the answers, although they did not fix my problem.


dpkg exit with error "cannot scan updates directory `/var/lib/dpkg/updates/': No such file or directory", how to fix it?

Earlier, I had a problem with a package, and I (wrongly) ran this:  rm -r /var/lib/dpkg/*   See also .  Now when I try to upgrade, I get this:  E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it? masoud@masoud-PC:~$ sudo apt-get upgrade  E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?   and when I use: sudo dpkg --configure -a   I get this:  dpkg: error: cannot scan updates directory `/var/lib/dpkg/updates/': No such file or directory     and for sudo apt-get upgrade -f get:  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... failed. The following packages have unmet dependencies:  ia32-libs : Depends: ia32-libs-multiarch but it is not installable  wine1.4 : Depends: wine1.4-i386 (= 1.4.1-0ubuntu5) but it is not installable E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages. E: Unable to correct dependencies


Is this a superficial Loss? Stock Sale and Put Option

I sold 250 shares of a stock at a loss of (-1,000). 2 weeks later bought a single put contract (100 shares) n the same stock. If I sell the put option for profit a few days later, is this a partial superficial Loss (wash sale)? If so, how do I calculate it? (CRA, Canada)


How to write global keyboard hook in Ubuntu (Linux) (like Hook for Windows)  In C/C++ or Python


Are there any advantages to using zsh vs bash shell in Terminal app? Also, can you use zsh from the terminal? My understanding of zsh is skewed.


VERIFYING: Proving an $n \times n$ Matrix Vector Space

Let $V$ be the vector space made by the $n \times n$ square matrices.  a) Prove that $S=\{A\in V|A^t=A\}$ is a subspace of $V$  b) Prove that $T=\{A\in V|A^t=-A\}$ is a subspace of $V$  c) Prove that $V=S\oplus T$    SOLUTION  a) Let $O$ be the zero matrix, then $O \in S$ because $O^t=O$.  Then, let $A, B \in S$; and $r, k \in \mathbb R$. Hence  $$rA+kB=r(A^t)+k(B^t)=rA^t+kB^t$$ then $rA+kB \in S \implies$ $S$ is a subspace of $V$  b) Let $O$ be the zero matrix, then $O \in T$ because $O^t=O$.  Then, let $A, B \in T$; and $r, k \in \mathbb R$. Hence  $$rA+kB=r(-A^t)+k(-B^t)=-rA^t-kB^t=-(rA^t+kB^t)$$ then $rA+kB \in T \implies$ $T$ is a subspace of $V$  c) I have no idea how to do it.  I HOPE YOU CAN HELP ME VERYFING THE a), b) parts and with the part c).


What does "Normal Distribution is conjugate to Normal" mean?

I kind of understand the meaning of conjugate to something but can't really get the clear picture of the concept. Some video lectures on youtube talk about it but they all seem to just say "Normal Distribution is conjugate to Normal" but for me to understand, it wasn't enough to get it. Hope to hear with least mathematical terms.


how to load rtl.css file before style.css

we all know that some languages have right to left "rtl" direction and we can add rtl.css file to modify theme layout in one of the languages that uses RTL direction.  the problem here is that, when i try to make changes to rtl.css file it does not take any effect, and that is because the theme load style.css file first which override my changes.  ex: in rtl.css i added: float: right;  in style.css i added: float: left;  for the same element... the theme loads style.css file first and override "float: right;" even in rtl languages.  i want to load rtl.css first in rtl languages.  thanks.


Are there online resources for finding information on M.S. programs that fit my criteria, without having to go through every school's website?

I'm looking for an M.S. in Computer Science and I found it difficult to properly navigate all the available degrees. I'm interested in a particular focus (computer graphics, not modelling and that kind of stuff but how to do use algorithms in order to create graphics). I also have some constraints on language: I currently speak both Dutch and English, so no German or French master's for me.  There are other questions on this site about  and , but I'm mainly looking for quick preselection (like a top 30 of options I have). I'm looking for a overview of courses as it enables quick elimination which if I have to wait for each uni to answer will take quite a long time  Is there any website or other online resource that will allow me to filter all M.S. programs by my requirements (language or country, research focus) and then find out information (such as the list of courses that comprise the degree) about the programs that meet my criteria, all in one place?