How to call a constructor on an already allocated memory?

How can I call a constructor on a memory region that is already allocated?


How widely accepted are Euros in Hungary and how bad is the exchange rate practiced by shops/hotels?

The official currency of Hungary is the Forint but so far everything I have looked for prices online, such as trains, buses and taxis, are quoted in Euros and Forints. Hotel reservation asked that I pay in Euros at the hotel. Considering that I will only spend a few days in Budapest, are Forints necessary? Or can I pay for transport, admissions and food in Euros? In such a case, how is the conversion rate set?


Proving the divergence of $\sum a_n$ with $a_{n}=\frac{1}{n}\left( 1+ \frac{1}{\sqrt{2}}+\cdots+\frac{1}{\sqrt{n}} \right)$

How can we prove formally that the  series $\sum a_{n}$ diverges whose $n^{th}$ term has been provided below:     $$ a_{n}=\frac{1}{n}\left( 1+ \frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+\cdots+\frac{1}{\sqrt{n}} \right),\qquad n\ge1.$$   The sequence converges to zero but I am not sure how book has proved that the series diverges?


Is there any standard notation for specifying dimension of a matrix after the matrix symbol?

I want to explicitly specify dimension of matrices in some expressions, something like   $$\boldsymbol{A}_{m \times n} \boldsymbol{B}_{n \times m} = \boldsymbol{C}_{m \times m} \, .$$  Is there any more or less standard notation for this?    While this notation is generally unambiguous, I think it become ambiguous, for example, in the following case. Suppose that I have some column or row vector which is conjugate transpose of correspondingly row or column vector. If I write it in the following way  $$\boldsymbol{A}_{n \times 1}^{\dagger} \, ,$$ we can have 2 different interpretations:   matrix $\boldsymbol{A}_{n \times 1}$ is $n \times 1$ column vector and by $\boldsymbol{A}_{n \times 1}^{\dagger}$ I'm referring to its conjugate transpose which is $1 \times n$ row vector; matrix $\boldsymbol{A}_{n \times 1}^{\dagger}$ itself is $n \times 1$ column vector which is conjugate transpose of $1 \times n$ row vector $\boldsymbol{A}$.


What does the expression "consecutive days" mean with respect to badges?  Does it mean that you have to revist the site within 24 hours? Or does it allow that you might visit in the morning and the next day just before you finish work — e.g. over 24 hours, but say under 26 hours?


Is defragging relevant to improving disk performance anymore?

Does it stil make much difference, now that we have much faster and larger HDDs? Generally I find if disk performance is getting too slow, it's probably because of too little free space, and the solution is to buy a new HDD.


I am trying to optimize and write the best code possible (as any developer is) and I have been racking my head trying to figure out if this particular method I am writing is bad code. For some reason in my head I find that having multiple return statements are bad as opposed to having just one. Yet I have nothing in solid writing stating this is bad. Please tell me if this is bad code or not  public boolean fooBar(int foo, int bar){    if(foo == 3) {      return true;    }     if(bar == 3) {      return true;    }     System.out.println("foo or bar is not equal to three");    return false; }   I am not looking for simplification, I am just looking for general ideas on if this is bad code or not and if there are performance issues that could arise from doing this.


How intelligent/magical is Hermione's cat?

It tried to attack Peter Pettigrew by sensing "it" as evil. I doubt a real-life cat will try to protect it's owner from a threat he is naive about. What is the extent of its magic (it sensed Peter as more than a rodent) and intelligence (its peristent)?


I've been practicing baking croissants for a couple months now. I'm getting the hang of it (I feel) but I'm missing a crucial step that I cannot master and can't put my finger on how to fix it. I'll share my process below and I'd appreciate advice on the process. I like being an 'exact' (nearly science) cooker, so to understand my process, ingredients and temperatures. Please feel invited to be critical!  Ingredients:   - 300g flour (10.7g protein / 100g),   - 150g french butter  - 150ml/g water  - 10g sugar, 8g salt, 8g dried yeast  Step 1: I mix the dough and kneed it for about 5 minutes. The result:    Step 2 I roll the dough to a (near) rectangle with a thickness as shown by my finger.    Step 3 I place the slab in the fridge for about 40 minutes, after which it emerges quite hard, but still sufficiently foldable. Three-quarters or two-thirds of the slab is coated with the butter (all 150g of the butter)    Step 4: Starting of lamination I fold the dough as such, followed by rolling it out to a thickness of 1 cm again, and then another fold as also shown below:        Step 5 I let the dough rest for 40 minutes in the fridge, and then perform another double fold, followed by 40 minutes, and another fold.  Step 6 I let the dough rest in the fridge overnight, using a partially wet towel, or other semi-air tight cover  Step 7 In the morning (+8 hours), the dough is taken from the fridge and feel fluffy and soft, as expected with a risen dough. I roll it out to a final thickness of 1 cm as shown:  Step 8 I cut triangles using a regular kitchen knife and add the little cut at the long end to start rolling (shown in front):    Step 9 This is what they look like after rolling. I let them rise for another 30 minutes before entering the oven, pre-heated to 230 degrees C, or 450 Fahrenheit. There's also eggwash on top for a nice brown tan.    Step 10 After 20 minutes, they emerge as such:      Examining The taste is great, really. But I'm not content with the structure. It's too bready and I feel croissants should have a web-like structure with very thin layers within.  In particular with the result, I wonder what has happened. What I observe is:   The oven tray is quite wet after the croissants emerge from the oven. Is it the butter that ran out? Why? Even though the top of the croissant has great flaky-ness, the inside feels more like a regular bread but with butter infused into it.


Increasing the maximum amount of open files for libvirt

For an experiment I'm trying to start as many VM's as possible through libvirt, however with a little over 1000 VM's running I get an error saying: "Failed to create pipe: Too many open files". Any idea of how to fix this?   I've set ulimit soft and high limits for all users to 4096, but when checking: /proc/'process pid of the libvirt daemon'/limits it still says the soft limit is 1024 (hard limit has been set to 4096). When checking the ulimit for any user through 'ulimit -Sn' or 'ulimit -Hn' the limits seems to be set as intended.  This is happening on Ubuntu 12.04 Server, using libvirtd 0.9.8


I am working through the proof for partitioning sum of squares. Could someone please explicitly explain how one goes from line 14 to 15 in the following PDF:     That is, how one moves between these lines -   \begin{align} \rm{SSTO} &= \sum_{i=1}^r \sum_{j=1}^{n_i} (Y_{ij}-\overline{Y}_{..})^2 \\ &= \sum_{i=1}^r \sum_{j=1}^{n_i} [(Y_{ij}-\overline{Y}_{i.})+(\overline{Y}_{i.}-\overline{Y}_{..})]^2 \end{align}  I'm actually reading through Casella and Berger's "Statistical Inference" (pg 536), but the same jump occurs in both.  Sorry, I was never the best at algebra... would someone please explain this.


In what order do unblocked creatures assign damage?

Scenario:  Player A has two unblocked creatures attacking player B, each with power 3 with an ability that triggers upon dealing combat damage to a player, let's say  and . Player B has a damage prevention effect preventing the next 4 damage dealt to himself. No creatures have first strike and no other replacement or prevention effects are active.  Which of the two creatures abilities triggers and why?


"A, together with B" singular or plural?

Which is the correct form of the following structure?     A, together with B, provide an efficient means of...   or     A, together with B, provides an efficient means of...   Certainly, "A provides", and "A and B provide". My intuition tells me that the second form is correct because A is the subject and is singular.


What is the value of Vout if we know the value of Vin in this case?    It is a buffer amplifier, but it has two extra resistors so I think that the gain is smaller than 1, but how small?    (Vin-V3)/R1=0 <=> Vin-V3=0 => Vin=V2=V3  (Vout-V2)/R2=0 <=> Vout-V2=0 => Vout=Vin=V2=V3


Here's what I am trying to do in (jquery,html):  The aim is to make it so that when I hit the switch (basic/advanced) a block of html is added to the existing html. Within this new block there will be another switch (less/more) which should added another block.  However I can't seem to (less/more) switch to work. In fact the function is not running at all.  The function that corresponds to the (basic/advanced) switch is:  var selectInvestment = "basic"; function expandInvestment(){     $("input[type=radio][name=expandInformation]").click(function(){         selectInvestment = $(this).val();        var huge = 'huge block of html code in here';         if(selectInvestment == "advanced"){             $('.investmentBlock').empty();             $('.investmentBlock').append(huge);             expandedExpenses();         } else if(selectInvestment == "basic"){             $('.investmentBlock').replaceWith("<...more html code...>");         }     }); }   And it's similar for the less/more switch.  Here is jsfiddle preview.


Jasperreport conditional coloured cell without value

No matter how silly this requirement is I would like to know your opinion and advices on this topic. Using jasperreport in our system we have requirement to show color instead of an actual value. Is there any chance how to set background color as a reference of value in the cell (e.g. value is #ff0000 which should be set as bg color and value should be hidden)?   Thanks


Stupidly, I upgraded my ancient laptop to 13.04 and am now in a world of slowness. I'm running in dual-boot mode alongside Win XP. I've seen other similar requests and the answer is reinstall. My question is how? I've put my 12.04 cd in and it boots ok and asks me if I want to install but then just hangs.


assigning values to global variables in python

Sorry for the beginner question. In the below code, the output I'm getting is "Original" and not "Function". Doesn't the value of name change after passing through the function? Thanks global name name = "Original"  def test():     name = "Function"  test() print(name)


Why does this commented out function not achieve the same result as the if-statements below it? How can I get it to function?

So, I'm pretty new to JavaScript and I'm trying out some beginner projects on my own. I want to make a clock and add a 0 before single digit times. I have achieved this through multiple duplicate if-statements but when I try to translate that to a function I fail. I assume it is not working because I am trying to set a value to another value or I am comparing them by accident. I am in a bit of a mental knot at the moment.  function setTime() {     var today = new Date();     let hour = today.getHours();     let minute = today.getMinutes();     let seconds = today.getSeconds();     let period = '';      if (hour <= 11) {         period = 'AM';     } else if (hour >= 12) {         period = 'PM';         hour -= 12;     }      // function twoDigit(timeValue) {     //     if (timeValue.toString().length === 1){     //         timeValue = '0' + timeValue;     //     }     // }      // twoDigit(seconds);     // twoDigit(minute);     // twoDigit(hour);      if (hour.toString().length === 1){         hour = '0' + hour;     }     if (minute.toString().length === 1){         minute = '0' + minute;     }     if (seconds.toString().length === 1){         seconds = '0' + seconds;     }       const timeDiv = document.getElementById('time-display');     timeDiv.innerHTML = hour + ':' + minute + ':' + seconds + ' ' + period;     document.body.appendChild(timeDiv); }  setInterval(setTime, 1000);


What are the differences between $...$, $$...$$, \(...\), and \[...\]?

The title says it all. I haven't been able to find the answer yet, so any help would be appreciated.


I'm not an expert in LaTeX, and just want to ask. How can we build the following table in LaTeX?    Thanks.


I have an embedded device running a linux environment built with Yocto.  I have both openssh-server and nginx running, both of which take 1 minute to start because they are waiting on enough entropy:  From dmesg: 56.338824] random: crng init done  uname: Linux beaglebone 5.0.12-jumpnow #1 Wed Sep 25 22:09:50 UTC 2019 armv7l GNU/Linux  Is there any way I can speed up this process?  Perhaps cache some entropy between reboots?  There is no mouse or keyboard, and may be very little to no network traffic for faster entropy generation.


How do I wait for console input like 2 seconds?

The whole Idea is that I give the player 2 seconds to type Dodge or Attack. If they havent typed Dodge or Attack they die. I cant figure out how to break out of the ReadLine. I someone can help me thanks. (C# Console Application)


Do portraits of wizards only have their characters or also their memories?

Do the magical portraits, like the ones of the headmasters of Hogwarts, still have all their memories?  Hypothetical example: If Harry's parents were on a portrait, would they just love Harry and be good parents for him to have a nice talk with OR would they be able to tell him it wasn't Sirius who betrayed them but Peter Pettigrew?


How to crop other layers to a selection from a different layer? Photoshop

In photoshop, let's say I have 3 layers. Layer A and B have default background images. In layer C, I make the shape of something, let's say a car. I select the outline using the Quick Selection Tool. How do I crop Layers A and B to this selection, so that I can get the portion of those images to this selection?


Sets with no asymptotical density over $\mathbb N$

Let's consider the  defined by:      Take $ A\subset \mathbb N$; define the sequence $x_n= \dfrac{|A\cap[1,n]|}{n}$, and then if $\lim\limits_{n\to\infty} x_n$ exists, call it $d(A)$, the density of $A$ over $\mathbb N$.   My teacher said that the collection of sets that have a natural density is not an algebra, but I don't know why. I can't even find a set that does not have a natural density.  Please help me )=


Let's assume that I've got two text file a, b.  $cat a a a a a a a  $cat b b b b b b b   Then, I want to merge these two file vertically by using paste. The merged file is shown bellow  a a a a a a b b b b b b   NOT  $paste a b > AB $cat AB a a b b a a b b a a b b


How would you test for both differences in mean AND differences in variance?

Suppose I wanted to test for a difference in BOTH the mean and variance, how would I go about constructing a test statistic for this purpose?  I suppose my null hypothesis would be that the mean and variance in one population are the same as the mean and variance in another, whilst the alternative hypothesis would be that they differ.


Interpretation of mean absolute scaled error (MASE)

Mean absolute scaled error (MASE) is a measure of forecast accuracy proposed by .  $$MASE=\frac{MAE}{MAE_{in-sample, \, naive}}$$  where $MAE$ is the mean absolute error produced by the actual forecast;  while $MAE_{in-sample, \, naive}$ is the mean absolute error produced by a naive forecast (e.g. no-change forecast for an integrated $I(1)$ time series), calculated on the in-sample data.  (Check out the  paper for a precise definition and formula.)  $MASE>1$ implies that the actual forecast does worse out of sample than a naive forecast did in sample, in terms of mean absolute error. Thus if mean absolute error is the relevant measure of forecast accuracy (which depends on the problem at hand), $MASE>1$ suggests that the actual forecast should be discarded in favour of a naive forecast if we expect the out-of-sample data to be quite like the in-sample data (because we only know how well a naive forecast performed in sample, not out of sample).  Question:  $MASE=1.38$ was used as a benchmark in a forecasting competition proposed in this . Shouldn't an obvious benchmark have been $MASE=1$?  Of course, this question is not specific to the particular forecasting competition. I would like some help on understanding this in a more general context.  My guess:  The only sensible explanation I see is that a naive forecast was expected to do quite worse out of sample than it did in sample, e.g. due to a structural change. Then $MASE<1$ might have been too challenging to achieve.  References:   Hyndman, Rob J., and Anne B. Koehler. "" International journal of forecasting 22.4 (2006): 679-688. .


Let $p$ be a prime number, and consider the mapping called the trace $$ Tr \quad : \quad \mathbb{F}_{p^n} \ \longrightarrow \ \mathbb{F}_{p^n} \quad : \quad x \ \longmapsto \ x + x^p + x^{p^2} + \cdots + x^{p^{n-1}}$$ My syllabus Abstract Algebra states the following:   Every element $x \in \mathbb{F}_{p^n}$, is mapped to $\mathbb{F}_p$. The restricted mapping $Tr' \ : \ \mathbb{F}_{p^n} \ \rightarrow \mathbb{F}_p $ is surjective.   I failed to prove both these statements, and I ask you for some help.    Research effort for the first statement  We can see $\mathbb{F}_{p^n}$ as a vector space with the scalar field $\mathbb{F}_p$. I showed that $Tr$ is a linear mapping in this setting. I convinced myself that the mapping is not an ismorfism in general by looking at the case where $p=n=2$ and $x\neq 0 \neq y$. Assume that $Tr$ is multiplicative. then $$Tr(xy) \ = \ Tr(x)Tr(y) \quad \iff \quad xy + x^2y^2 \ = \ (x+x^2)(y+y^2) \ = \ x^2y^2 +xy^2+x^2y +xy$$  and by substracting we see $$x^2y+x^2y=0 \quad \iff \quad xy(x+y) = 0 \quad \iff \quad x = -y$$ And this is not generally true in a field with four elements... I had no inspiration to continue some other way.  Research effort for the second statement  I knew that for all elements $x \in \mathbb{F}_p, \ Tr(x) = \sum_{j=1}^n x^{p^j}=\sum_{j=1}^n x$. If this the mapping would be injective here, we would be done since the sum $x+ \cdots +x$ is an element of $\mathbb{F}_p$. If $p$ divides $n$ though, this won't work because every element $x \in \mathbb{F}_p$ would be mapped to 0.    I hope you can provide me hints to prove the statements. Thank you for your time.


How to skip the 1st key in an array loop?

I have the following code:  if ($_POST['submit'] == "Next") {     foreach($_POST['info'] as $key => $value) {         echo $value;     } }   How do I get the foreach function to start from the 2nd key in the array?


Why does Voldemort become more snakelike?

So we know that Voldemort's appearance became more snakelike as he made more horcruxes and dove deeper into dark magic, but why did he become more like a snake and not more like any other animal or creature?    Relate:


Set standard default scaling of \includegraphics

I am using Sphinx and the plantuml package to include UML diagrams.  The plantuml package for Sphinx generates the following LaTeX code:  \includegraphics{%s}   Anyways - the diagrams are to big, so what I want is   \includegraphics[scale=0.75]{%s}   Can I - without patching the plantum package - set a default scale for \includegraphics in my LaTeX preamble?


Where are GNOME keyboard shortcuts stored?

I usually load a new version for every release to keep my OS fresh while preserving the last version on another partition as backup. I also employ a lot of custom key mappings.  I've figured out how to transfer the majority of my configuration across systems so far but I can't figure out where the custom keyboard shortcut mappings are stored.  Does anybody know where gnome puts these? Are there separate user config (i.e., ~/) and system config (i.e. /etc) files?


Let $\mathbb{M_n(\mathbb{R})}$ denote the set of all $n\times n$ matrices with real entries (identified with $\mathbb{R}^{n^2}$ and endowed with its usual topology) and let $GL(n;\mathbb{R})$ denote the group of invertible matrices. Let $G$ be a subgroup of $GL(n;\mathbb{R})$. Denote $$H=\left\{A\in G~~\bigg|~~\begin{array}{}\exists~\varphi:[0,1]\rightarrow G~\text{continuous}\\ \text{such that}~\varphi(0)=A,\varphi(1)=I\end{array}\right\}$$ How can I show that $H$ is a normal subgroup of $G$?


Is it possible to use Boot Camp with Windows 10 from an external HDD?

I need to run Visual Studio on my MacBook Pro and I need Windows to do that. The easiest and well known way to install Windows on a Mac is by running the Boot Camp app on the Mac and let it do what's necessary. The problem is that I don't want to partition the Internal SSD so the remaining option is to install Boot Camp Windows 10 on an External Drive and boot it every time I need it by plugging in my external USB 3.0 HDD. Is this achievable?


How can this "illegal geometry" problem be possible?

Using 2 triangles each with base of 8 and height of 3, and 2 trapezoids with heights of 3 on top, 5 on bottom and height of 5, these four figures can create an area with 64 units squared. However, when rearranged as a rectangle with 13 x 5=65, one additional unit squared seemed to have been created. How is this possible?


Why isn't it allowed to use a flash when taking pictures in a certain place?

When I go to, for example, a museum I try to take some pictures.  Sometimes the museum staffs forbid me to use a flash. Do you know the reason? I don't think it is related to photo-electric effect, right?


Can you use external money to pay trading commissions in tax-free and tax-deferred accounts?

I contribute the max to my Roth IRA every year ($5500 in 2013, for example). However, let's say I use that money to buy two stocks, with a commission $10 each, so I am effectively only contributing $5480. Admittedly this is pretty small but that extra $20 would have compounded, and if I follow this pattern every year it is like a 0.36% expense ratio. The same would apply to tax-deferred accounts like a traditional IRA. So I am wondering, is it possible to use external money (aside from the $5500 Roth contribution) to pay trading commissions? First of all, is this legal? I hypothesize perhaps not if the government wants to discourage lots of trading in tax-advantaged accounts. If it's legal, do any brokerages support this?


How to specify installation directory when installing packages

I'm somewhat new to linux, in college its the preferred by my computer science professors so I decided to install Ubuntu and Kubuntu alongside my windows 8 installation. Now, here's my problem. I read somewhere that its best to keep files in a separate partition than your linux installation, so if you ever upgrade, you don't lose all your stuff. So I created a large partition (800 gigs) where I store all my photos, music, etc. for all my Operating Systems. Here's a couple of my questions.   I'm at Ubuntu 14.04, if I update to 14.10, will my currently installed programs like unrar, chromium, be compatible with 14.10?  If so, then would updating remove them since they are on the same partition as the linux installation?  If this is true, then for future reference, can or how do I specify an installation directory when installing packages using aptitude/apt-get, compiling myself, or from the software center?    I would like to have my installed packages on a separate partition if its possible. Thanks in advance :)


As "lousy" is a pejorative for someone or something being infested with lice, why is it pronounced with a "z" instead of an "s" sound?  OTOH, when a person is called a "louse," the "s" sound is used.  Doubtless most people who use the word (lousy) don't really know what they're saying, thus the mispronunciation, but how did it get started in the first place?


question on probability of roll of one dice

this is the scenario.  roll one dice 6 times and note the result of each roll.  lets say the results are the following. 3, 3, 6, 2, 1, 4.   this will become the standard sequence.  begin to roll the dice again.  As soon as the next 3 is rolled, then what is the probability that the next 5 rolls will be exactly has follows.  3, 6, 2,  1, 4 ? The remainder of the standard sequence.


I have an mp3 audiobook and each track has exactly 1 second of static at the end. Is there a way to bulk cut out last second from each track?


NULL to 0 values in vactor attribute table in QGIS

I need to converte NULL values to 0 values with the overall goal of sum up two columns in attribute table in QGIS. Since one of these colums has NULL values, the new column with the sum also appears with NULL value (instead of preserving numeric value of other column).  I have tried Selecting column by all NULL value and putting 0 in Expression Field but that does not work.   Any ideas on how to do it?


Efficiently selecting a set of random elements from a linked list

Say I have a linked list of numbers of length N. N is very large and I don’t know in advance the exact value of N.   How can I most efficiently write a function that will return k completely random numbers from the list?


Which is better: side quests after killing the warrior or Playthrough 2?

My question is, once I beat the warrior should I do all the sidequests in Normal before starting TVHM or should I go right to TVHM once it becomes available?    I just bought the game and have been playing with some friends who are higher level than me so that we could enjoy the Tiny Tina DLC together.  As a result, I leveled up pretty fast without doing much of the main story quest or side quests.  Now I'm a level 32 commando and haven't finished the main storyline in normal (Just finished "Where angels fear to treat Pt 2").  I get almost no XP from kills on missions.  I still have tons of sidequests.  I imagine some of them might give good loot, or be fun to play.  It it better to go to Playthrough 2 or should i do the sidequests in Normal first?  EDIT: changed question title and some wording for clarity


Olympiad inequality $\frac{a}{2a + b} + \frac{b}{2b + c} + \frac{c}{2c + a} \leq 1$.

I want to prove that for $a, b, c > 0$ we have $\frac{a}{2a + b} + \frac{b}{2b + c} + \frac{c}{2c + a} \leq 1$.  My approach:  I know that each of the individual terms is lesser than $\frac{1}{2}$ because of it's form. I am familiar with the Cauchy-schwarz inequality and the AM-GM-HM inequality. I tried using AM-GM but could not get anywhere because of the way the inequality is structured. Similarly I tried using Cauchy-schwarz as well.  I just need some intuition/hints on how to actually reduce this to a feasible form to solve and not the actual answer because it does not provide me with the necessary intuition which I need as I am a beginner when it comes inequalities. If I can't use these 2 inequalities, is this problem best tackled with some other inequality?


What lenses are considered wide-angle zoom/prime for Nikon D5300

I'm planing to go on a trip where I plan to do some landscape photography. While I started out with 18-105mm lens, I noticed the quality can be poor around the edges in some cases and I know it's really not the best lens to do landscapes.  While I read  and , I'm still not sure which lenses to use as wide-angle.  So I'm looking for sharper quality as my current lens and wide. I've seen  review of 18-55mm VR which says the quality is good, but I'm not sure is this wide or isn't.  So which lenses should I be looking at for a beginner to mid range for my Nikon D5300 camera?


Detecting if an IDataReader contains a certain field before iteration

So I'm using an IDataReader to hydrate some business objects, but I don't know at runtime exactly what fields will be in the reader.  Any fields that aren't in the reader would be left null on the resulting object.  How do you test if a reader contains a specific field without just wrapping it in a try/catch?


My Canon camera realize videos with the characteristics described in the picture.    The problem is that those files are huge (1Gb for 2 minutes). Is there any application which allow me to compress or resize the films already made?


How do you find the intersection(s) of two circles with equal radii?

I have two circles with the following equations: \begin{equation*} (x-a_1)^2+(y-b_1)^2=r^2 \\ (x-a_2)^2+(y-b_2)^2=r^2 \end{equation*} The two radii are equal. How do you find the intersections of any two circles with equal radii?


SOQL to find all the recordTypes assigned to a profile or a user

Need to show all the record types created on Task object assigned to the logged-in user. I did not find any relation between the RecordType object and profile which can give me the details. Tried querying record type object with different users of different profile but always getting all the available records types irrespective of record types assigned to the logged-in user. How do get the assigned record types?


How to install Ubuntu 32-bit on Asus C300 chromebook

I have just purchased a chromebook, Asus C300, in hopes that I would be able to install ubuntu on it instead of chrome os. The other options I see are chrubuntu and crouton but neither really give me what I want as I don't have any need for chrome os and would rather free up the disk space.   So right now I have a 32bit copy of 14.04 on a flashdrive (I did it correctly via a windows machine). I turned OS verification off on my chromebook and entered it into developer mode which took a few minutes. But when I do recovery mode (escape + f3 + power) it says that the usb device does not contain chrome os. SO I'm doing something wrong but I don't know what. Any advice on how to proceed further would be greatly appreciated


How to run a program from the command line and still be able to work on the command line while it runs?

Suppose that I want to run a Java program so I would type   java myProgram   and then suppose that it prints some output to the screen but takes a few hours to finish running. If I want to keep working on the same terminal while it runs, what is the command that I should use? I tried & at the end and it did not seem to work.


Remove autocomplete from a SELECT with HTML

I have a problem with the autocomplete in HTML, I'd like to remove it from a SELECT in a web page, so it doesn't appear over the page:      This is  what I want because I'm printing the result in the bottom.     <form>     <input type="text" id="nameSearch" name="nameSearch" onkeyup="searchInput(this.value)">

 </form>    I tried to add the autocomplete tag, but it works only with the INPUT tag.  <input autocomplete="off">


Suppose there are $2$ permutations given by $p$ and $q$. I need to check whether $p$ belongs to the group generated by $q$, and if so, it's representation in a power of $q$. In other words, I've been given $p$ and $q$, I need to check whether $\exists i \in \{ 0,...,|q|-1 \} \text{ such that } p = q^i$ I know that if $m = \gcd(i, |q|)$, then $|q^i| = \frac{|q|}{m}$. Now, say that such an $i$ exists. Then, $$ |p| = \frac{|q|}{\gcd(i, |q|)} \Rightarrow \gcd(i, |q|) = \frac{|q|}{|p|} $$ Thus, a necessary condition for such an $i$ to exist is: $|p|$ divides $|q|$ Say that this holds, and $\frac{|q|}{|p|} = r$, where r is an integer. Then we just have to solve $\gcd(i, |q|) = r$ for $ i \in \{ 0,...,|q|-1 \}$. Can this be done? If not manually, then by some efficient algorithm? (Note: Just looping over all values of $i$ is not efficient as $i$ may be very large) Edit: Another way I can think of solving this is by writing both $p$ and $q$ as product of disjoint cycles: $$ p = c_1c_2\ldots c_k \text{ and } q = d_1d_2\ldots d_l $$ And thus, as disjoint cycles commute: $$ p^i = c_1^ic_2^i\ldots c_k^i $$ How to proceed after this?


Automatically Mount Encrypted Core Storage Volume (10.14.4+)

Prior to Mojave 10.14.4, macOS would automatically attempt to mount locked Core Storage volumes, and if the necessary password was found in the current user's keychain this would occur automatically.  I've taken advantage of this behaviour until now to allow me to have multiple encrypted volumes that are all mounted automatically by successfully logging in to a user account on my encrypted startup volume.  However, macOS no longer appears to be attempting to mount Core Storage volumes automatically, despite the necessary passwords being in either my user keychain, or the system keychain, forcing me to mount them manually with Disk Utility. This isn't ideal as it ties the volumes to the user account, meaning if I log out the volumes are locked again.  This behaviour differs from encrypted APFS volumes, which mount automatically exactly as before. I know Apple is pushing us to move to APFS, but with still no conversion for AppleRAID (I'm not keen to erase and restore a multiple terabyte volume just to switch), and no use for Time Machine which still doesn't support an APFS backup volume.  Is there a way to restore or securely emulate the previous behaviour such that the volumes are unlocked automatically for all users?  In case the specifics of my setup are useful; my startup volume is an APFS encrypted volume that only my admin account is authorised to unlock, but I use other, standard, user accounts (one for work, one for general use etc.) when actually using my system. I then have an AppleRAID volume of several disks using Core Storage encryption, and a CS encrypted Time Machine disk.


How to find the greatest prime number that is smaller than $x$?

I want to find the greatest prime number that is smaller than $x$, where $ x \in N$. I wonder that is there any formula or algorithm to find a prime ?


I am trying to replace some HTML Tag with another HTML Tag with php or jquery .   My Current Tag (Default) :
  Home
   I want to replace above HTML tag with
  Home
     Example :   Default tag :
 tag
  Replaced tag :
 tag
  I already search many articles on stackoverflow but didnt founded solution for it.   Thank in advance


Large update taking too long; looks like it is updating more records than I have

I am trying to do an update on a table that has 4 million records. The main table is indexed on SerNum a unique field. I use a temp table to update from that also has a unique index on SerNum. I am told this should happen fast but it's taking hours. It's been running for 2 hours and if I add up the rows affected I get 5,260,000 which is weird because I only have 3,869,000 records in the table. The select into the temp table shows it has 3,390,954. Here is what I have so far can this be more efficient?   USE IMB_TraceData GO  IF OBJECT_ID('tempdb.dbo.PRIMARY KEY (lname,') IS NOT NULL     DROP TABLE #MaxDate; GO  -- ****************************************** -- Create Work Table -- ****************************************** SELECT * INTO #MaxDate FROM     (     SELECT  *     FROM    (             SELECT  *,              ROW_NUMBER() OVER (PARTITION BY TR_SerNum              ORDER BY TR_Scan_Date DESC) AS rn             FROM  Trace_Return_Table             ) a     WHERE   a.rn = 1     ) AS n GO CREATE INDEX IDX_SerNum ON #MaxDate(TR_SerNum) GO  DECLARE  @UPDATES TABLE (PK_ID int NOT NULL Primary KEY) DECLARE @x INT  SET @x = 1 SET ROWCOUNT 10000  WHILE @x > 0     BEGIN         BEGIN TRANSACTION         UPDATE TOP (10000) IMB_TBO_Data.dbo.The_Big_One          SET TR_Scan_Date = n.TR_Scan_Date,             TR_Facility_Id = n.TR_Facility_Id,             TR_Operation_Code = n.TR_Operation_Code         OUTPUT inserted.HT_SerNum INTO @Updates         FROM IMB_TBO_Data.dbo.The_Big_One t         INNER JOIN #MaxDate n             ON t.HT_SerNum = n.TR_SerNum         WHERE NOT EXISTS          (SELECT * FROM @UPDATES AS Updates         WHERE UPDates.PK_ID = t.HT_SerNum)         SET @x = @@ROWCOUNT         COMMIT TRANSACTION     END  SET ROWCOUNT 0


How to create an alias for a sequence of commands?

I know it for one command but how to work with a sequence?


What would be a suitable textbook of first semester physical chemistry?

I am going to take PChem I in my biochem dept next sem, which is a watered down version of the PChem course in Chem dept. It basically covers thermodynamics and a little bit of quantum stuff. The syllabus says there is no required text, since course notes will be available once we register for class. But I do want to get ahead of class by reading books. I have several books at hand, please give me suggestions on which one should I use and if you have any good free lectures, feel free to post links as well  Intro to Molecular thermodynamics by Hanson&Green, PChem for Chem and BioSci by Chang,Molecular Driving Forces by Dill&Bromberg, PChem: A molecular approach by McQuarrie, An introduction to thermal physics by Schroeder,Pchem by castellan, Callen's thermodynamics text and also Fermi's  Personally, I found Hanson, Castellan, Dill, and Chang are pretty good, haven't read any other


why code printing garbage value on screen with input string?

I was trying to make string type datatype in c with dynamic memory allocation.  my code is printing the characters which are inputted by the user but it is also printing some garbage value in next line. Why is this happening?  #include <stdio.h> #include <stdlib.h>  void main(void) {     int n = 1, i = 0;     char a = 0;     char *str = NULL;     str = malloc(sizeof(char) * (n));     printf("Enter string : ");     while (a != '\n')     {         a = getchar();         str = realloc(str, sizeof(char) * (n));         str[i++] = a;         n++;     }     printf(str);     free(str); }   input:   "q"   output:   q  "garbage value"


ArrayList time taken by first element retrieval

I know time taken by get() operation in ArrayList is O(1), however I have noticed that first element always taking either more or equal time compare to others. I tried 100's of time. I know it does not matter much as the difference is in nano seconds, but would like to know if there is any logical explanation or it's just Random.  Here' is my program:  import java.io.IOException; import java.util.ArrayList; import java.util.List;  public class ListTest {     public static void main(String[] args) throws IOException {          for (int i = 1; i <= 20; i++) {             System.out.println("============== Iteration ======= "+i);             List<String> list = new ArrayList<String>();              for (int j = 0; j < 50000; j++) {                 list.add(j + "");             }              long t1 = System.nanoTime();             list.get(0);             long t2 = System.nanoTime();             System.out.println("time (0) :: " + (t2 - t1));              t1 = System.nanoTime();             list.get(20000);             t2 = System.nanoTime();             System.out.println("time (20000) :: " + (t2 - t1));              t1 = System.nanoTime();             list.get(49000);             t2 = System.nanoTime();             System.out.println("time (49000) :: " + (t2 - t1));         }      } }   Output:  ============== Iteration ======= 1 time (0) :: 12000 time (20000) :: 1000 time (49000) :: 0 ============== Iteration ======= 2 time (0) :: 17000 time (20000) :: 14000 time (49000) :: 16000 ============== Iteration ======= 3 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 4 time (0) :: 3000 time (20000) :: 1000 time (49000) :: 0 ============== Iteration ======= 5 time (0) :: 16000 time (20000) :: 8000 time (49000) :: 8000 ============== Iteration ======= 6 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 7 time (0) :: 1000 time (20000) :: 1000 time (49000) :: 0 ============== Iteration ======= 8 time (0) :: 4000 time (20000) :: 0 time (49000) :: 1000 ============== Iteration ======= 9 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 10 time (0) :: 1000 time (20000) :: 1000 time (49000) :: 1000 ============== Iteration ======= 11 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 12 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 13 time (0) :: 2000 time (20000) :: 1000 time (49000) :: 1000 ============== Iteration ======= 14 time (0) :: 1000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 15 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 16 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 17 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0 ============== Iteration ======= 18 time (0) :: 1000 time (20000) :: 1000 time (49000) :: 1000 ============== Iteration ======= 19 time (0) :: 1000 time (20000) :: 1000 time (49000) :: 0 ============== Iteration ======= 20 time (0) :: 2000 time (20000) :: 0 time (49000) :: 0


How can I calculate the following sum involving binomial terms:  $$\sum_{k=0}^{n} \binom{n}{k}\frac{(-1)^k}{(k+1)^2}$$  Where the value of n can get very big (thus calculating the binomial coefficients is not feasible).  Is there a closed form for this summation?


Definition of holomorphic vector bundle using sheafs

Can somebody give me a general idea how to define a vector bundle of rank $N$ if we have a sheaf, which is locally given by $N$ holomorphic functions?


How should I address someone with a known name and unknown gender?

When communicating with foreign cultures, the gender of the addressed person is  not always clear from the name. What would be a professional way to address someone in this situation. (Dear Mr or Ms SomeForeignName looks awkward).  A hack I generally use is to do a google image search for the name, but this isn't always accurate in all cultures. What's the solution here?


I'm new to Blender I've been trying to make this form but some things keep getting in the way. Some weird faces keep creating themselves when I try to fill some parts of the mesh (the "white grey" parts ) So why do those are created ? How can I erase them while keeping the main face I wanna have?


My play store is not working it just say's error while retrieving information [RH-01]


dynamically added hyperlink in table click

I am adding dynamically hyperlink and want to execute click event as below when ever user clicked on it but it is not firing up.

   When user selected some option  in DropDown then it goes and get areas from server then ajax get calls this function by passing data to this function   function updateAssignedAreas(data) {              debugger;             var areas = data.split(',');             $.each(areas, function (i, item) {                 $('#assinged_areas > tbody:last').append('
' + item + '	' + ''                     + '
');             });         }   This is the function when user click on unassign must call but not firing at all    $('.btn-danger').click(function (parameters) {             debugger;         });


It is 10 cm on the map. That is 100 km in real terms.   I am proofreading and it seems odd that the writer always uses that in these cases. I would have said this.     Who is right and who is wrong?


Bound on difference between irrational square root and rational number

I'm trying to show that if $\alpha$ is the square root of a non-perfect square $d$, then for any rational $p/q$ there's a positive real $x$ such that $|\alpha - p/q| > x/q^2$. I'm having trouble starting on the problem, could someone give a hint? Thanks


Is a goal scored if the goalkeeper, but not the ball, enters the goal?

Is a goal scored if a goalkeeper holding the ball enters the goal, but keeps the ball out of the goal?


Generalized Chi-Squared Distribution PDF

Let $\mathbf{X} \sim \mathcal{N}_n( \mathbf{m}, \mathbf{C})$ be an $n$-dimensional gaussian vector, where $\mathbf{C} \in \mathbb{R}^{n \times n}$ is not diagonal, but it is positive-definitive, $\mathbf{C} \succ 0$, and $\mathbf{m} \neq \mathbf{0}$. Let $$ Y = \| \mathbf{X} \|^2 $$ where $\| \cdot \|$ denotes the $L_2$-norm (Euclidean norm), should follow a . Unfortunately, the Wikipedia page contains little information.  My question is: What is the PDF (probability density function) of $Y$ ?


To prove that for any element a of a group G the center Z(G) is properly contain in the centraliser of a in the group G CG(a)

I has idea on abstract algebra, group theory ect. Ihave also check in the test block i have but could not get the solution. And also check the net but also no solution.


Why elements in a vector need to be copy constructable?

I have this question because I am reading the section for auto_ptr. It says auto_ptr cannot be saved in a vector because of its destructive copy and assignment. I can understand it somehow and one example I can think of is something like auto_ptr ap = vec[0] will surprise me. But what if I use it cautiously and do not do this, can I store auto_ptr in a vector? Is there any deeper reason why I cannot store? Maybe the implementation of vector internally needs this assumption that elements need to be copy constructable?  Thanks.


Why, when subtract a decimal number in system out the output not correct

why when i print this code in print statement the output will be not correct.  System.out.println(3.15 - 3);   the output is:  0.1499999999999999   i think the output must be.  0.15


Why did Owen Chase not fire his harpoon at Moby Dick?

In movie In the Heart of the Sea, when Owen Chase finally faces the big white whale (later named Moby Dick) with his harpoon, why does he not do it?


Is saving MySQL username/password in the php.ini file secure?

I would like to know if it is secure to save the username, password, server etc. in the php.ini file so when I connect to the MySQL server I don't have to always put the parameters? Also, can this information (saved in the php.ini) be viewed or retrieve by any kind of methods (like phpinfo() or something like that)?


If I want to fly from departure location and return to departure location on specified date but no specific destination.   Is there a flight booking site that allows no specific destination?


I have windows 7 ultimate in my laptop. C:, D:, E:, F:, G:,. Now C: have Windows 7 Os, D: is empty, E:, F:, G: have some important files. Now how do i install ubuntu in D:. I already tried but d: is permanently disabled in windows 7 os. NOw i ask step by step installation in my laptop installation path is D: is empty  with out deleted in my other drive files (E:, F:, G: - have some important files). I confused swap space when partition please help me installation ubuntu in my laptop.


Programming pattern to generate VGA signal with micro-controller?

I want to generate VGA signal with micro-controller (like TI Tiva ARM which runs at 90/120Mhz speed).  I'm not sure how to make accurate timings with micro-controller. Which programming pattern I need to use?  Do I need any inline assembler code? How to wisely use interrupts?  Would be great if anybody show some pseudo code how to generate VGA signal.  I successfully generated VGA signal with FPGA. But I just can't figure out how to do it with MCU.


TAR 6 GB worth of files into separate 1.9 GB TAR files

I have 28,000 files of size 6.7 GB in the directory aaa/input. I need create TAR files in the directory aaa/output, such that each TAR file cannot exceed 1.9 GB, so I have to tar the 28,000 files into 4 TAR files (6.7/1.9) as Log_(current date)_01.tar Log_(current date)_02.tar ... etc.  such that each tarball is less than 1.9 GB. Is there a way to do this using a Unix script?


How to Re-Add Windows XP to grub menu after Ubuntu 11.10 Re-install

Basically, I messed up my partitions and decided to do a full re-install of both Windows XP and Ubuntu 11.10 (I know that 11.10 is outdated, but I was planning to do an update to 12.04 as soon as I got everything happened). Here is a sequence of what I did:   Installed Windows XP onto 20gb of hard-drive space Installed Ubuntu 11.10 onto the remaining 10 gb of space using the advance setup option where I partitioned: (1gb swap, 200mb /boot, and 8.8gb / , (see screenshot)) Trouble struck, when I rebooted, grub2 didn't show Windows XP under my boot options. I ran sudo update-grub but it still didn't find windows I opened gparted and added the 'boot' flag to my windows xp partition (I was getting desperate and didn't know what to do)   And now, I'm stuck with only Ubuntu, and I don't want to have to re-install both Ubuntu and Windows to get grub working again.   Please note, I have seen  and  but I couldn't find anything useful.   Thanks a lot,  DevNewb


How to calculate private key from given public key RSA pair?

A public key for RSA encryption given by the pair (143,11). I am confused to solve it because if I select p =11, q = 13 so, n=143  then e should be 7?


Triangle Inequality for a type of Sobolev space norm

I am attempting to show the triangle inequality holds for the following norm, which is defined as: $||f|| = \bigg( \int_0^1 (|f|^2 + |f'|^2) \ dx  \bigg)^{1/2} \\$.  My attempt thus far; I am confused on where to go next? Any help would be great.  $\begin{align*}     ||f+g||^2 &= \int_0^1 |f+g|^2+ |f'+g'|^2 \ dx \\     &= \int_0^1 |f|^2 + 2|fg| +|g|^2 |f'|^2 + 2|f'g'| + |g'|^2 \ dx \\     &= \int_0^1 |f|^2 + |f'|^2 \ dx + \int_0^1 |g|^2 + |g'|^2 \ dx + 2 \int_0^1 |fg|+|f'g'| \ dx \\     \end{align*}$


I have two dictionaries as follows:  D1={'a':1,'b':2,'c':3}  and   D2={'b':2,'c':3,'d':1}  I want to merge these two dictionaries and the result should be as follows:  D3={'a':1,'b':2,'c':3,'b':2,'c':3,'d':1}  how can I achieve this in python?


Starting to learn Nodejs in Ubuntu (New to ubuntu as well). when I use apt install nodejs , v8.x.x is getting installe instead of current v12.x.x. I tried to use nvm using from   but it is only installing node and not nodejs.  I tried to install from nodejs.org but it's just installing a tar package and I'm not sure how to install it or even if I'm able to install, do not find any easy way to update the node version.  Can someone provide me right way to install latest nodejs.  Thanks


How to print "Hello" in C without using a semicolon?

I know there are several ways to do this. Such as:  #include <stdio.h>  int main()  {        if (printf("Hello"))         return 0; }   But, how do I do this by removing the semicolon after return 0; as well?  Considering the fact that I can't use void as the return type of main()  Even this article below ignores this fact and skips return 0; statement though the return type of main() is int:


I am trying to make an if-statement that says:  If a file in this directory has .PDF extension do this, otherwise do this...  And I'm having a hard time figuring out how to do this in bash. I checked here :  first but the solutions listed either don't work or give errors I don't know how to fix. Attached below is  my script. I slightly modified the script I was working on in my previous question here:  The script is below: #!/bin/bash #shebang for bourne shell execution echo "Hello this is task 1 of the homework"  #Initial prompt used for testing to see if script ran   #shopt allows configuration of the shell -s dotglob allows the script to run on dot-files shopt -s dotglob  #loop to iterate through each file in Task1 directory and rename them #loop runs if there is a file type of ".PDF" in the folder Task1, if there isn't displays that there i sn't a file of that type and terminates  if [ [ -n $(echo *.PDF) ] ] # what should I put here???   then         for file in Task1/*.PDF;         do                  mv "$file" "${file%.PDF}.pdf"                 echo "$file has been updated"         done else                 echo "No files of that type..." fi ~             **Edit 1: ** As per Ipor Sircer's answer below I changed my script to the following: #!/bin/bash #shebang for bourne shell execution echo "Hello this is task 1 of the homework"  #Initial prompt used for testing to see if script ran   #shopt allows configuration of the shell -s dotglob allows the script to run on dot-files shopt -s dotglob  #loop to iterate through each file in Task1 directory and rename them #loop runs if there is a file type of ".PDF" in the folder Task1, if there isn't displays that there isn't a file of that type and terminates  if [ ls -1 *.PDF|xargs -l1 bash -c 'mv $0 ${0%.PDF}.pdf' ] then         for file in Task1/*.PDF;         do                  mv "$file" "${file%.PDF}.pdf"                 echo "$file has been updated"         done else                 echo "No files of that type..." fi  I get the following errors:  Hello this is task 1 of the homework ./Shell1.sh: line 12: [: missing `]' mv: cannot stat ']': No such file or directory No files of that type...  Edit 2 As per  Eric Renouf's comment fixing the spacing gives me the following script: #!/bin/bash #shebang for bourne shell execution echo "Hello this is task 1 of the homework"  #Initial prompt used for testing to see if script ran   #shopt allows configuration of the shell -s dotglob allows the script to run on dot-files shopt -s dotglob  #loop to iterate through each file in Task1 directory and rename them #loop runs if there is a file type of ".PDF" in the folder Task1, if there isn't displays that there isn't a file of that type and terminates  if [[ -n $(echo *.PDF) ]] then         for file in Task1/*.PDF;         do                  mv "$file" "${file%.PDF}.pdf"                 echo "$file has been updated"         done else                 echo "No files of that type..." fi  However if I run it twice I see the following:  Hello this is task 1 of the homework mv: cannot stat 'Task1/*.PDF': No such file or directory Task1/*.PDF has been updated  Why don't I just see the else echo since there are no files of type .PDF in the folder anymore?


I have created a function in which I am sending data through array along its index so that particular value should convert into binary, but I don't know whether I am correctly sending and returning array.  my code:   package GA;  public class test {      public void chr_intval(){          double [] array = new double[100] ;             int i=1;             array[i] = 4;             System.out.println(Genes(array,i)); // print the value contain array[1] in binary          }         @SuppressWarnings("null")     public double[] Genes(double[] j,int i){ // get the value from 1st index that is 4 hardcoded         double [] a1=null;         int k=9;         //a1[k]=0;         double d=j[i];         while(d>1)         {             a1[k--]=d%2;             d=d/2;          }            return a1;// return the value in binary that is 100      }     public static void main(String[] args) {         test a = new test();         a.chr_intval();     }  }   at console:  Exception in thread "main" java.lang.NullPointerException     at java.io.Writer.write(Unknown Source)     at java.io.PrintStream.write(Unknown Source)     at java.io.PrintStream.print(Unknown Source)     at java.io.PrintStream.println(Unknown Source)     at GA.test.chr_intval(test.java:10)     at GA.test.main(test.java:41)


Copying steam game data from one computer to another

My friend just bought payday 2 yesterday, and he doesn't want to download it because it will take a long time.   Let's pretend that there are two subject here, A and B. Both have payday, but only B has downloaded it.  A takes the game data from Steam/SteamApps/common on B's computer and copies it to the same location on his own. He doesn't know about the appmanifest so he doesn't copy it.  I asked him "Did you copy the appmanifest too?". He said no, so I uploaded my appmanifest (for Payday 2) so he can download it. I told him to place it in the steamapps file and he did.   When he restarted steam, the game was still not installed. How can he install it?


Is there a built-in command for downloading a file using the command line on Windows? I know I can get cygwin and install wget, but I would like a solution that works on any windows PC.


How can I prevent listings from replacing space characters by a weird bracket symbol?

I'm using the listings package and I'm not happy about the output I'm getting. More specifically, listings seems to replace some space characters by a weird bracket symbol. See the screenshot below. Is there a way to make this symbol disappear?    \documentclass{article} \usepackage{listings,xcolor} \usepackage{inconsolata}  \definecolor{dkgreen}{rgb}{0,.6,0} \definecolor{dkblue}{rgb}{0,0,.6} \definecolor{dkyellow}{cmyk}{0,0,.8,.3}  \lstset{   language        = php,   basicstyle      = \small\ttfamily,   keywordstyle    = \color{dkblue},   stringstyle     = \color{red},   identifierstyle = \color{dkgreen},   commentstyle    = \color{gray},   emph            =[1]{php},   emphstyle       =[1]\color{black},   emph            =[2]{if,and,or,else},   emphstyle       =[2]\color{dkyellow}}  \begin{document}  \begin{lstlisting} <?php //PFBC 3.x PHP 5 >= 5.3 session_start(); include($_SERVER["DOCUMENT_ROOT"] . "/PFBC/Form.php"); $form = new PFBC\Form("GettingStarted"); $form->addElement(new PFBC\Element\Textbox("My Textbox:", "MyTextbox")); $form->addElement(new PFBC\Element\Select("My Select:", "MySelect", array(    "Option #1", //<--- here for example    "Option #2",    "Option #3" ))); $form->addElement(new PFBC\Element\Button); $form->render();  //PFBC 3.x PHP 5 session_start(); include($_SERVER["DOCUMENT_ROOT"] . "/PFBC/Form.php"); $form = new Form("GettingStarted"); $form->addElement(new Element_Textbox("My Textbox:",  "MyTextbox"));  (My Textbox $form->addElement(new Element_Select("My Select:", "MySelect", array(    "Option #1",    "Option #2",    "Option #3" ))); $form->addElement(new Element_Button); $form->render(); ?> \end{lstlisting}  \end{document}


Understanding the basic idea of Infinity

I'm a 10th grader looking for a way to understand infinity, I watched a bunch of videos on the topic but I just couldn't get an idea. Can someone explain the idea of infinity or rather how Cantor came up with the idea and his proof for it?


Why do characteristic impedances matter only when traces are longer than half a wavelength?

Why are characteristic impedances of traces not considered when the traces are shorter than half a wavelength? I've had the same issue with light diffraction, which happens when pinholes are smaller than half a wavelength - it sort of makes sense somehow, but I can't "see" it, I don't understand how wavelengths are related to reflections (which I assume are the only reasons why we care about impedance matching). I'm trying to make the ocean wave analogy work but... Well, the fact that I'm asking this says it all.


How to work out covariance using the expected value of x,y and xy

Cov(x,y) if e(x) = 2.60 and e(y) = 2.35 and e(xy) = 7.06   i'm confused because all i know is $$cov(x,y) = \text{correlation of xy}*sqrt(x)*sqrt(y) $$


Is there a term for polishing something too early?

I imagine there must be a term/idiom/phrase for polishing something too early...  For example:   Painting the walls of a room before completing other work which may accidentally damage them. Adding detail to a section of a drawing that you may likely need to radically change later (and lose the detail work) Optimizing a software function which might be deemed unnecessary before it's even used   Though I can't seem to think of what this is called (no luck with searching either).  Originally I posted this in the 'workplace' stack exchange but was recommended to try here.


“no public key available” on apt-get update

When I do a sudo apt-get update, I encounter the following:  Fetched 189 B in 10s (18 B/s)                                                   W: There is no public key available for the following key IDs: 1397BC53640DB551 W: GPG error: http://download.opensuse.org ./ Release: The following signatures were invalid: KEYEXPIRED 1436387333 W: Failed to fetch http://dl.google.com/linux/chrome/deb/dists/stable/Release  Unable to find expected entry 'main/binary-i386/Packages' in Release file (Wrong sources.list entry or malformed file)  E: Some index files failed to download. They have been ignored, or old ones used instead.   What would be a good/recommended way to fix this?


Prove that $\mathbb{R^*}$, the set of all real numbers except $0$, is not a cyclic group

Prove that $\mathbb{R^*}$ is not a cyclic group. (Here $\mathbb{R^*}$ means all the elements of $\mathbb{R}$ except $0$.)    I know from the definition of a cyclic group that a group is cyclic if it is generated by a single element. I was thinking of doing a proof by contradiction but then that ended up nowhere.


why is the placement of the table wrong?

I'm new Latex, I want to use make a table, and it works fine. the problem that I have is the position  of table in the document :   \chapter{chapter description } \section{section name } \subsetion{subsection} here should the text be displayed  \begin{table} \begin{tabularx}{\textwidth}{p{0.3\textwidth}|c|c|c} \end{tabularx} \caption{Table Name   \label{tab:table_label}} \end{table}   the pdf result hasn't the right order,  I get  first  the table  and that the \chapter and section , subsection  I don't what I'm doing wrong   any idea ?  thanks in advance


DDoS - How to detect an attacker IP address

Someone keep attacking my server, but unfortunately I've switched my OS to the FreeBSD, as I've earlier used Debian 5.0 Lenny, and none of netstat or tcpdump commands I used on Debian, works on FreeBSD.  So how can I detect attacker IP address so I could block this guy in the firewall?


Why is it a good idea to invest only in a Roth IRA or a no-load mutual fund invested in an indexed fund of the Dow or S&P 500?

Basing this question on :     This is just a matter of simple math.      Saving accounts earn less than 1% per year.      CDs usually pay less than 2.75% per year.      Inflation is 1.9%-2.9% so deduct that.      401ks well invested can yield 4%-7%      The only thing worth investing in is a ROTH IRA or a no-load mutual   fund invested in an indexed fund of the DOW or S&P 500.   The Roth IRA account is good, I suppose, because of the tax free / deductible nature of withdrawing and contributing to the account.  However, why a no-load mutual find invested in an indexed fund of the S&P? Is it because you don't have to worry about figuring out how to diversify your portfolio because the index fund already takes care of that?  I'm skeptical of this answer. If you disagree, what do you think is a better strategy?


Status of "Reviews Completed" in a springer journal

We had submitted to a springer journal (field: Bioinformatics). Two reviewers reviewed the paper and both strongly and unequivocally recommended publication after a few minor changes, e.g., grammatical, a few small clarifications and change of background colors (from black to white for printing purposes). The editor seemed to be very happy about the reviews as well. However, in the tracking site it displayed 'Major Revision' probably as a norm - though frankly there was nothing major in the suggested revisions and both reviewers actually used the term 'minor' in their reports ! It took us no more than two days to do all suggested changes and resubmit. The second round of review has now taken little more than a month, out of which the status was 'under review' for last two weeks and 'Reviews Completed' from last two days. I have never encountered this status before elsewhere so wonder what it means ! Is it similar to 'Pending decision' or indicative of something more than that ? This is my first communication as a corresponding author, so, not to mention, am a bit tensed.


Would days be longer as the polar ice caps melt?

I got question in my mind striking for several days but not able to prove it, suppose polar ice on earth melt, would the days be longer? My friend said it was due to moment of inertia of the earth increase but I could not link it up.  Can anyone explain me properly this problem.


C# Windows Form - Apply filter to image normally but got NullReferenceException using Thread

I'm applying a filter to multiple images, and it works well but really slow. (NOTE: images, filter, filter_size, div are already loaded and assigned) for (int i = 0; i < 5; i++)     out[i] = MyFiltering((Bitmap)images[i], filter, filter_size, div);  Therefore, I tried to use a Thread for each image filtering to speed up as below: for (int i = 0; i < 5; i++) {     FilterThread[i] = new Thread(() => {out[i] = MyFiltering((Bitmap)images[i], filter, filter_size, div)}     FilterThread[i].IsBackground = true;     FilterThread[i].Start(); }  I've tried different ways (e.g., ThreadPool, Task.Factory.StartNew), but always get the NullReferenceException in MyFiltering for input img (i.e., images[i]), which should be definitely NOT NULL! Anyone has an idea?


How to find difference between 2 unix timestamps (milliseconds) and convert into human readable format

I want to find difference between current time and prev time given in milliseconds(unix time).  Example : difference(milliseconds) = (12345...)-(12345...)  now how to convert this milliseconds in to human readable format like 10 secs,40 minutes, 10 hours or 2 days or even H:M:S or DD-MM-YYYY H:M:S etc ?


Carnot Cycle with adiabats crossing on $pV$ diagram

So my Thermodynamics teacher said that on a  $pV$ diagram, you can get adiabats crossing for a Carnot cycle, even if all the possible thermodynamic states of the system can be represented on a  $pV$ diagram (2 dimensions). So this is NOT the case where a third state variable is needed to define the state of the system. However, since the Carnot cycle is reversible, the adiabats on the  $pV$ diagram are isentropic processes. So how can these adiabats cross? Because the point of intersection must have either one entropy or the other, because entropy is a state function. He said this can happen with things like water, which has the same density at a certain sub-zero temperature and then at a certain above-zero temperature, so at some point there is a maximum in one of the state variables. He said that on some occasions, the  $pV$ diagram is not useful in representing the processes because of this matter of lines crossing, and that another 2D diagram would be clearer. Well, how can the adiabats cross? What could produce this situation?


How is the Universe expanding faster than the speed of light?

I was watching a youtube video about the expansion of the universe. So the video said that the universe is expanding at a speed faster than the speed of light. I have 2 questions about that. My first question is doesn't this contradict einstein's theory of relativity that states nothing can travel faster than the speed of light.  please note that i did look at some other questions similar to this one but i couldnt find an answer to my question. My second question is where does the universe expand to. If the unviverse holds all matter then where does it expand to. If it expands to nothing there would be nothing to expand to right. Is the universe creating space? ps, please keep in mind i am only 13 so it would be great if you could keep your answers as simple as possible.


Which spells or abilities are affected by things that care about targeting?

Note: this is intended to be a canonical question about whether or not a spell or ability targets so there are multiple sub-questions.   Can Hexproof or Shroud save my creature from ? What about a  that was cast for it's Overload cost? Does shroud prevent me from using the Monstrosity ability of a creature, or from giving it more counters with Proliferate? Can I cast an Aura Enchantment on one of my creatures with Shroud, or an opponent's creature with Hexproof? Or can I use the Equip ability to attach an equipment to one of my creatures with Shroud? Will 's ability trigger when my opponent plays ? And will I have to sacrifice my  if my opponent casts ? Will Shroud or Hexproof prevent an opponent from choosing me with 's ability? Will Hexproof keep one of my creatures from being affected by ? If an Aura or Equipment is attached to a creature with Hexproof, does the Hexproof protect the attached permanent?


Achieve Damascus steel style with Cycles

so I'm modeling a katana, and I would like to give it a proper "Damascus" style to the blade, and I was wondering if it's possible to achieve this in a way that doesn't involve me opening GIMP/Photoshop.  The desired effect is this:   So far I got this material:  Ignore the red tint.  So my questions are:   How to "mask out" the black so I can control it, and apply the Principaled on top of let's say a brushed metal shader. Is there a way I can make the noise/musgrave/voronoi start in stripes and then go wavy? Maybe aWave texture and use a ramp to fade them?   Thanks for any input!


Is there a example of ring which is artin algebra but not artinian ring?

Every artin algebra is artinian ring. Is there an example that artinian ring but not artin algebra?


I'm trying to hook up a projector that only has an VGA input to my laptop that has only an HDMI output. I would like to avoid spending extra money on a HDMI to VGA converter box, is it possible to do the same with these two converters chained:  and ? Will that work?  I am trying to establish if this particular scenario (two converters chained) would work, the that this is marked of duplicate doesn't discuss this.


If $ 1 + \sqrt 2 + \sqrt 3 + \sqrt 6 = \sqrt{a+\sqrt{b+\sqrt{c+\sqrt{d}}}}$ for integer $a$, $b$, $c$, $d$, find $a+b+c+d$

Consider the following equation:   $$ 1 + \sqrt 2 + \sqrt 3 + \sqrt 6 = \sqrt{a+\sqrt{b+\sqrt{c+\sqrt{d}}}}$$   where $a$, $b$, $c$, $d$ are integers. Find $ a+b+c+d$


Troubleshoot issues with SPO - Office 365

In SharePoint on premises, we have correlation ID and ULS logs, we also have developer Dashboard. But how do we troubleshoot issues in SharePoint online.


how to deploy only the Commit - continuous integration?

I am facing an issue and am sure there must be very simple solution for this.Can anyone help me ?  I have bamboo server running which picks up stash rep where I have committed my code from Eclipse Force.com IDE. When I run the bamboo plan , it kind of deploys everything (all files from src) when I have committed only one component (say VF page). I modified mt package.xml to include only that VF page and nothing else. But still deployment runs across all 13k components.   I know I can remove all those components from my src folder and keep only VF page. SO that it deploys only that component. But is there any way , so that it picks up only the commit and not entire src folder ?  Any pointers helps greatly appreciated.


Monty Hall Problem: Reasoning Behind the Logic

I watched  from the MIT OpenCourseWare where the lecturer talks about the Monty Hall problem. He draws the decision tree and we find that actually you have a 2/3 chance of winning if you switch, and a 1/3 if you stick.  I understand the intuition, and the proof behind this (i.e. the decision tree).   However, what I dont understand is when a door is revealed, why doesn't the probability change from 1/3 to 1/2? Why is picking a door, then having one revealed, different from just having two doors and picking one at random?


Optimize Google Sheets to process/summarize large amounts of data

I have a Google Sheet where data is uploaded from a Google Form in one page and workers input data directly in another page. The data is combined into one table via scripts. I am trying to create a dashboard to monitor the data, and currently have several pivot tables that feed charts and formulas. There are currently ~7000 rows to process.  What are some ways to optimize the spreadsheet to handle thousands of rows of data? For example, is there a way to change the recalculation cycle to only refresh every 2-3 minutes? The only calculation settings I can find are in the "Spreadsheet Settings" menu and only affect the TODAY(), NOW(), and RAND() functions.  In , I asked specifically about whether pivot tables or the SORT(FILTER()) combo is faster in this context, but wanted to ask for more general help too.


Is it possible to mount on a PC an SD card that has been encrypted by an Android Marshmallow device?

I have a Samsung Galaxy S5 duos with stock Android Marshmallow, and I'm considering encrypting my SD card to prevent access to its contents in case I lose my phone. The main reason of not doing this is that I'm not sure if there's a way to mount an encrypted SD card on Windows (or other desktop OS's)   When I encrypt the SD card on my Samsung Galaxy S5, is it using a known implementation of encryption, or is it something that only works on Android (or perhaps Samsung) phones?   I do not want to use USB connection to my phone to access my SD card, it's terrible. Mounting the SD card is much easier and faster and less annoying.   EDIT: just to clarify, I am NOT talking about adoptable storage. I want a portable encrypted SD card that can both be read on PCs and Android phones (i.e. I want to be able to remove the SD card from my phone, plug it into my PC, provide a password to decrypt and read/write it like any other SD card)


How can I self-teach myself classical mechanics?

What I'm specifically looking for here are resources or maybe even sequences of books that take me from introductory level all the way up to kinda advanced level classical mechanics. I'm just kinda confused on where to start and where to learn from.


How to make the enemy only start pathfinding when player is within certian distance

Im using A* pathfinding and unity 2d. Also im very new and dont really know how to code well so if you can tell me the code it would be much appreciated. I figured out how to use A* but i dont want the enemy to constantly follow my player every where


How to show equinumerosity of  the powerset of $A$ and the set of functions from $A$ to $\{0,1\}$ without cardinal arithmetic?  Not homework, practice exercise.


Can I number a page from 1 to 9 as 01 to 09?

Is there a way of adding a 0 to page numbers (or any other counter, for that matter) from 1 to 9?   I wanted to number those pages as 01, 02,...,09, 10, 11,...  This is for design purposes only.


Where is network adapter state information stored in the registry?

Running netsh interface ipv4 show interfaces in cmd shows some network interface information, including the state (connected or disconnected). Is this information stored in the registry and, if so, where can I find it? I know IP addresses are found in subkeys of HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces (as answered ), but I'm not seeing state information there. I found the StaleAdapter value in subkeys of HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\DNSRegisteredAdapters, which updates on connection/disconnection. However, I doubt that this is really what I'm looking for, as there are less subkeys than there are network interfaces in the netsh output.


Temperature of the system stays constant even though it moves?

According to thermodynamics we were taught that temperature of a body is the measure of avg kinetic energy of the molecules which make up the body . Now if we consider an insulating box full of gas at stationary w.r.t an inertial frame of reference let s and tempertaure be t.Now if we change our frame in such a way that the box is in motion ,than the kinectic energy of the molecules also increase hence the temperature appear to be different but it is not so.(I know i somewhere made a mistake in defination of temperarure )


How do I find the child relationship name?

I'm using a SOQL to query the lookup relationships.  Primary Object: Opportunity  Secondary Object: Purchase__c.  From purchase__c we have a lookup to opportunity.  Field Name: Opportunity__c  Child Relationship Name: Purchases2  SOQL query:  for (Opportunity opp : [select Id, Name, (select id from Purchases2__r where Count__c>0) from Opportunity where Id IN :oppIds])    whats wrong with my query? getting error below:     If you are attempting to use a custom relationship, be sure to append the '__r' after the custom relationship name.


Is there a generally acknowledged "fine" line between the meanings of the two terms "statistics" and "data science"? If not, why is "data science" seen nearly everywhere? Just want to learn about the opinion from the active scholars so that I may not embarrass myself when it comes to the subject(s) nor mislead people thinking of another things when they are not intended.


Restrict a user from viewing other user's processes

Suppose there are two users : user1 & user2.  Now we know that if I give top -u user1, I can see only the process respective to user1.  But if I do top -u user2, I can see all the process running under user2.  Similar is the case with ps -f -U user1.  Is there a way to make ps & top restrict to only see the processes running under their Id & not others ?


I would like to write a "game", where you can place an obstacle (red), and then the black dot tries to avoid it, and get to the green target. I'm using a very easy way to avoid it, if the black dot is close to the red, it changes its direction, and moves for a while, then it moves forward to the green point.   How could I create a "smooth" path for the computer controlled "player"? Edit: Not the smoothness is the main point, but to avoid the red blocking "wall" and not to crash into it and then avoid it.  How could I implement some path finding algorithm if I just have basically 3 points? (And what would it make the things much more complicated, if you could place multiple obstacles?)


A few days ago I asked a question about the inadequate performance of the newfangled rendering of the math formula display.  It has disappeared.  What happened to it?


Expansion of the universe & laws of physics

Does the expansion of the universe have an effect on the laws of physics, or the constants used in physics? If we were to imagine the universe 40 billion years later, would the same laws still apply?


New question based on an existing question on Minimum and Maximum of N(0,1)

This question is an additional question to the given posted here:   Let $X, Y$ be independent $N(0,1)$ and let $M=Max(X,Y)$. In the previous problem, what was being asked was the covariance between $M$ and $m=Min(X,Y)$. My question is what if the only requirement is to find $E(M)$? Is it necessary to define $Min(X,Y)$ and use it to eventually solve for $E(M)$?


How to generate correlated test data that has Bernoulli, categorical, and continuous vectors (in R)?

I'm looking to generate a set of 5 random variables and enforce a dependence structure between them and onto a dependent variable $Y$.  I understand how to generate correlated random variables for multivariate normal, but not when mixing different types.  Below is a little more than I need, but I'm hoping someone can give me a general way of solving this problem...   $X_1$ and $X_2$ need to be highly correlated Bernoulli variables.  $X_3$ needs to take one of 5 categorical values, call them "A"..."E".  $X_4$ needs to be normal, and negatively correlated with $X_1$, $X_2$.  $X_5$ needs to approximate test scores from $0$ to $100$ with a high skew, so gamma probably.  $X_5$ needs to be positively correlated with $X_1$, $X_2$, $X_4$.   Each of these variables must impact a "success/occurrence" Bernoulli distributed variable $Y$.  How would I begin?  I would like to enforce correlation both between the values of $X$, and also between each $X$ and $Y$.  (The categorical correlations seem particularly confusing to me.)


Definition of continuous function in topological space

According to some notes, definition of continuous function is as below :  Definition 1.1 (Continuous Function) A function $f:X→Y$ is said to be continuous if the inverse image of every open subset of $Y$ is open in $X$.  And therefore we can say a function $f:X→Y$ have continuous inverse if the image of every open subset of $X$ is open in $Y$. Wouldn't be better if we define a function as continuous if it mapped every open set in $X$ to an open set in $Y$ (in other word ,exactly what we defined for continuous inverse) ? What is technical reason beyond this definition ?


Let $X$ be topological space, $K_{A}$ function defined with $ K_{A} (x) = 1, x \in A, K_{A} (x) = 0, x \in X\backslash A$. Prove that if $ K_{A} $ is continuous then $FrA =\emptyset$ ($FrA=ClA\backslash IntA$).  I tried by contradiction. Since $ClA= A \cup A^{'}$ I decided to separate proof in two cases. First case ($x \in (A^{'}\backslash A)$ ) I easily got contradiction, but on this second case ($x \in (A\backslash A^{'})$ ) I got stuck.


This is a double question: The correct answer will go to "How you do it in PHP" explaining if there is any advantage goes also counts if possible.  I'm just curious because I really don't know and I see it a lot in webpages.  Edit: I don't know the technical name, but for example here on Stackoverflow: "http://stackoverflow.com/posts/edit/522452" is what I mean as "folders" (a term previously used in the title of the question).


when i want to connect have this problem "error": "Internal Server Error", "message": "No message available",

@PostMapping("/signin")  public ResponseEntity<?> authenticateUser(@Valid @RequestBody LoginRequest loginRequest) {      System.out.println("a"+loginRequest.getUsername()+loginRequest.getPassword());     Authentication authentication = authenticationManager.authenticate(             new UsernamePasswordAuthenticationToken(loginRequest.getUsername(), loginRequest.getPassword()));     System.out.println("a"+loginRequest.getUsername()+loginRequest.getPassword());    // new RuntimeException("Error: cccccc is not found.");     SecurityContextHolder.getContext().setAuthentication(authentication);     String jwt = jwtUtils.generateJwtToken(authentication);    new RuntimeException("Error: cccccc is not found."+ jwt);     //    new RuntimeException("Error: cccccc is not found.");     UserDetailslmpl userDetails = (UserDetailslmpl) authentication.getPrincipal();     List<String> roles = userDetails.getAuthorities().stream()             .map(item -> item.getAuthority())             .collect(Collectors.toList());    // new RuntimeException("Error: aaaa is not found.");     return ResponseEntity.ok(new JwtResponse(jwt,             userDetails.getId(),             userDetails.getUsername(),             userDetails.getEmail(),             roles)); }


Suppose that $N$ pairs of socks are put in a washing machine, with each sock having one mate. If the washing machine randomly eats socks, and at the end of the wash returns a random number $K$ of socks where $0 \leq K \leq 2N$, where each $K$ is equally probable, what is the expected number of complete pairs of returned socks?  Just from working out the first few values of $N$, I conjecture that the answer is $N/3$, but I am not sure how to prove it for all values of $N$.  Just to be clear, this is the expected value for an infinite number of trials where each $K$ is equally probable, not the expected value for an infinite number of trials where $K$ is fixed, whereupon the answer is $\displaystyle{K \choose 2}/(2N-1)$.


Find expression for : $ S_n =\sum_{i=1}^{n} \frac{i}{i^4+i^2+1} $

I want to find a formula for the sum of this series using its general term. How to do it?  Series $$ S_n = \underbrace{1/3 + 2/21 + 3/91 + 4/273 + \cdots}_{n \text{ terms}} $$  General Term  $$ S_n = \sum_{i=1}^{n} \frac{i}{i^4+i^2+1} $$


Regarding number of degrees of freedom of a dynamical system (as well as it's relation to number of equations of motion)

I would like to know why in the context of vibrating systems, we define degrees of freedom in terms of number of independent coordinates (by coordinates I mean the numbers which specify the components of vectors) required to specify the motion instead of the configuration (configuration refers to just the positions and not velocities). Are these definitions equivalent because for motion, we are always concerned with the rate of change of each coordinate (describing the position or configuration) and thus motion also ends up involving same number of coordinates to describe the motion?  The book I am reading also mentions a line saying      On occasion, when internal forces are carried as unknowns, the number   of equations exceeds the number of degrees of freedom by the number of   unknown forces.   I am not able to see where would such a need arise; an example of this would be greatly appreciated.


20.04 cannot delete or write files in NTFS file system

I have a dual booted system. Since upgrading 18.04 to 20.04 beta I can no longer delete files or save files in the Windows file system. Delete and shift-delete seem to be disabled.


extrude and animate a polygon along path

Hello I have to make an animation with this shape, but i cant find out any tutorial to explain me the method to achieve the result I'm looking for. I would like to extrude and animate a square shaped polygon that follows the yellow arrow path so that it builds up the entire shape in red.  Thank you very much for your time.


Tried out Xubuntu via:  sudo apt-get install xubuntu-desktop  How do i go back to unity and delete everything xubuntu related?  Thanks.


he is coauthor of three books -- why is there no indefinite article in front of "coauthor" in this sentence?

Example:     Peter Gulutzan, MySQL AB Software Architect, worked with stored procedures for a different DBMS for several years. He is coauthor of three SQL books.   Question #1: I asked a friend of mine who is from the United States and he said that coauthor is absolutely fine with no article. But I don't understand why that's true. I'd use an indefinite article, if I had to write that sentence. So, why do you think there is no indefinite article in front of coauthor?  Question #2: Do think the following sentence would sound grammatically worse? If so, why do you think it would?     Peter Gulutzan, MySQL AB Software Architect, worked with stored procedures for a different DBMS for several years. He is a coauthor of three SQL books.


Prove the reciprocal of a function is integrable if it is bounded

Let $f(x)$ be Riemann integrable on $[a,b]$ and satisfy $\inf\{\left|f(x)\right|:a\le x \le b\}=d>0$.  How can we prove that $g(x)=\frac{1}{f(x)}$ is Riemann integrable?  I know from the statement that $f(x)\neq 0$ since its $\inf$ is $d>0$, so $g(x)$ is bounded on $[a,b]$ since $f(x)$ is bounded and there is no division by $0$.    Is there a relationship like $M(f)=m(g)$ and $m(f)=M(g)$, since $g(x)$ is the reciprocal?


Need to change this JQuery code to check for element existence prior to processing

I have the following code:              <script type="text/javascript">             $(function () {                 $('#js-news').ticker({                     speed: 0.10,                     htmlFeed: false,                     fadeInSpeed: 600,                     titleText: 'DASHBOARD ALERTS',                     direction: 'ltr',                     displayType: 'reveal',                     controls: false                 });             });         </script>   I would like to alter it such that it only fires if #js-news is present. In older IE V10 browsers I am getting the error: "Element does not exist in DOM", and the relevant pages do not have the js-news element. Newer browser seem to cope, but not IE7,8,9.  Thoughts on code alteration appreciated.  Thanks.


Should "Good Morning" always be used as the first greeting of the day?

Is it true that regardless of the time of the day, the first wish to a person must be Good morning? Even if I meet him in the afternoon?


Resource to find regular flights between given cities

Is there a search engine to find regular service flights between cities ? Given two cities, airline optional, I'd like to see a list of flight numbers and their departure/arrival times. Unlike regular searches, I'm not interested in prices/purchasing and I'd like to see all flights available even if the earliest departure has already past.    Context: A friend is flying into town today from Calgary, but I don't know when. I happen to know it's Air Canada so I found the routes and flight numbers on their website, but assuming I didn't, where would I find this information (besides asking her for the flight number obviously :) ?


Minimum and maximum of $y=\cos\theta(\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha})$

The minimum and maximum values of expression $y=\cos\theta(\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha})$ is:  My attempt is as follows:-  Attempt $1$:  $$y=\cos\theta\sin\theta+\sqrt{\sin^2\theta\cos^2\theta+\sin^2\alpha\cos^2\theta}$$ $$y=\dfrac{\sin2\theta}{2}+\sqrt{\dfrac{\sin^22\theta}{4}+\sin^2\theta\cos^2\theta}$$  Here the term $\cos^2\theta$ created the issue and I didn't find any way to proceed further.  Attempt $2$:  Rationalizing   $$y=\dfrac{\cos\theta\cdot\sin^2\alpha}{\sin\theta-\sqrt{\sin^2\theta+\sin^2\alpha}}$$ $$y=\dfrac{\sin^2\alpha}{\tan\theta-\sqrt{\tan^2\theta+\sin^2\alpha\sec^2\theta}}$$  Here I was not able to comprehend how to get minimum and maximum value.  Attempt 3:  $$\dfrac{dy}{dx}=-\sin\theta(\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha})+\cos\theta\left(\cos\theta+\dfrac{1}{2\sqrt{\sin^2\theta+\sin^2\alpha}}\cdot2\sin\theta\cos\theta\right)$$  $$\dfrac{dy}{dx}=-\sin\theta(\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha})+\cos^2\theta\cdot\dfrac{\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha}}{\sqrt{\sin^2\theta+\sin^2\alpha}}$$  $$\dfrac{dy}{dx}=(\sin\theta+\sqrt{\sin^2\theta+\sin^2\alpha})\left(-\sin\theta+\dfrac{\cos^2\theta}{\sqrt{\sin^2\theta+\sin^2\alpha}}\right)$$  Now from here it will be very difficult to decide about the maximum and minimum value.   Any inputs?


A proof for $\nabla |u|^p = p\ \text{sgn}(u)|u|^{p-1}\nabla u$.

I believe the formula  $$\nabla |u|^p = p\ \text{sgn}(u)|u|^{p-1}\nabla u $$  to be true for $u\in W^{1,p}(\Omega)$, where $\Omega$ is an open domain with nice boundary, but failed to find a good reference for this.  I am sorry if this has been asked already.  The usual assumption that I usually see regarding the chain rule for Sobolev functions, i.e. $$ \nabla F(u) = F'(u)\nabla u, $$ is that $F\in C^1$ with bounded derivative (or perhaps a Lipschitz function). I want $F(t)=|t|^p$, which doesn't satisfy that assumption.  My idea of the proof goes as follow: I'd like to mimic the proof of the case $p=1$ so first we show a similar result for $$ F_\varepsilon(t) = (\varepsilon^2 + t^2)^{p/2} $$ by approximation with $F_\varepsilon(u_n)$, where $u_n\to u$ in $W^{1,p}$ and $u_n\in C_c^\infty(\Omega)$. Then we take $\varepsilon \to 0$ to approximate $|\cdot|^p$. While the usual argument using the Dominated Convergence Theorem wouldn't work, I think Vitali Convergence Theorem might do the trick.     Does anyone know a reference to this result? Also, if the formula doesn't hold in general spaces (i.e. $u\notin W^{1,p}$) then does anyone have a counterexample?   I have seen the proofs of the cases $p=1,2$. Finding a reference for a general $p\in [1,\infty)$ turns out to be a lot harder than I anticipated.


Should buttons be illuminated, or darkened, upon hover?

To most, this question might feel subjective... but there's really more than just opinion involved here.  If you hover your hand over something in real life, most times a subtle shadow will appear above the object. Mimicking that same idea in the form of user-interface / experience could be more intuitive or natural... or not if the user perceives technology as something totally separate from real life.  An example of the two:   So again, what is more intuitive to the user, a button that is illuminated upon hover, or darkened upon hover? And why?


What is the relationship between exponentials and complex coordinates?

I find it hard to grasp my head around the fact that $$ e^{ai} $$ gives a rotation around the unit circle. I'm aware that $$ e^{ai} = \cos(a) + i\sin(a) $$ but I can not for the life of me give this equation meaning. What is the relationship between Eulers number and circles?


Set of functions from $\mathbb{N}$ to $\mathbb{R}$

How do I prove that the Cardinality of the set of functions from Natural Numbers to Real Numbers is equal to the power set of Real Numbers?


Is any version of Ubuntu compatible with Lenovo R60?

I have a legacy Lenovo R60 laptop running an Intel Core Solo T3100 (1.67MHz) processor currently running Windows XP (192mb RAM / 40GB HDD). My goal is to try and run Ubuntu on it using a pen-drive, so that machine response is faster and I can free up some space on it for other purposes. Would any particular version of Ubuntu only, work? I would love any tips that a Linux noob can use, and a link to the exact version of Ubuntu to be downloaded would be really appreciated!


Prove that $\mathbb{|Q|} = \mathbb{|Q \times Q|} $

This question exists, but both cases have a specific answer for the OP's situation. I do not know how to prove that $\mathbb{Q}$ is countable.  Questions I am referring to:  and


Salesforce 2GP Package Install, Post install script

Created a 2GP managed package. After the package installs - a post install script will queue a future method call. The future method will need to access StaticResource object (SOQL query)- download a file in blob format using PageReference class and do other things. The future method class is marked with "WITH SHARING" keyword. After the package is installed; the future method runs and we get this error in the future method: sObject type 'StaticResource' is not supported. Should I be using "WITHOUT SHARING" in future method class. The package installer is System Administrator with access to all standard/custom objects. What could be going wrong here? If I run the future method in sandbox environment from DevConsole - everything works. Thank you.


Why is "Processor microcode for Intel CPU" is installed even though I don't have an Intel CPU?

In one of the update prompts I get this    This leaves me wondering, why does Ubuntu install it in the first place if it should be of no use? (my CPU is made by AMD) Is it just to have it ready whenever I boot the system on a totally different hardware?


This is my first question, so I’m sorry if I made mistakes.    $\left(\begin{array}{ccccc}1&1&1&\cdots&1\\2&2^2&2^3&\cdots&2^n\\3&3^2&3^3&\cdots&3^n\\\vdots&\vdots&\vdots&\ddots&\vdots\\n&n^2&n^3&\cdots&n^n\end{array}\right)$    In order to solve the above inverse matrix,  I tried to solve the below liner simultaneous equations in n-th unknowns.    $kx_1+k^2x_2+\cdots+k^nx_n=1+2^{n-1}+\cdots+k^{n-1}$ $k=1,2,\cdots,n$  Inductively, I know the solution of the liner simultaneous equations.  $x_k=\frac{B_{n-k}}{n-k} {n-1 \choose n-k-1} (1≦k<n-1)$ $x_{n-1}=\frac{1}{2}$ $x_n=\frac{1}{n}$  But even though I solved the solutions of the equations, I have no ideas how to use it.    I thought Vandermonde’s déterminant may be effective, but I have no ideas how to use it.


How does oscillator frequency stability affect timing?

If, for example, a crystal oscillator is specified as +/- 100ppm what does that mean? That the exact frequency is uncertain to that degree, or that the frequency varies by that degree over normal operation? Also, does that automatically imply that any timing based on it is inaccurate to the same degree?


How can I resize a partition with Disk Utility?

I have 2 partitions, I reduced the size of one and want to expand the other to fill the now available space.   How do I expand the Lion Partition into the empty grey space beneath Macintosh HD partition?


Can I rename files within a folder with the name of the parent folder?

this is a unique situation, which can be better explained with an example  Example 1 let's say I have a folder called A, B.mkv and C.srt are two files in the folder, I want to rename these files to A.mkv and A.srt.  practical example would be, a folder called American Sniper (2014) and American.Sniper.2014.1080p.BluRay.x264.YIFY.mkv and American.Sniper.2014.Subtitle.BluRay.ShaAnig.srt are two files in the folder, want to rename these files to American Sniper (2014).mkv and American Sniper (2014).srt  Example 2  This Should be recursive let's say I have a folder called A, B and C are two Sub-folders in the folder A. contents of B and C are like following    Should get converted to    Even when I run the algorithm/script/command on folder A  3rd thing that it should do is, It should Ignore hidden files  example    should result in    lastly it should work on multiple folders at a time


Let $H$ be a subgroup of $G$ and let $a$ and $b$ belong to $G$. Then $aH=bH$ or $aH \bigcap bH =\emptyset$

Let $H$ be a subgroup of $G$ and let $a$ and $b$ belong to $G$. Then :  $aH=bH$ or $aH \bigcap bH =\emptyset$ ...... (1)  Gallian gives the following proof which i have a little trouble understanding :  By a previous result, we have : $aH = bH $ if and only if $a \in bH$ ....(2)  It says $(1) $ follows directly from $(2)$ for if there is an element c in $aH \bigcap bH$, then $cH = aH $ and $cH = bH$ .  I don't understand the above statement, so i have made the following attempt :   Attempt: If $aH \neq bH$ , then $a \notin bH$ by $(2)$  So , if $a \notin bH$, what can i say about $aH \bigcap bH$?   Thank you for the help


Compute $\lim\limits_{n \to \infty} {\frac{1 \cdot 3 \cdot 5 \cdots(2n - 1)}{2 \cdot 4 \cdot 6 \cdots (2n)}}$

EDIT: @Holo has kindly pointed out that my concept of ln rules used in this question is wrong. However, the intuition behind using the tangent of a curve to find the sum to infinity of a series still stands. Therefore, I won't be editing the post.  I tried expanding out the equation from the question and got $${a_{n}} = \frac{1}{2} .\frac{3}{4} . \frac{5}{6} ...\frac{2n -1}{2n}$$  I then tried taking the ln of the equation which works out to $$\ln(1 - \frac{1}{2}) + \ln(1 - \frac{1}{4}) + ...$$  Here is my question. I used the rules of ln functions and took $ln(\frac{1}{1/2}) + ln(\frac{1}{\frac{1}{4}})$ + ...  Since ln(1) is 0, shouldn't the limit work out to 0 as n tends to infinity? Then $$ln(L) = 0, where L = limit$$ $$L = e^0$$ $$L = 1$$   However, the limit is actually 0, and my tutor used a method which I couldn't understand as he tried approximating the function $y = ln(x)$ to $y = x - 1$, as he says that the linear equation is actually a tangent to the ln curve. Could someone please explain this intuition behind it? He differentiated the equation, and since the curve cuts the x-axis at x = 1, he got the linear curve $y = x - 1$.  He did mention that the linear equation is just an approximation, but said such an approximation would be more than sufficient.


When must the wizard choose to overchannel?

The Evocation specialist wizard's overchannel ability says:     When you cast a wizard spell of 5th level or lower that deals damage, you can deal maximum damage with your spell.   Does the "that deals damage" clause mean the wizard can decide to overchannel once they are sure the spell is going to deal some damage?  i.e., that it is not counterspelled or evaded by a successful save, etc.   (This would be similar to paladins being able to choose to apply smite damage after they know they have hit, so this kind of post-hoc add on is not unprecedented.)