If I stand 10 feet away from a subject and I want a close up shot, I can either zoom in or I can physically move the camera as close as possible to the subject. Which one is a better practice, or is it the photographer's discretion?

This is another perspective distortion question. I understand that perspective distortion is primarily a function of capture and viewing distance, but I am still working on fully understanding the causes of the "flattening" of scenes that is credited to telephoto lenses.  This seems to refer to our ability to discern the differences in size attributable to differences in distance from the lens for subjects beyond a certain distance from the lens. If this is correct, then is it just that with the longer distance from the subject when using a telephoto lens, this compression happens closer to the foreground, rather than in the mid- or background with a wide lens?  Is it fair to say that the compression effect occurs at a certain distance from the photographer regardless of lens, but the field of view influences how close to the foreground this effect takes place? Can you share any information to help people like me understand this?


I am going to Canada from Minnesota, USA 7/11/20 and returning 7/18/20 to MN. My passport expires 8/16/20. Will Canada accept this passport?

I am from Trinidad, my Trinidadian passport and Canadian visa both expire in July. Can I still travel to Canada in April, using both documents?


Curious to know if I did something wrong in flagging this question as I see the flag is disputed?  The answer in question is very clearly not an answer to the question at all - not even remotely related to it. It looks just weird - like someone meant to answer a different question.  I've never seen a disputed flag, and I just read a few meta questions about disputed flags - and the answers covered justification of bad answers, wrong answers etc... but I can't see an answer covering the scenario of a total non-sequitur that isn't just a valid "Not an answer".  The answer in question is here:    It seems to fall into the "not an answer" category as described here:

In my flagging summary under the statistics, there is 1 flag listed as "disputed".  This is the first time I've ever seen a disputed flag in my summary, so I'm just curious, what is a disputed flag? How would you even dispute a flag? Is this the same as voting a flag as invalid?


NOTE: I am really not very good at Multithreaded programming, but my current project has me doing it so I am trying to get my head around what is thread safe and what is not.  I was reading one of Eric Lippert's .  He says this is what really happens:   x is evaluated to produce the variable the value of the variable is copied to a temporary location the temporary value is incremented to produce a new value (not overwriting the temporary!) the new value is stored in the variable the result of the operation is the new value   This got me to thinking, what if two threads where calling ++i?  If the first thread is at step 3 when the second thread is on step 2.  (Meaning what if the second thread copies the value off to the temp location before the first thread stores the new value in the variable?)  If that happens then it would seem that both threads would only increment i once instead of twice.  (Unless the whole thing is in a lock.)

Inspired by this question:   Take the following psuedo code:  class test {    int _counter;    void Increment()    {      _counter++;    }  }   Would this be considered thread safe on an x86 architechure? Further more are the Inc / Dec assembly instructions thread safe?


I am getting a crash (on android 7 only) when setExacctAndAllowWhileIdle in a function where I am create new alarm. I have no idea what is wrong here. And how to fix this crash.  This is my code and getting crash when calling   AlarmManagerCompat.setExacctAndAllowWhileIdle  AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);     if (alarmManager != null) {         final long triggerAt = System.currentTimeMillis() + interval;         AlarmManagerCompat.setExactAndAllowWhileIdle(alarmManager, AlarmManager.RTC_WAKEUP,                 triggerAt, pendingIntent);     }   This is the crash report i am getting:  Caused by java.lang.NullPointerException Attempt to invoke virtual method 'int com.android.server.AlarmManagerService$Batch.size()' on a null object reference android.os.Parcel.readException (Parcel.java:1714) android.os.Parcel.readException (Parcel.java:1661) android.app.IAlarmManager$Stub$Proxy.set (IAlarmManager.java:246) android.app.AlarmManager.setImpl (AlarmManager.java:680) android.app.AlarmManager.setExactAndAllowWhileIdle (AlarmManager.java:893) androidx.core.app.AlarmManagerCompat.setExactAndAllowWhileIdle (AlarmManagerCompat.java:223) **com.mokapos.receiver.AlarmReceiver.setNewAlarm (AlarmReceiver.java:276) com.mokapos.receiver.AlarmReceiver.initServices (AlarmReceiver.java:203) com.mokapos.receiver.AlarmReceiver.onReceive (AlarmReceiver.java:196)** android.app.ActivityThread.handleReceiver (ActivityThread.java:3363) android.app.ActivityThread.-wrap18 (ActivityThread.java) android.app.ActivityThread$H.handleMessage (ActivityThread.java:1800) android.os.Handler.dispatchMessage (Handler.java:110) android.os.Looper.loop (Looper.java:232) android.app.ActivityThread.main (ActivityThread.java:6802) java.lang.reflect.Method.invoke (Method.java) com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1103) com.android.internal.os.ZygoteInit.main (ZygoteInit.java:964)

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I have an older Xbox 360 with Kinect but need to work out how big the hard drive is. I no longer have the original box. Can anyone tell me how to do this please?

I'm buying a Xbox 360 console off of Craigslist and the seller doesn't know the HDD size. How do we tell?


Analysing data from a past experiment I found that size of animals and a level of serum biomarker were associated with time to death when considered separately. Though when combining them in a cox model both the variable lost significance. How should I interpret and report this? Is it correct (and also relevant in scientific terms) to affirm that univariable association is lost when analysing both variables in a multivariable cox model?

When I analyze my variables in two separate (univariate) logistic regression models, I get the following:  Predictor 1:    B= 1.049,    SE=.352,    Exp(B)=2.85,    95% CI=(1.43, 5.69),    p=.003    Constant:    B=-0.434,    SE=.217,    Exp(B)=0.65,                            p=.046  Predictor 2:    B= 1.379,    SE=.386,    Exp(B)=3.97,    95% CI=(1.86, 8.47),    p<.001    Constant:    B=-0.447,    SE=.205,    Exp(B)=0.64,                            p=.029   but when I enter them into a single multiple logistic regression model, I get:  Predictor 1:    B= 0.556,    SE=.406,    Exp(B)=1.74,    95% CI=(0.79, 3.86),    p=.171 Predictor 2:    B= 1.094,    SE=.436,    Exp(B)=2.99,    95% CI=(1.27, 7.02),    p=.012    Constant:    B=-0.574,    SE=.227,    Exp(B)=0.56,                            p=.012   Both predictors are dichotomous (categorical). I have checked for multicollinearity.  I am not sure if I have given enough info, but I cannot understand why predictor 1 has gone from being significant to non-significant and why the odds ratios are so different in the multiple regression model. Can anyone provide a basic explanation of what is going on?


How do I tell MS Excel to use the contents from one cell if data exists (this data can be positive negative or zero).  If the data does not exist in said cell, use contents from another cell?

I have an Excel 2010 workbook that contains a number of individual worksheets. The cells on one of the sheets are linked to individual cells on two other worksheets in the same workbook.  I'm using a direct cell reference that essentially says that whatever value is entered into a particular cell on one sheet also populates cells on two other sheets.  I used the (=) function with the cell reference to accomplish this.  The issue I'm running into is that, even when the primary cell is left blank, the cells that populate from that primary cell will display 0, rather than remaining blank themselves.  I want the subordinate cells to remain blank if the primary cell they're linked to is blank.


I am using Ubuntu 20.04 LTS. When I use: sudo apt-get update  sudo apt-get upgrade  in the terminal, my software repository is updated, and the softwares are upgraded by some download. However, when I go to "Software Updater", there are some security updates present, namely: Generic Linux kernel header, Generic Linux kernel image, etc. (almost worth ~75 MB). I got confused because these security updates were not downloaded and installed when I ran: sudo apt-get upgrade  Why is it so? Should they be downloaded? Should I also enable (tick) Canonical Partners repository in Software & Updates > Other Software to get security updates?

I was wondering why upgrade sometimes doesn't want to upgrade certain parts of the system, while dist-upgrade does. Here's an example after running apt-get upgrade:  apt-get upgrade:  rimmer@rimmer-Lenovo-IdeaPad-S10-2:~$ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done The following packages have been kept back:   linux-generic linux-headers-generic linux-image-generic 0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.   versus apt-get dist-upgrade:  rimmer@rimmer-Lenovo-IdeaPad-S10-2:~$ sudo apt-get dist-upgrade Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done The following NEW packages will be installed:   linux-headers-3.0.0-13 linux-headers-3.0.0-13-generic   linux-image-3.0.0-13-generic The following packages will be upgraded:   linux-generic linux-headers-generic linux-image-generic 3 upgraded, 3 newly installed, 0 to remove and 0 not upgraded. Need to get 48.5 MB of archives. After this operation, 215 MB of additional disk space will be used. Do you want to continue [Y/n]?   In other words, why can't this be performed by upgrade?


I am an American who studied at a Latvian university in the previous fall semester.  I had planned to stay almost an academic year, so the company that organized my trip and partnered with the university in Latvia told me that I needn't worry about the 90 day limit, that they would register me for a temporary residence permit so that I could stay in Latvia longer than 90 days.  Despite the fact that I gave them all the documentation they requested for this, they apparently forgot to do it.  Anyway, I left Latvia to spend time in Moscow during the winter holiday and, naturally, was denied re-entry on the basis that I had already significantly overstayed.  I wasn't fined at the Latvian border.  The border guard simply told me I would be able to return if I stayed away for 90 days, no penalty, just a warning and a document explaining the 90/180 day rule.  I currently have tickets to fly back to America on May 3rd from Moscow to Riga and then Frankfurt.  I entered Schengen August 28th and left for Russia January 12th.  I was denied re-entry February 7th.  Does the entry refusal affect the 180 day period in some way?  Am I at risk of a fine for the overstay if someone notices in, say, Frankfurt?

According to law, what are the consequences of a US citizen overstaying a Schengen visa?  In practice, how likely is one to be penalized for overstaying by a day, 10 days, and a month?  Are there countries that are more likely to enforce the rules on departure?


Here is what I am trying to do but not exactly sure how to make this work. I have 3 sets of variables and I want to output all combinations of those 3 sets and output in a format that maintains the order of the variables like this:  list_of_vars = [var1, var2, var3]   The variables would look something like this:  var1 = [1, 2, 3] var2 = ["foo", "bar", "foo2"] var3 = ["a", "b", "c"]   The final output should look like this.  final_list_of_vars = [[1, "foo", a], [1, "bar", a], .......]

How can I get the Cartesian product (every possible combination of values) from a group of lists?  Input:   somelists = [    [1, 2, 3],    ['a', 'b'],    [4, 5] ]   Desired output:  [(1, 'a', 4), (1, 'a', 5), (1, 'b', 4), (1, 'b', 5), (2, 'a', 4), (2, 'a', 5) ...]


Please help, my usb flash drive just said it has no media, and i had all my documents, media and personal file i tried using chkdsk Minitools, and recovery but failed, how can i do The recovery if it says NO MEDIA  and keep complaining for no media And if attempted to open the drive it says Please insert a drive to USB (G:) and to disappointed all recovery options failed, disk manager says no media, i reinstall driver, uninstalled driver and reinstall driver, nothing worked is there a super recovery option or software? a command?, or tool to recover instense data loss NOTE: the USB flash drive did not fell or loosen connection to the media in it Please Help this data recovery

I have a USB flash drive which is no longer recognized by my computer. Windows Disk Management and DiskPart report No Media with no storage space (0 bytes) on the drive and I cannot partition or format the drive:     If the drive appears in Windows Explorer, trying to access it returns an error message indicating that there is no disk inserted, such as the following:     Please insert a disk into drive X:.   Various disk partitioning and data recovery utilities don't recognize the drive or only give a generic name for the drive and cannot access the contents of the drive.  What can I do? How do I recover data from the drive?     This question comes up often and the answers are usually the same. This post is meant to provide a definitive, canonical answer for this problem. Feel free to edit the answer to add additional details.


This is a much-simplified version of my program but has the same idea: def calc():    x=1    y=2    z=6 def output():    final=x+y+z  how can I use the return values in the first function to be used in the second?

The canonical way to return multiple values in languages that support it is often . Option: Using a tuple Consider this trivial example: def f(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return (y0, y1, y2)  However, this quickly gets problematic as the number of values returned increases. What if you want to return four or five values? Sure, you could keep tupling them, but it gets easy to forget which value is where. It's also rather ugly to unpack them wherever you want to receive them. Option: Using a dictionary The next logical step seems to be to introduce some sort of 'record notation'. In Python, the obvious way to do this is by means of a dict. Consider the following: def g(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return {'y0': y0, 'y1': y1 ,'y2': y2}  (Just to be clear, y0, y1, and y2 are just meant as abstract identifiers. As pointed out, in practice you'd use meaningful identifiers.) Now, we have a mechanism whereby we can project out a particular member of the returned object. For example, result['y0']  Option: Using a class However, there is another option. We could instead return a specialized structure. I've framed this in the context of Python, but I'm sure it applies to other languages as well. Indeed, if you were working in C this might very well be your only option. Here goes: class ReturnValue:   def __init__(self, y0, y1, y2):      self.y0 = y0      self.y1 = y1      self.y2 = y2  def g(x):   y0 = x + 1   y1 = x * 3   y2 = y0 ** y3   return ReturnValue(y0, y1, y2)  In Python the previous two are perhaps very similar in terms of plumbing - after all { y0, y1, y2 } just end up being entries in the internal __dict__ of the ReturnValue. There is one additional feature provided by Python though for tiny objects, the __slots__ attribute. The class could be expressed as: class ReturnValue(object):   __slots__ = ["y0", "y1", "y2"]   def __init__(self, y0, y1, y2):      self.y0 = y0      self.y1 = y1      self.y2 = y2  From the :  The __slots__ declaration takes a sequence of instance variables and reserves just enough space in each instance to hold a value for each variable. Space is saved because __dict__ is not created for each instance.  Option: Using a  (Python 3.7+) Using Python 3.7's new dataclasses, return a class with automatically added special methods, typing and other useful tools: @dataclass class Returnvalue:     y0: int     y1: float     y3: int  def total_cost(x):     y0 = x + 1     y1 = x * 3     y2 = y0 ** y3     return ReturnValue(y0, y1, y2)  Option: Using a list Another suggestion which I'd overlooked comes from Bill the Lizard: def h(x):   result = [x + 1]   result.append(x * 3)   result.append(y0 ** y3)   return result  This is my least favorite method though. I suppose I'm tainted by exposure to Haskell, but the idea of mixed-type lists has always felt uncomfortable to me. In this particular example the list is -not- mixed type, but it conceivably could be. A list used in this way really doesn't gain anything with respect to the tuple as far as I can tell. The only real difference between lists and tuples in Python is that lists are , whereas tuples are not. I personally tend to carry over the conventions from functional programming: use lists for any number of elements of the same type, and tuples for a fixed number of elements of predetermined types. Question After the lengthy preamble, comes the inevitable question. Which method (do you think) is best?


I'm attempting to parse a String into a double with Double.parseDouble();, however I'm getting the following error:   Exception in thread "main"  35.5 java.lang.NullPointerException     at Caluclator/userInput.Calculation.addMinus(Calculation.java:57)     at Caluclator/userInput.Calculation.parse(Calculation.java:28)     at Caluclator/userInput.Input.main(Input.java:12)   I cant find where I'm going wrong.  package userInput;  public class Calculation {     public Double answer;      public  Calculation() {         }      //Splitting string for      public static Double parse(String input) {         String[] operator = new String[20];         String[] delimiter = input.split("\\+|-");         Integer counter = 0;          //this searches to see if there is an operator         for(Integer i = 0; i < input.length(); i++) {             char c = input.charAt(i);             if(c == '+'||c == '-'){                 operator[counter] = Character.toString(c);                 counter++;             }          }         delimiter = multDiv(delimiter);         for(String element: delimiter) {             System.out.println(element);         }         return addMinus(delimiter,operator,counter);//ERROR     }       //Multiplies the numbers     public static String[] multDiv (String[] delimiter) {         for(Integer y = 0; y < delimiter.length ; y++) {//iterates through elements in delimiter              for(Integer i = 0; i < delimiter[y].length(); i++) {//iterates through chars in element string                 if(delimiter[y].charAt(i) == '*') {                     String[] nums = delimiter[y].split("\\*");                     delimiter[y]= String.valueOf(Double.parseDouble(nums[0])*Double.parseDouble(nums[1]));                 }                 else if(delimiter[y].charAt(i) == '/') {                     String[] nums = delimiter[y].split("/");                     delimiter[y] =String.valueOf(Double.parseDouble(nums[0])/Double.parseDouble(nums[1]));                 }              }         }     return delimiter;     }  /////*****SEARCHES FOR ADDS OR SUBTRACTS THE NUMBERS *****////     public static Double addMinus(String[] numbers, String[] symbols, Integer counter) {         double answ = Double.parseDouble(numbers[0]);             Integer x = 1;              for(Integer i = 0; i < symbols.length; i++) {                 if(symbols[i].contentEquals("-")) {//ERROR                     double num = Double.parseDouble(numbers[x]);                     answ = answ - num;                     System.out.println(" "+answ);                 }                 else if(symbols[i].contentEquals("+")) {                     double num = Double.parseDouble(numbers[x]);                     answ = answ + num ;                     System.out.println(" "+answ);                 }                 x++;             }             System.out.println(answ);     return answ;     }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I've got a link I want to appear on my page,   add another   But it doesn't look like a link unless I add an href attribute. I'm going to be using jquery to add a .click() event to it, so it doesn't really need anything else.  What's the best value to href to? #? javascript:void(0)? My concern is if someone clicks it before the .click() event gets added or something. # will scroll them to the top of the page, void(0) looks kinda nasty and isn't informative if they look at the address bar...

I have seen the following methods of putting JavaScript code in an  tag:  function DoSomething() { ... return false; }    link link link link   I understand the idea of trying to put a valid URL instead of just JavaScript code, just in case the user doesn't have JavaScript enabled. But for the purpose of this discussion, I need to assume JavaScript is enabled (they can't login without it).  I personally like option 2 as it allows you to see what's going to be run–especially useful when debuging where there are parameters being passed to the function. I have used it quite a bit and haven't found browser issues.  I have read that people recommend 4, because it gives the user a real link to follow, but really, # isn't "real". It will go absolutely no where.  Is there one that isn't support or is really bad, when you know the user has JavaScript enabled?  Related question: .


How do I get the path to a resource in the model? I need to store it in the database and would like the same url as you get from resourcename_path(resource)

Say I have a Rails Model called Thing. Thing has a url attribute that can optionally be set to a URL somewhere on the Internet. In view code, I need logic that does the following:  <% if thing.url.blank? %> <%= link_to('Text', thing_path(thing)) %> <% else %> <%= link_to('Text', thing.url) %> <% end %>   This conditional logic in the view is ugly. Of course, I could build a helper function, which would change the view to this:  <%= thing_link('Text', thing) %>   That solves the verbosity problem, but I would really prefer having the functionality in the model itself. In which case, the view code would be:  <%= link_to('Text', thing.link) %>   This, obviously, would require a link method on the model. Here's what it would need to contain:  def link   (self.url.blank?) ? thing_path(self) : self.url end   To the point of the question, thing_path() is an undefined method inside Model code. I'm assuming it's possible to "pull in" some helper methods into the model, but how? And is there a real reason that routing only operates at the controller and view layers of the app? I can think of lots of cases where model code may need to deal with URLs (integrating with external systems, etc).


Can somebody please explain in detail what is entropy not a definition like its measure of disorderness. A complete  introduction from basics to what parameters it depends on as a thermodynamics point of view.

On , change in  is defined as the amount of energy dispersed divided by the absolute temperature. But I want to know: What is the definition of entropy? , entropy is defined as average heat capacity averaged over the specific temperature. But I couldn't understand that definition of entropy:  $\Delta S$ = $S_\textrm{final} - S_\textrm{initial}$. What is entropy initially (is there any dispersal of energy initially)? Please give the definition of entropy and not its change.  To clarify, I'm interested in the definition of entropy in terms of temperature, not in terms of microstates, but would appreciate explanation from both perspectives.


I want to calculate $\langle p_x\rangle$ and $\langle p_x^2\rangle$ for ground state electron in $\rm H$ atom. Radial function $$ \psi(r)=Ae^{-r/a} $$ Momentum operator in 3D: $$ \hat{\vec p}=\frac{\hbar}{i}\left(\frac{\partial}{\partial x},\frac{\partial}{\partial y},\frac{\partial}{\partial z}\right)=\frac{\hbar}{i}\nabla $$ Momentum operator 1D: \begin{align} \hat{p}_{x} & =\frac{\hbar}{i}\frac{d}{dx} \\ \langle p_x\rangle & =\int_V \psi^*(r)*\hat{p}_{x}*\psi(r) dV \end{align} Intuitively, $\langle p_x\rangle=0$ but how do I calculate it? Should I change the operator for one expressed in spherical coordinates or something else? And for $\langle p_x^2\rangle$ I would just square the momentum operator and use it instead.

I have been reading through this  of the ground state energy of hydrogen  and others like it. In this one it says it is using the uncertainty principal but then proceeded to use the following: $$pr=\hbar$$ But why is it not using: $$pr=\frac{\hbar}{2}$$ which is more in line with the uncertainty principle and what comes earlier in the derivation.


I'm making a 3D realistic eye on Blender, I started by an already pre-made file, and it came with a transparent material/layer that works like glossynes, still it doesn't apply to the texture on the background (the pupil). How can I make this model look better by making it reflect or 'shine'?  This is my actual project:    Everything is fine, but I want it to look like this:

O.k. I'm back and now i need to know how to make a metallic material in Blender Internal. The last question was for cycles and that fixed my problem, but Blender Internal doesn't have a Glossy BSDF. How do I get a glossy/metallic material in BI?


On the lower traffic SEs I frequent, it seems that occasionally an asker will accept an answer without upvoting it.  I am wondering if this is intentionally allowed (on the site's part) for a specific reason.  Something about seeing a question with no upvotes, a single answer with no upvotes and an accepted flag rankles me.    It seems like accepting an answer should automagically upvote it once, but I may be missing a reason for that not being the case.

Is there ever a case where you would want to accept an answer, but not upvote it?  I can't think of a single situation where this would be the case.. So would it not make sense to have the "Accept" button upvote the answer too?


simple question, I would like to know that is the best solution for cleaning my mesh?   Maybe the knife?

I need to change these polygons into a mesh with the same amounts of edges going the opposite way so I can end up with a mesh that I can curve edges upward and indent the heel and ball of foot area downward, sort of making it look ergonomic. Subdivide adds an diagonal edge but also vastly increases the edges where I already have enough. Suggestions?


Trying to use Regex to extract the repository name and pull request number from a url.   const paragraph = 'https://github.com/johndoe/awesome-repo/pull/12'; const regex = /https:\/\/github.com\/johndoe\/([a-zA-Z]+-[a-zA-Z]+)\/pull\/(\d+)/gm; const found = paragraph.match(regex);  console.log(found); // expected output: Array ["awesome-repo", "12"]    But the response is just the entire url > Array ["https://github.com/johndoe/awesome-repo/pull/12"] Any help would be appreciated

I want to match a portion of a string using a  and then access that parenthesized substring:  var myString = "something format_abc"; // I want "abc"  var arr = /(?:^|\s)format_(.*?)(?:\s|$)/.exec(myString);  console.log(arr);     // Prints: [" format_abc", "abc"] .. so far so good. console.log(arr[1]);  // Prints: undefined  (???) console.log(arr[0]);  // Prints: format_undefined (!!!)   What am I doing wrong?    I've discovered that there was nothing wrong with the regular expression code above: the actual string which I was testing against was this:  "date format_%A"   Reporting that "%A" is undefined seems a very strange behaviour, but it is not directly related to this question, so I've opened a new one, .    The issue was that console.log takes its parameters like a printf statement, and since the string I was logging ("%A") had a special value, it was trying to find the value of the next parameter.


What is the appropriate name for a person who exhibits the behavior described below?  A person who speaks in a Confidently informed manner (about a technical process or procedure for example) however they are actually imparting incorrect information and are apparently oblivious of their actions.

What's a phrase that describes a unfounded tendency of a person to think that he or she is smarter or possesses more skill than average in a competitive environment such as the stock market or say, the casino, and as a consequence is entitled to great financial gain at the expense of others, although the same belief is more likely to instead cause him/her to lose badly?


I am completely confused about this one. I know that a singular matrix is a matrix that does not have an inverse  I also know that I can find the eigenvalues of a matrix by finding the determinant of $A - yI$ so i guess i have to solve $A-0I$ which is just equal to $A$. But I dont think this tells me anything...  But that's about all i know, any help will be appreciated

I can't find the missing link between singularity and zero eigenvalues as is stated in the following proposition:  A matrix $A$ is singular if and only if $0$ is an eigenvalue.  Could anyone shed some light?


Given $A$ is a nonsingular $3\times3$ matrix prove that if $AA^T=I$ then it is not necessary that $A^TA=I.$  Ie show shat for a matrix to be orthogonal its necessary that both $AA^T=I$ and $A^TA=I.$  Attempts- i tried to use variables for A but could not do it. As a habit if i take A^-1 =AT then the solution becomes wrong.

If $A$ and $B$ are square matrices such that $AB = I$, where $I$ is the identity matrix, show that $BA = I$.    I do not understand anything more than the following.   Elementary row operations. Linear dependence. Row reduced forms and their relations with the original matrix.   If the entries of the matrix are not from a mathematical structure which supports commutativity, what can we say about this problem?  P.S.: Please avoid using the transpose and/or inverse of a matrix.


How many anagrams of the word mississippi are there that have at least two consecutive i’s? My approach was: Finding the total amount of anagrams (11! / 4! 4! 2!). And then to calculate the amount of options without 2 consecutive i's. In the end, to find the difference between them. However, the result felt me to big intuitively. Do I miss something?  Thanks

In how many ways can the letters of the word $MISSISSIPPI$ be rearranged ?   I am confused on whether it is  $\dfrac{11!}{4!4!2!}$ or $\dfrac{11!}{4!4!2!}-1$  since it is given rearranged and not arranged.


What can I use to prove the following:  If $f:[0, \infty[ \rightarrow \mathbb{R}$ integrable in all $[0,c]$, $c>0$ and  if (limit exists and) $$\lim_{x \rightarrow \infty} f(x) \not = 0$$ then  $$\int_0^{\infty} f(x)dx$$ diverges.  I understand the idea that the integral must diverge, since the terms of the sequence never go to zero (i.e. the integral or the sum continues accumulating to infinity).  However I'm lost as to what kind of notation to use to display this. I think I don't need Riemann sums in this.

Is the following true or false:  If $\int_0^{\infty} f(x)dx$ converges and $\lim_{x\rightarrow \infty} f(x)$ exists, then $\lim_{x\rightarrow \infty} f(x)=0$?    This should be doable without series.


size of int in my system is 4 bytes and char is 1 byte ,so I thought size of this struct will be 10(4+6) bytes.  struct Riddle {     int n;     char s[6]; };   but it is 12 bytes(checked with printf("%d",sizeof(Riddle)).  this might be a stupid question ,but it really confused me.  can you explain to me how is it possible?  thanks for help.

Why does the sizeof operator return a size larger for a structure than the total sizes of the structure's members?


I am a Ph.D. student and currently I am studying Bayesian inference concerning vector autoregressive models. A lot of researchers when talking about uninformative prior, conclude that the results of inference are equal to what we can obtain using OLS. My question is: if this is true, why I should use Bayesian inference instead of OLS?

If the interest is merely estimating the parameters of a model (pointwise and/or interval estimation) and the prior information is not reliable, weak, (I know this is a bit vague but I am trying to establish an scenario where the choice of a prior is difficult) ... Why would someone choose to use the Bayesian approach with 'noninformative' improper priors instead of the classical approach?


This user has more than 200 rep. On Stack overflow but why he hasn't got the +100 association bonus on Super User?    Link to user:

Is it still a thing? I don’t think I’ve ever seen it.   Ask Ubuntu: 264 Meta SE: 81 Linguistics: 56 Area 51: 51 (spooky!) Super User: 33 Unix & Linux: 3 Stack Overflow | User Experience | Bicyles | Video Production | Music: Theory & Practice | Retrocomputing | Genealogy & Family History | Joomla: 1


my object is a 3d scan and is basically a shell with a mesh and image textures. i've heard about retopo but the problem is i don't have a model to retopo on. just a shell. is there another way to convert this to low poly but keep the detail?

I'm making a game in the unity engine and for my models i'm using blender 2.6. The thing is that i'm pretty new to graphics design (modeling, sculpting, etc) and by following some tutorials i've managed to make some very high poly meshes for my characters with the sculpt editor, the meshes have about 1.5M - 2M faces and of course a game character should be less than 30K faces so the game runs smoothly with good optimization on an average pc.  my question is how do i translate the details of the high poly stuff to low poly meshes (7k - 30k faces), i've heard about uv unwrapping and stuff but i'm not sure what is the process to follow.  i don't mind if the recommendation is very hard and for advanced users because the primary thing i want to do with this, is to learn.


Could a second black hole be used to create a gradient that reaches into the event horizon of a first black hole so that what's inside it can escape through the gradient?  Maybe you would have to use a lot of black holes and be able to plot or control their position precisely.

Suppose we have a spacecraft just inside the event horizon of a black hole, struggling to escape, but slowly receding into it. Another (bigger) black hole expands until its event horizon includes the spacecraft as well. This pulls both the black hole and space-craft into itself. As the spacecraft is closer to the second black hole, it receives more force, perhaps just enough to pull it out.  Is it possible that the spacecraft, even momentarily, is pulled out of the event horizon of the original black hole (although it is now trapped inside the event horizon of the new one)?


My guess is that no such $G$ exists. All I know is that if $\mathrm{Aut}(G)$ is abelian, then $G$ is two-step nilpotent. Since $\mathbb{Q}$ is locally cyclic (i.e. every f.g. subgroup is cyclic), can we say more about $G$ in this case? Must it polycyclic-by-finite?  What I can show is that there is no group whose automorphism group is $\mathbb{Z}$.     Proposition. There is no group $G$ such that $\mathrm{Aut}(G)\simeq \mathbb{Z}$.   Proof. If $\mathrm{Aut}(G)\simeq \mathbb{Z}$, then $G/Z(G)$ is cyclic (because it is isomorphic to $\mathrm{Inn}(G)$, and is therefore isomorphic to a subgroup of $\mathbb{Z}$), and this implies that $G$ is actually abelian. Let's write $G$ additively: then the inversion map $\sigma(x):=-x$ is an automorphism $\sigma:G\rightarrow G$ with $\sigma^2=1$. Since $\mathbb{Z}$ has no elements of order $2$, the only possibility is $\sigma=1$, which means $2x=0$ for all $x\in G$. Therefore $G=V$ is actually an $\mathbb{F}_2$-vector space, infinite-dimensional since $G$ has to have infinite cardinality. But then $\mathrm{Aut}(G)=\mathrm{GL}(V)$ is not abelian (e.g. it contains finite symmetric groups). QED    Now I want to show the same result with $\mathbb{Z}$ replaced by $\mathbb{Q}$.  If $G$ is a group with $\mathrm{Aut}(G)\simeq \mathbb{Q}$, then perhaps by mimicking some Galois theory, we can find a group $H$ so that $\mathrm{Aut}(H)\simeq \mathbb{Z}$? This would contradict the above proposition.  (Sorry if this is a duplicate, but I did a lot of searching and found nothing before deciding to post.)    Here is another attempt along the same lines.     Proposition. There is no finitely-generated group $G$ such that $\mathrm{Aut}(G)\simeq \mathbb{Z}$.   Proof. Same technique as above. If $G$ is finitely-generated, then $G/Z(G)\simeq \mathrm{Inn}(G)$ is a finitely-generated subgroup of $\mathbb{Q}$. Since $\mathbb{Q}$ is locally cyclic, it follows that $G/Z(G)$ is cyclic, so $G$ is abelian and we're done. QED

Prove that there is no group $G$ s.t. $\operatorname{Aut}(G)=\mathbb{Q}$  I get the feeling that we should proceed by contradiction.   So let $G$ be a group s.t. $\operatorname{Aut}(G)=\mathbb{Q}$. Then we can identify elements of $\mathbb{Q}$ with automorphisms of $G$... and identities such as $\frac{1}{2}*2(g)=1(g)=g$  Can somebody help me find a contradiction?


Let $X$ be a topological space. Is there any topological property on $X$ that be equivalent to $C(X,\mathbb R)$ be noetherian ring?

Let $X$ be a topological space. Is there any topological property on $X$ that be equivalent to $C(X,\mathbb R)$ being a noetherian ring?


How to Move points according to distance and azimuth ?

I have an excel spreadsheet with header and survey drill data. Header data contains hole ID, and location coordinates, and the survey data contains related downhole survey with Distance, Azimuth and Dip values.   Since I know the hole location and surface elevation, I would like to be able to convert the survey table to XYZ coordinates as well.  Does anyone has a function / procedure / example?  (VB & ArcObjects)  Header Data:    Survey Data:


I'm trying to learn how I can stretch the width of my plot both when showing (plt.show()) it and saving (plt.savefig) it.  More precisely, the plot has two y-axes that I have written as follows:  fig , ax1 = plt.subplots() ax2 = ax1.twinx() ax1.plot(x,y) ax2.plot(x,y2) plt.show()   Now the question is, how can I specify the size of the plot, e.g., how do we stretch the width/height?  When using plt.show() and the plot appears, I can manually take one corner and resize the box however desired, but that manually customised size will not be the saved one.

How do you change the size of figure drawn with Matplotlib?


The solution proposed in the  does not seem to work for me as you can see below..    I have a rather huge list (2500 items) on SharePoint 2013 and I would like to get an idea of how many items that meets selected criterias, but I'm unable to get it working like i would like.  I know the itemcount endpoint, however that only returns the total amount of items in the list and I cannot seem to filter that.  I've tried this which I have found somewhere on this site:  _api/web/lists(guid'D38E6516-FB4F-4FCF-9E29-4FEC9CE06D2B')/Items/$count?&$filter=startswith(Title,'T757388')   But that only returns an error.  If I was dealing with a small list I would just make a normal Query and Count the items in the array, but the payload size exceeds the limit if I try this.  Anybody able to cast some light on this?

I am attempting to return an integer (itemcount) of the items within a SP2013 list. I have done this easily using the stock standard json method. However I have a need of counting the splist items which contain a certain value. My silly knowledge immediately lead me to try and use filtering with the ItemCount parameter only to find out that it will always still return the count for all items and it will completely ignore the filter. I have searched for a way of doing this but have found absolutely nothing other than a single page with a comment stating that it is not possible with the REST api and that it can ONLY be done using CSOM.  My question is, firstly, is it true that there is NO way to filter itemcount with REST? If so, how else can I obtain my item count using this type of filtering? (Examples or sources will help vastly) Thanks.  Below is my attempted request:  var itemid = item.id;           MyService.ensureFormDigest(function (fDigest) {               $http.get(                   MyService.appWebUrl + '/_api/web/Lists/getbytitle(\'Items\')/ItemCount?$filter=SubjectsID eq' + itemid,                   {                       headers: {                           'Accept': 'application/json; odata=verbose',                           'X-RequestDigest': fDigest                       }                   }).success(function (d) {                       item.itemcode = d.d.ItemCount;                       alert(item.itemcode);                       callback();                   }).error(function (er) {                       alert("Error getting List Item Count: " + er);                   });           });       }   On another note, I was advised to try it as such: /Items?$filter=SubjectsID eq 3&$select=Id  Then in the JS, in my success method:  data.d.results.length


I have a loop like  for (int i = 2; i <= ViewBag.numPages; ++i)   and I'm wondering if it'll be faster if I write it as  for (int i = 2, n = ViewBag.numPages; i <= n; ++i)   Please give me a deep (low-level) explanation if possible

I know that in JavaScript, creating a for loop like this: for(int i = 0; i < arr.length; i++) is costly as it computes the array length each time. Is this behavior costly in c# for lists and arrays as well. Or at compile-time is it optimized?  Also what about other languages such as Java, how is this handled?


The Problem: ( 270 + 370 ) is divisible by which number? [ 5, 13, 11 , 7 ]  Using Fermat's little theorem it took more than the double of the indicated time limit. But I would like to solve it quickly as I am preparing for an exam, that would require us to solve each MCQs to be solved in 4 minutes on an average.    Thanks in advance.

Show that $13$ divides $2^{70} + 3^{70}$.   My main problem here is trying to figure out how to separate the two elements in the sum, and then use Fermat's little theorem. So how can I separate the two?  Thanks!


I noticed that  (about basic  syntax) received a lot of downvotes as soon as I posted it. Is there any specific policy against the posting of questions with "obvious" answers on Stack Overflow?  I'm unclear as to why questions with "obvious" answers aren't usually well-received by the community - are beginner questions considered harmful for some reason? ("Obvious" is a relative term, of course - this type of question would be helpful to anyone who was learning C# for the first time, but it wouldn't be helpful to an experienced C# developer.)

I asked a question that apparently offended a number of c++ programmers, and made me realize that there are some things I didn't know about C++.  Here is a link:    Unless I am free to express some ignorance, how am I supposed to ask a question (any question)?  To be clear, I'm not upset about this, and I welcome the comments and answers.  But I do notice that some questions do not get answered, or are treated with disdain by the community, because the question is perceived as an ignorant one.  Is this an "I'm superior to you" attitude?


I've been looking into tools like Karabiner, which are cool, but I would like more control. In general, I'd like to remap specific keys to run AppleScript or some other code.  Ideally it wouldn't send the keystroke though to the active application.  Is there any way to do this?  At the moment I'd like to remap the numpad keys to focusing specific applications, and if possible, specific windows in those applications. A general way to run code would be best, but anything that can accomplish this would be very much appreciated.

I need to run an AppleScript using a keyboard shortcut. How can I do that?   I think about    Save AppleScript in textual format. Use Keyboard Maestro to launch 'osascript' to run the script when the matching keyboard shortcut is called.   What do you think? Is there better way to go?


I have .tex document into which "thinspace" was inserted, most likely while copying text from another document. I am currently using \DeclareUnicodeCharacter{2009}{\,} to skip over this occurrence. Is it possible to search and delete this character from the document itself as it is not required. I am using a Linux Mint 20.1, pdflatex and Texmaker as the frontend.

When I try to cite more than two authors, I got this: ! Package inputenc Error: Unicode char  (U+200B) (inputenc)                not set up for use with LaTeX.   \documentclass[a4paper,oneside,BCOR=10mm,12pt,titlepage]{scrreprt}  \usepackage[polutonikogreek,ngerman,english]{babel} \usepackage[maxlevel=4,autostyle,german=guillemets]{csquotes} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[style=mla]{biblatex} \DeclareMultiCiteCommand{\parencites}[\mkbibparens]{\parencite}{\multicitedelim}  \begin{document}  \parencites[cf.][]{key1}{key2}{key3}  \end{document}


Postgres version: 11  I've got 2 roles - one used for read and one for write on the same database.  CREATE ROLE reader WITH login; CREATE ROLE writer WITH login;  CREATE DATABASE thedatabase;  GRANT SELECT ON all tables in schema public TO reader; GRANT INSERT ON all tables in schema public TO writer;   Everything is fine for all the existing objects in the database, but as soon as another object is created both users will need a GRANT SELECT/INSERT to be able to perform their duties.  Is there a config to overcome this?

SO and Internet contains a lot of answers to question how to create read only user (for example see  article), BUT all of them promote the following way:   Create user Grant USAGE privilege to all existing schemas Grant SELECT privilege to all existing tables in all existing schemas Grant default SELECT privilegie to all tables (which can be created in the future) for all existing schemas   But what to do if some schemas can be created in the future too?   I mean I want to grant read only permissions to these schemas (and tables in these schemans) created in the future without any additional configuration. Is it possible?


Is there somehow I can check if a file or folder exists in Ubuntu Terminal?

So I have a filename bobv1.txt, and I don't want to manually check to see if bobv2.txt is on the site. On the site bobv1.txt will be replaced by bobv2.txt. I have downloaded the the html page and determined the full download path of bobvX.txt and I know were the file is in my file system. How can I tell if the file is already on my file system? I need this to work for all subsequent versions.


I have function that should be triggered on click and there is two different elements that can do that. One element is static created on page load, and the second element is dynamic. I'm wondering if there is a way to combine this in single statement with JQuery. Here is example:    $('.show_new').on('click',showElement); function showElement() {   $('#test').append("<input type='button' id='dynamic' class='save_form' value='Save'>") }  $('.save_form').on('click',testFun); $(document).on('click','.save_form',testFun); function testFun(e) {   alert(e.target.id); }   <input type="button" class="show_new" value="Show"> <input type="button" class="save_form" id="static" value="Save">

     As you can see in example above the only way for this to work is to have to lines one for static and one for dynamic element event. If anyone knows better way of doing this please let me know. Thanks!

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


Hello everyone i need your help.  I have installed  ubuntu but it is experiencing  a lot of  overheat issues and it  can't  stay on for more than 5 mins.  So i decided  to  install windows but it is showing an error that it cannot be installed  on  disk 0 parition 1.   So i was asking is there any good os which does not  have  any overheat issues and is easily installable

I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.


In this, "to be" is the base verb, conjugated in the first, singular, present tense "am". The verb is then put in a contraction with first, singular, pronoun "I" to create "I'm". This contraction is then made into a phrasal verb by adding either of the adjectives "up" or "down".  I am curious about why, in these cases, adding the prepositional phrase "for that" changes the meaning between the examples (2) and (4) which use "up".   But the change in meaning does not occur between (1) and (3).     (1) I'm down for that   (2) I'm up for that     (1) and (2) both parse as someone stating their own interest/availability for what "that" refers to. As in, for example, Person A asking "Want to go to the movies?" and Person B replying either "(1) I'm down for that" or "(2) I'm up for that".     (3) I'm down   (3) parses as someone stating their own interest/availability. In the same example, Person A asks "Want to go to the movies?" and Person B replies "(3) I'm down". So, saying "(1) I'm down for that" and "(3) I'm down" both have pretty much equivalent meaning in colloquial English.        (4) I'm up   (4) parses as someone stating they "are up" as in... a) they have physically stood up or, b) they are now conscious (after being asleep or unconscious).    So in the conversation example, Person A asks "Want to go to the movies?" and if Person B replies "(4) I'm up" -- it would be a strange answer.   Comparing "(2) I'm up for that" and "(4) I'm up" -- these do not have equivalent meaning. Adding the prepositional phrase "for that" changes the focus and meaning of the sentence. In (2) the focus is that the "I" is interested/available. In (4) the focus is on the state of being, not their interests.  Is there any slang etymology about "up" and the verb "to be" being combined as a phrasal verb? Additionally, is the effect of the prepositional phrase "for that" something that has trends, or is is an interesting isolated case in the situation of (2) vs (4)?

I understand it's an expression of agreement. What exactly does it mean and where did it originate from?


This is how you used to be able to do it in blender 2.79   I can't find this option in 2.8

In my scene it is required to position the lights close to the main object like this:    How I can make the light source invisible to the camera?


With the TeX code  \begin{equation}   \max\left\{ \sum_{i=1}^{n}|\langle x^{(i)},b\rangle|^2\;\mid\vbox{   \hbox{Condition 1}   \hbox{Condition 2}   \hbox{Condition 3} }\right\} \end{equation}   I get the output    How can I achieve the following two things?   The separator produced by \mid shall have the same height as the curly brackets. The three conditions shall be centered vertically.

I was wondering what the proper LaTeX code would be to display something like this:    You don't have to include the mathematical symbols, what is important is the structure.


I have a question about SAS and R. For a research, I used a longitudinal data and I initially used SAS (GLIMMIX) and then I analyzed the data with R (glmer) programming. There are differences between p-values of SAS and R. I expected that regression coefficient and standard error could be different for R and SAS. But there are differences for p value for some variables, which are significant in R, are not significant in SAS.   My R model and SAS model are respectively :  #R m3.glmm <- glmer(y ~ timebefore + timeafter + x1 + x2 +...+ x11 +                            (1+timebefore+timeafter|id),                   data=data, family=binomial(link="logit"), nAGQ=3)  #SAS proc glimmix data=data METHOD=QUAD(QPOINTS=3) NOCLPRINT ;   class id x2 x3 x4 x5;   model y(event='1')=timebefore timeafter x1 x2 x3 x4 x5          x6 x7  x8 x9 x10 x11 /solution CL link = logit dist = binary;   random intercept timebefore timeafter/subject = id GCORR SOLUTION; run;   Eg: variable "x1"(defined as age) was significant (p val= 0.04) in SAS but not in R (p val=0.1). But others were similar. It means that significant variables in SAS are found significant in R, or insignificant variables in SAS are insignificant in R.   Does anybody know about the differences?

I am a user more familiar with R, and have been trying to estimate random slopes (selection coefficients) for about 35 individuals over 5 years for four habitat variables. The response variable is whether a location was "used" (1) or "available" (0) habitat ("use" below).  I am using a Windows 64-bit computer.  In R version 3.1.0, I use the data and expression below. PS, TH, RS, and HW are fixed effects (standardized, measured distance to habitat types). lme4 V 1.1-7.   str(dat) 'data.frame':   359756 obs. of  7 variables:  $ use     : num  1 1 1 1 1 1 1 1 1 1 ...  $ Year    : Factor w/ 5 levels "1","2","3","4",..: 4 4 4 4 4 4 4 4 3 4 ...  $ ID      : num  306 306 306 306 306 306 306 306 162 306 ...  $ PS: num  -0.32 -0.317 -0.317 -0.318 -0.317 ...  $ TH: num  -0.211 -0.211 -0.211 -0.213 -0.22 ...  $ RS: num  -0.337 -0.337 -0.337 -0.337 -0.337 ...  $ HW: num  -0.0258 -0.19 -0.19 -0.19 -0.4561 ...  glmer(use ~  PS + TH + RS + HW +      (1 + PS + TH + RS + HW |ID/Year),      family = binomial, data = dat, control=glmerControl(optimizer="bobyqa"))   glmer gives me parameter estimates for the fixed effects that make sense to me, and the random slopes (which I interpret as selection coefficients to each habitat type) also make sense when I investigate the data qualitatively. The log-likelihood for the model is -3050.8.  However, most research in animal ecology do not use R because with animal location data, spatial autocorrelation can make the standard errors prone to type I error. While R uses model-based standard errors, empirical (also Huber-white or sandwich) standard errors are preferred.   While R does not currently offer this option (to my knowledge - PLEASE, correct me if I am wrong), SAS does - although I do not have access to SAS, a colleague agreed to let me borrow his computer to determine if the standard errors change significantly when the empirical method is used.  First, we wished to ensure that when using model-based standard errors, SAS would produce similar estimates to R - to be certain that the model is specified the same way in both programs. I don't care if they are exactly the same - just similar. I tried (SAS V 9.2):  proc glimmix data=dat method=laplace;    class year id;    model use =  PS TH RS HW / dist=bin solution ddfm=betwithin;    random intercept PS TH RS HW / subject = year(id) solution type=UN; run;title;   I also tried various other forms, such as adding lines  random intercept / subject = year(id) solution type=UN; random intercept PS TH RS HW / subject = id solution type=UN;   I tried without specifying the   solution type = UN,   or commenting out  ddfm=betwithin;   No matter how we specify the model (and we have tried many ways), I cannot get the random slopes in SAS to remotely resemble those output from R - even though the fixed effects are similar enough. And when I mean different, I mean that not even the signs are the same. The -2 Log Likelihood in SAS was 71344.94.   I can't upload my full dataset; so I made a toy dataset with only the records from three individuals. SAS gives me output in a few minutes; in R it takes over an hour. Weird. With this toy dataset I'm now getting different estimates for the fixed effects.   My question: Can anyone shed light on why the random slopes estimates might be so different between R and SAS? Is there anything I can do in R, or SAS, to modify my code so that the calls produce similar results? I'd rather change the code in SAS, since I "believe" my R estimates more.   I'm really concerned with these differences and want to get to the bottom of this problem!  My output from a toy dataset that uses only three of the 35 individuals in the full dataset for R and SAS are included as jpegs.         EDIT AND UPDATE:  As @JakeWestfall helped discover, the slopes in SAS do not include the fixed effects. When I add the fixed effects, here is the result - comparing R slopes to SAS slopes for one fixed effect, "PS", between programs: (Selection coefficient = random slope). Note the increased variation in SAS.


I have a Wordpress site that successfully has 6 sub-pages listed below the main result in Google. However a page content snippet is showing up or each instead of the sub-page meta descriptions.  I have verified in the page source that the meta descriptions are being successfully inserted by my SEO plugin.  How can I define the sub-page descriptions?

My website used to have sitelinks and now it doesn't. It's very possible that it's due to changing the website to a sidebar design instead of having an "interstitial" type landing page which limited the number of choices, but I'm not sure.  Here is how sitelinks might look for a site:    What are some things that I can do to improve my chances of getting sitelinks?


says deleting your own question exceeding some limit results in a penalty.  Is there a penalty for deleting one's own answers? Apparently 5 answers can be deleted per day.   Are there any users that are banned because of deleting answers constantly?  What is the moderators' thoughts about this issue?  For example, if a user gives about ten answers and deletes five of them regularly, will he/she be suspended?

I have read lot of questions related to deleted questions or answers to be available for users to see in their profiles, but my question is, does excess deletion of our own questions and answers attract penalty from the owners/moderators of SO?  Sometimes what happens is, when we see a question, we don't understand it properly but jump into them to answer to get early upvotes and later (when we get downvoted) we realize our mistake and would want to delete our own answers. The reason could be any of the following:   The answer is just not reasonable enough for the question asked. To save your reputation points and avoid further downvotes. Your answer has 0 upvotes and a better answer is already available for the question. The question gets edited and your answer is no longer valid. New people would not know that the question has been edited and they start downvoting your answer since it's no longer relevant.   In doing this we might go to extreme cases, maybe in the range of deleting hundreds of our answers. So is there an upper limit for the number of answers we can delete in order to avoid penalty (if there is any such penalty for deletion)?


I found that in a simple regression model y=β0+β1x+ε, the parameters β0 and β1 are negatively correlated. Is there a explanation for this correlation? I found this property , but I would like to know how is that both parameters are correlated. Thanks

In a simple regression model,   $$ y = \beta_0 + \beta_1 x + \varepsilon, $$  the OLS estimators $\hat{\beta}_0^{OLS}$ and $\hat{\beta}_1^{OLS}$ are correlated.   The formula for the correlation between the two estimators is (if I have derived it correctly):  $$ \operatorname{Corr}(\hat{\beta}_0^{OLS},\hat{\beta}_1^{OLS}) = \frac{-\sum_{i=1}^{n}x_i}{\sqrt{n} \sqrt{\sum_{i=1}^{n}x_i^2} }. $$  Questions:   What is the intuitive explanation for the presence of correlation?   Does the presence of correlation have any important implications?   The post was edited and the assertion that the correlation vanishes with sample size has been removed. (Thanks to @whuber and @ChristophHanck.)


im a JS beginner and I'm a bit confused of this code: let array = ["string1", "string2"] let arrayCopy = array array[0] = "changedString" console.log(arrayCopy) // Returns Array ["changedString", "string2"]  Why is the assignment of Array also mutating the copy?

The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).  Although it doesn't really matter at the end, I want to know what is the correct way to present the arguments passing conventions. Is there an excerpt from JavaScript specification, which defines what should be the semantics regarding this?


What can you call a 3rd person who's gender is unknown?  He - Male She - Female  I've never heard of an unisex word for 3rd person.

Is there a pronoun I can use as a gender-neutral pronoun when referring back to a singular noun phrase?  Each student should save his questions until the end. Each student should save her questions until the end.


How would evaluate the the following limit:  $$\lim_{n\to\infty} \frac {1}{n^{\frac{2}{n}}}$$  Would $n^{\frac{2}{n}} = n^0$ If this can not be evaluated like this, could I use l'hopitals rule, and if so how?

I've spent the better part of this day trying to show from first principles that this sequence tends to 1. Could anyone give me an idea of how I can approach this problem?  $$ \lim_{n \to +\infty} n^{\frac{1}{n}} $$


If my Monk uses an action to cast Blade Ward, can I use my bonus action to make an unarmed strike?

I'm playing a 5e Wizard/ Monk build. My DM and I are questioning the viability of the cantrip Shocking Grasp. As a monk I can do another unarmed strike as a bonus action after I attack with a melee attack. Being a touch spell, can I punch (touch) with Shocking Grasp and then do my monk's bonus action?


How to show that, for any given left tail probability, the corresponding quantile of standardized t distribution is increasing in degree of freedom for left tail probability less than 0.5? This is obvious when we check statistical tables. But how can we show it analytically?  Can anyone share any thoughts?

This question is related to a couple of other questions ( and ) relating to some material that I teach in sampling theory.  Consider the critical points of the  defined as follows.  The value $t_{n-1, \alpha/2}$ is a function of $n$ defined by the implicit equation: $$\frac{\alpha}{2} = \frac{1}{\sqrt{(n-1) \pi}} \cdot \frac{\Gamma(\tfrac{n}{2})}{\Gamma(\tfrac{n-1}{2})} \int \limits_{t_{n-1, \alpha/2}}^\infty \Big( 1+ \frac{r^2}{n-1} \Big)^{-n/2} dr.$$ Normally we treat the input $n>1$ as an integer, but it is possible to extend the treatment to consider it a real value (since the T-distribution is well-defined for non-integer degrees-of-freedom).  I'm trying to come up with a (relatively simple) proof that this critical point value is decreasing in $n$, but I seem to be making quite a mess.  Differentiation using Leibniz rule gets part way, but it quickly becomes a bit of a mess.  Consequently, I would like to solicit proofs of this result --- this simpler the better. Question: How do you prove that this critical point is strictly decreasing in $n$?


Prove that if $0\le p_n \lt 1$ and $S:=\sum p_n \lt 1$, then $\Pi (1-p_n) \ge 1-S$.  I'm having real trouble proving this inequality. I'd greatly appreciate any help.

Let $A_n$ be independent events with $P(A_n) \neq 1$. Show that $\prod_{n=1}^{\infty} (1- P(A_n))=0$ iff $\sum P(A_n) = \infty$  It kind of looks obvious but I really have no idea how to prove it. Can someone give me help?


I know that an ordinal is regular if its equal to is cofinality, but how is that related to cardinal?

In the proof of the lemma     For every limit ordinal $\alpha$, $\textrm{cf } \alpha$ is a regular cardinal    Jech says that     It is easy to see that if $\alpha$ is not a cardinal, then using a mapping of $|\alpha|$ onto $\alpha$ one can construct a cofinal sequence in $\alpha$ of length $\leq |\alpha|$, and therefore $\textrm{cf } \alpha < \alpha$.    I've spent a while trying to construct this cofinal sequence and was wondering if I was on the right path:   From a bijection $f$ between $\kappa = |\alpha|$ and $\alpha$ take $S = \{\beta \in \kappa : \ f(\gamma) < f(\beta)$ for all $\gamma < \beta\}$ then if $\xi$ is the order type of $S$ and $g$ is the isomorphism from $\xi$ to $S$ the function $f\circ g$ is a cofinal sequence in $\alpha$ and $\xi < \alpha$.   Is this on the right track, or is there an easier way of doing it?


Can you transfer items that you already bought on a PS4 account to another PS4 account? The accounts are in the same console, and I need to know how.

So the problem is that account 1 and account 2 bought a game together, but account 1 isn't used anymore. Can we transfer the game license from account 1 to account 3?   The game was bought on account 1 and account 2 activated account 1 as primary.


Can I install Ubuntu Touch on Moto G2 XT-1068?

With the announcement of the Ubuntu Phone OS I'd like to know what phone (and tablet) models are supported at this time.  Note from foss & Oli: We are making this the master question for all future "Will this work on <insert random tablet/phone/device here>?!" questions


Let B be a tensor-valued variable, taking values from the set of second order tensors on the vector space naturally associated with Euclidean 3-space.   It is given that B is invertible.  I am looking for a proof of the following statement:  $$ \frac{\partial (\log \det \mathbf{B})}{\partial \mathbf{B}} =  \mathbf{B^{-T}} $$  Also, it seems one would need an assumption on the positivity of the determinant of B, so I am guessing this is allowed too.  Thanks.

Let $A$ be a positive definite matrix. Compute the derivative of $\log \det A$ with respect to $A$.  Here's what I have thus far.  \begin{align*} \frac{d}{dA}\log (\det (A)) &= \frac{1}{det(A)}  \frac{d}{dA}(det(A))~ \text{, By chain rule}\\ \end{align*}  I know that $\frac{1}{det(A)}  \frac{d}{dA_{i,j}}(det(A)) = \frac{1}{det(A)} (adj(A)_{i,j})^T$. Additionally that $A^{-1} = \frac{1}{det(A)} adj(A)$.  I'm under the impression that the solution is  $\frac{d}{dA}\log (\det (A)) = 2A^{-1} - (A^{-1} \circ I)$. Where $\circ$ is Hadamard product.   I'm missing some understanding about the adjoint matrix to connect it to the solution.


I am trying to print no of  node values in a given range in an avl tree .But when I try to run the program I get NullPointerException.  I couldn't get much help from previous questions of same topic.How can i correct it here.Here's my code of that portion:  public void range(int low, int up){     if(low >up){         System.out.println("Illegal input");     }      if(this.root != null){         System.out.println(rangeS(this.root,low,up) +"");     }  }  public static int rangeS(AvlNode root,int k1 ,int k2){     int c = 0;     if(root.key >= k1 && root.key <= k2){         c = c+1;     }     if(root.key > k1 ){         rangeS(root.left,k1,k2);     }      if(root.key <k2){         rangeS(root.right,k1,k2);     }     return c; }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


What is going on here??  Bunch of *.html and *.htm files in my directory, I do a del *.htm and after that the *.html files are also gone:    I noticed it happening in Total Commander when I typed the command, then checked that it also happens in a (CMD) command window.  The extension is not essential, the same happens with e.g. fantasy extensions *.bon and *.bonk  Win XP SP3

I'm trying to recursively search a directory tree to find all of the .asp files using the following command:  dir *.asp /s   For some reason, this returns not only the asp files, but also the aspx files.  How can I force it to ignore the aspx files?


I need to do the small animations in Ubuntu 12.04 Please let me know what type of animation software are available for Ubuntu 12.04?  If I can install the Adobe Flash Professional to my Ubuntu 12.04 is better.

Is there commercial-grade computer animation software available for Ubuntu, similar to the professional software sold for the Windows operating system?  This question goes out to those of you who may be using such software professionally.  My daughter recently graduated from the Art Institute of Seattle, and needs to put together an animation portfolio in order to interest employers in the field.  As you know, such software is usually provided by the employer and the costs are high - several thousand dollars.  I suggested that she investigate Ubuntu as a possible way to acquire the tools she needs.  But, since I have no idea what might be available, either as open source or proprietary animation software, I am reaching out to the Ubuntu community for help in the hope someone who is using such software can help her.  Thank you for reading this post, and for any information you might have.


Given an X sided die, and Y throws, what is the probability that the sum of the throws is greater than or equal to Z? For example, given a 6 sided die and 5 throws, what's the probability that the sum is at least 10? I tried to do this by trying to figure out the probability of of each individual possible value, but I couldn't get it to work out. What is the approach to this? Is there an easy programmatic way of figuring this out?

This is a dice problem  1) I want to calculate the probability to have more than X throwing 3 dice of 6 faces. X = addition of the result of the 3 dice.  2) This is the first step but if you can also provide me a solution to calculate the probability to have more than X with Y dices of Z faces it would be really great.


A small ship or escape pod has landed on a planet with one living survivor. I think it is the regular waste dumps that - over the period of a year or so - alter the local ecology outside, somehow making the environment more suitable so that the character could have lived longer, had they known. I think there is some kind of threshold effect - once the change in the local chemistry started, it continued on its own. Written in the 80's or 90's?

All die but one, he continues to try to grow plants.... he dies at the end, but is successful growing stuff. I seem to recall the problem might be ammonia in the soil or the air..?


Every time I try to install Xcode from within the Mac App Store, I get "Download for free? This item will be added to your Purchases and will be available even if your Family Sharing Status changes".  I click Download. Then I see a spinning wheel for a second until I get the same message again until I just press 'Cancel'. It never downloads.    Does anyone know what the deal is?  I'm on a fresh install of OS X 10.9. Only thing I've done to it is sign in to the Mac App Store using my New Zealand account. I also installed and updated Office 2011. So I certainly haven't done anything unusual to this Mac!

My App Store keeps saying this item is free in the store, that this item will be added to your purchases and it then says cancel or download.   I click download and it won't download and keeps popping up the same message over and over again.  How do I make it stop? I can't download any apps.


How to make this icon in Illustrator/Photoshop or any other software for that matter?

I want to create a radar like the one bellow, where the gradient goes darker and darker clockwise. in the left it is totally transparent, while in the right it goes to 60%.  I tried to add linear gradients, to overlap more of them to create a similar effect, but it just doesn't look good enough. How would you do it?


I have made a grid curve which I beveled for a final result which looks like this:    I am making an animation out of this, which will make the grid object wave like a flag. To do so, I have shrinkwrapped the grid object to a moving wavy plane, so that the result looks like this:    Now, the problem is that not only did the curve get shrinkwrapped onto the plane, but also the bevel. Which makes the whole thing flat, as can be seen in the GIF. How can I fix this?  One solution I can think of would be to "bake" the waving animation onto the curve so that I don't need the shrinkwrap addon anymore, thus letting me bevel the curve independently. Unfortunately, I do not know how I can do this.  Thanks for reading!

The title is probably very confusing, but here's the situation:  I'm animating a flat grid curve by shrink-wrapping it onto a moving plane in order to get a uniform wave animation, it looks like this:    Before I render it, i want a bevel. What I did then was simply adding a bevel to the curve, making the curve look like this:    Now, when activating the shrinkwrap modifier, I expexted that only the curve would be shrinkwrapped, but alas, the bevel did the same:    As seen by the blue spots, the curve has been completely flattened along with the bevel.  How can I avoid this? I tried using a wave modifier instead of shrinkwrap, but this modifier doesn't seem to make perfectly round waves like this:    So, any thoughs on how to solve this?  Thanks for reading!


I had Ubuntu 20.04 on an nvme SSD on my laptop and installed Windows 10 after resizing the disk. This is what fdisk shows in the terminal sudo fdisk -l   /dev/nvme01n1p1 EFI /dev/nvme01n1p2 Linux /dev/nvme01n1p3 Windows /dev/nvme01n1p4 Windows  Then I tried reinstalling grub by booting into Ubuntu Live Usb and doing the following sudo mount /dev/nvme01n1p1 /mnt sudo grub-install --efi-directory=/mnt  This give me the error : failed to get canonical path of /cow Thinking maybe I need to use the boot directory, I also tried sudo mount /dev/nvme01n1p2 /mnt #this is where  Linux is intalled sudo grub-install --boot-directory=/mnt/boot /dev/nvme01n1p  This gives me the error: cannot find a GRUB drive for /dev/nvme0n1p. Check your device map My /mnt/boot does have a grub directory. What am I doing wrong? Thanks for any pointers!

I want to reinstall GRUB 2 and I found these instructions: . In my case, the boot loader is installed in the EFI partition. If I use the commands provided in this guide, will GRUB be reinstalled to the EFI partition automatically, or will it be installed into the root partition where Ubuntu is installed ? Obviously, I do not want this to happen.


Should bounty be returned if there is NO answer at all? Or your contribution (to the bounty) only?  This is similar to many questions like  (which was a duplicate itself), but I am referring to only when there is no answer at all. Not no upvotes - no answer.

I have  with a bounty that will expire in a few days. It looks like nobody will get the bounty; only one answer was posted during the bounty period, and it has no upvotes.  In cases like this, the bounty is thrown away.  Why isn't it refunded instead, if no answerer has earned it?


1) Why to use a LDO regulator when a simple voltage divider can do the job for stepping down voltage?  2) How do we set the current in voltage divider when use as regulator functionality ? Or   3) Can we calculate (theoretically) the current sourcing capability of voltage divider output ?  voltage divider output V(out) = Rb/(Ra+Rb) * V(in)  What is the current sourcing capability at V(out) node ?  Regards, Azlum

When would you use a voltage regulator vs a resistor voltage divider?  Are there any uses for which a resistor divider is particularly bad?


Surfing the internet I've casually discovered this band. Any suggestions of similar artists (with this kind of vocals etc)? Thank you !

I'm having a hard time collecting music I'm interested in through genre. Do I have any options to look for similar music based on a recording / song name?  For example, when browsing a video tagged Music on Youtube, Youtube presents a "Youtube mix":    But there does not seem to be any known service for this.


In Blender, after resizing a box - ie you could make it very flat like a square tile, the pivot point of the object will likely be outside. How do I move the mesh and/or the pivot so that the pivot will be located exactly in the center of the mesh?

So, I'm working creating a lamp... yes, newbie here.  After modeling for a bit, I noticed that my point of origin was no longer the center of my object:    How to I reset an object origin point to the center of it's geometry?


Let's say I have a site called test.website.com that I'd like to forward to www.website.com/test.   How can I achieve this via Windows Server 2008 DNS?  I've configured this for external users via GoDaddy Subdomain Forwarding but I can't seem to figure out how to do this internally via Windows DNS.  I tried setting up a CName to do this and although it will redirect pings to the desired URL, it doesn't seem to work for the website itself.  This seems like something basic but I can't seem to figure it out. Thanks for any help in advance.

This is a  about DNS/Hostnames resolution to IPs/Ports   Example 1  I'm running a web server on port 80 and another on port 87. I would like to use DNS so that www.example.com goes to port 87. How can I accomplish this using DNS only?  Example 2  I'm running a service on my server on a non-standard port. How can I get clients to connect to this non-standard port automatically? Can I use DNS? Is there some application specific support where DNS could indicate the IP and Port?   Example 3  Do some application protocols specifically support hostname awareness, and allow special actions to be taken based on this information? Are there other questions on Server Fault that cover some of these?  Commandeering: This question was originally asking about running IIS and Apache on the same server, but the same concepts can be applied to any server software receiving connections from clients. The Answers below describe the technical problems and solutions of using DNS and application protocol support to assign a port number for a client to connect.


I am testing a ranking system for posts, and I'd like help with the below:  Upon publishing a new post, I'd like the post view count to immediately have a random number between 829 and 1013 added to it.  Could you please tell me how I can do that? If you offer any code, kindly let me know exactly where to put it.  Thank you.

Upon publishing an unpublished draft, I'd like the custom meta value "post views count" to be set to a random variable between 829 and 1013.  I am using the code below, which doesn't always work. It works when I create a test draft and publish it immediately, but not when I save a post for a few days or assign it to another writer it doesn't work.     NOTE: I don't want to create a new custom field. I just want to update the existing field, which is called post_views_count.   function wpse_custom_field_on_publish( $new, $old, $post ) {   if ( $new == 'publish' && $old != 'publish' && !get_post_meta( $post->ID, 'post_views_count', true ) ) {     update_post_meta( $post->ID, 'post_views_count', rand(829, 1013), true );   } } add_action( 'transition_post_status', 'wpse_custom_field_on_publish', 10, 3 );


I have one website with currency converter on it and Google WMT is considering the currency words as Content keywords. Is there anyway to block search engine from indexing this Currency Words like "Dollar, pound and all that". I am new in this and any help will be appreciated.

I've been working on a site for a new company that is in the tactical gear/survival gear niche and have ran into a hitch with the keywords that Google ranks for the site.  Namely 4 of the top 5 keywords aren't content related at all, and are elements/functions of the site. The top 5 are as follows:   Tactical Cart Compare Wishlist Quick (from a quick-view function on the site)   My question is how the heck can I avoid this issue? Or CAN I avoid this issue?


I need to restore my documents and folders, since the installation of 14.04 reformatted my harddisk.  I can sign in to Ubuntuone, but I see no way to make it restore the files to my harddisk.

I just installed Ubuntu 14.04, and Ubuntu One isn't installed by default and their download page says it comes pre installed, which doesn't help with anything.  I wanna move all my files from Ubuntu One to Dropbox, but downloading one file at a time from the browser and upload it again to dropbox will take way too long.  Is there any way to get Ubuntu One on Ubuntu 14.04? or somehow download all files from the Ubuntu One website?  I see they updated their site:


I am generating all binary strings of a given length and am trying to store them in a list which I am having trouble with. Here is the code: def generateAllBinaryStrings(n, arr, l, i):        if i == n:          l.append(arr)          print(arr)         return      arr[i] = 0     generateAllBinaryStrings(n, arr, l, i + 1)        arr[i] = 1     generateAllBinaryStrings(n, arr, l, i + 1)        return l  n = 3 l = []   arr = [None] * n  generateAllBinaryStrings(n, arr, l, 0)    i.e. first creating all possible strings with the starting bit as 0 and then all strings with the starting bit as 1. arr stores strings and am trying to append them into a list l. The following print result is right for print(arr) statement but l is not correct. May I know where I went wrong?: [0, 0, 0] [0, 0, 1] [0, 1, 0] [0, 1, 1] [1, 0, 0] [1, 0, 1] [1, 1, 0] [1, 1, 1]  [[1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1]]

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


Please help me complete my answer and find the matrix associated to a given quadratic form, here is my work and effort on that    Here's my attempt to answer it

We have a form: $Q: R^3\to R$, $Q(x) = 3x_1^2 + 3x_2^2 - 2x_1x_2 + 4x_1x_3 + 4 x_2x_3$, where $x = (x_1, x_2, x_3)$ is an arbitrary vector from $R^3$.  The problem is to compute canonical form using Jacobi's Method.  The only problem I've faced is in figuring out how to compute matrix associated to quadratic form $Q$.  Thank you for any advice.  I also know that the base for this form is: $B = \{e_1= (1, 0, 0), e_2 = (0, 1, 0), e_3 = (0, 0, 1) \}$. And that this matrix has the form: $\begin{bmatrix}a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33}\end{bmatrix}$.  Where $a_{ij} = Q(e_i, e_j)$.


When I press F3 in minecraft, it shows everything like normal BUT my coordinates.   I haven't messed with any settings, or done anything really at all. The other day it just stopped showing them.  Is anyone else having this problem, and how do I fix it?

When I press F3 to see the debug screen in I use Minecraft 1.8.1, some information is missing.   Most notably, there are no X, Y, Z coordinates.     What happened to my debug overlay?


I need your help to obtain the grey bars in this matrix:

I have a matrix shown below. I would like to have the whole row green rather than only the cells.   How can I do that?  \begin{equation}\label{eq:appendrow} \newcommand\x{\times} \newcommand\y{\colorbox{mygreen}{$1$}}   \left(\begin{array}{cccc}     \x  & \x  & \x & \x \\     0   & \x  & \x & \x \\     0   & 0   & \x & \x \\     0   & 0   & 0  & \x \\     \y  & \y  & \y & \y \\   \end{array}\right) \end{equation}   The output is:


I'm a software developer, and I sometimes take my work home. However, every time I do that I need to change the ip addresses my software connects to from let 172.28.38.270 to 127.0.0.1. I have tried to change it in the host file by doing this 127.0.0.1    172.28.38.270 but for some reason that don't work, it still tried to connect to 172... and not to 127... when I used to 172... ip.  Does anyone know how to fix this issue? or do I just have to keep changing ip?

I want to map the IP address 192.168.1.222 to 127.0.0.1 so that if I use 192.168.1.222 in the web browser or ping command I get the response (and that from my 127.0.0.1).   Is this possible via routing tables or do I have to add some sort of virtual network adapter?   I try to deal with this problem on a Windows 7 machine and have no other options than a Windows XP maybe.  I'm stuck right there.


So I have this shark model which I animated and ready to export it on fbx and transport it to Unity.  But When I put it on Unity, It looks transparent like this.    Many of the solutions online say that the problem is because of my faces, and they told me to recalculate it or something, but normals are just fine. Is there any other solution?  here's the blend file:

I found someone with , but their answer doesn't work for me. Other than that, the net is full of advice how to flip normals programmatically to create interiors on the fly, but other than "Your normals are wrong", no help.  All my normals point outwards. I exported the object to .obj, imported it into Unity, and got:  Did I apply the texture to the reverse side of the faces, or something like that? How do I fix it?


After spending some time reading  I was convinced to buy the  and I loved it!    The book spanned the time from the beginning to when Agatha escaped the Airship City.  She has not yet been in the wilderness, met the carnival or anything else.  What range of webcomic story does the next book, "" cover?  I'm hoping it starts from the end of the first book and goes on until she is close to castle Heterodyne.  I would like a confirmation whether or not this is the case.

After spending some time reading  I was convinced to buy the book.  I've ordered what I think is the  in my local bookstore (yay local) and it seems to relate to the first one or two years of of web content, but I can't be sure.  My question is: "how does the book series line up with the Web comic?"  Does it contain specific episodes/adventures, relate to strips from a specific time-span or is it simply an assortment of episodes?  UPDATE: They are amazing.  It is interplanetary war in the introduction!!!!  Yes!


Does any one have any suggestions on how I can center content within 'div.footer-widgets .widget.widget_text' the child div is 'div.widget-wrap'. Here is an image link showing you the area within my browser on a local host:   div.footer-widgets .widget.widget_text { height: 250px; }  .widget.widget_text input#subbutton { width:200px; }   Please let me know if I should provide any further information, thank you.

How can I horizontally center a
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Foo foo


I am working on a paper for Elsevier, but the cross reference is not referring to bibliography , as it appear disabled . My code is here   \documentclass[preprint,3p,twocolumn]{elsarticle}   \usepackage{lineno}          \usepackage{pifont} \usepackage{natbib} \usepackage{graphicx} %\usepackage{cite} \usepackage[nodots,nocompress]{numcompress} \usepackage{setspace}   \journal{Computer Networks}   \begin{document}  \begin{frontmatter}    \title{Wireless Sensor Networks Routing: Key Challenges and Open Issues}   \author[a]{Palvinder Singh Mann\corref{cor1}} \ead{psmaan@hotmail.com} \author[b]{Satvir Singh} \ead{satvir15@gmail.com} \cortext[cor1]{Corresponding author.Tel.:+91-9888395367 fax:+91-0181-2205852}  \address[a]{Department of Information Technology, DAV Institute of Engineering and Technology, Jalandhar,Punjab,India.144008.} \address[b]{Department of Electronics and Communication Engineering, Saheed Bhagat Singh State Technical Campus, Ferozepur, Punjab, India.152004.}  \begin{abstract} Wireless sensor networks (WSNs) enable new applications and require non-conventional paradigms for protocol design. Owing to the requirements for self-organization, scalability and primarily low energy consumption needs, a proper balance between communication and data processing capabilities must be maintained. This motivates a huge effort in research activities and investments on this field for past few years. At present most of the research on WSNs has concentrated on the design of energy and computationally efficient algorithms and routing protocols with application domain restricted to simple data-oriented monitoring. In this paper, we presented a comprehensive analysis on WSNs routing with key challenges for development of protocol designs. At last we discussed some open issues for future directions in WSNs for research contributions. \end{abstract}  \begin{keyword} Wireless sensor networks, self-organization, scalability, routing protocols   \end{keyword}  \end{frontmatter}  \linenumbers  %% main text  \section{Introduction}   Wireless Sensor Networks (WSNs) contain self-configured, distributed, autonomous and resource empowered sensor nodes that monitor physical or environmental activities, such as humidity, temperature, sound, vibration or pollutants in a specific area of operation\cite{akkaya2005survey}. Sensor nodes \cite{abbasi2007survey}cooperatively \cite{al2004routing}pass their sensed data through the wireless\cite{bi2010ant} network to a main location, known as sink or base station where the data can be monitored and analyzsed for decision making.   \subsection{Subsection One}    \subsection{Subsection Two}    \section{References}   \bibliographystyle{model1-num-names} \bibliography{Ref}     \end{document}

How can I make things link url references, my index, table of contents, and cross references clickable links in documents produced by LaTeX? I generally use pdflatex to produce my documents.


I frequently find myself on the bus or train with time to review some edits, first time posts, etc.   However, it's not possible to do this on the mobile interface, and the desktop interface is very cumbersome to use on my phone. The modal dialogs slide around, I sometimes hit the wrong button, and the screen zooms halfway across the page when a text box gets focus.  I've seen other questions requesting a general mobile app, and the ability to close / flag posts on mobile, but nothing about reviewing on mobile.  When it's convenient for me to do, I don't always have my laptop, so I'd like to request a mobile interface for review.

The other day I was looking at Stack Overflow on my Android phone. All is made very nice and all, but I could not find the Review button/link. Is it being implemented, did I miss it, or it is not available?


I tried rcconf and update-rc.d but transmission-daemon starting each time i boot the system.

I read about how to enable and disable services in Ubuntu and it seems that there are different possibilities to manage them.  The first method I found is update-rc.d to add new services to startup, which aims on the /etc/init.d folder and its contents.  The other one I found is to edit .conf files in the /etc/init folder.  What's the recommended way to enable / disable / add services and why?  Could you please give a short bulletproof step by step example on how to add a service in Ubuntu and enable and disable it?


So for context: I'm trying to create a simple chess program in python with pygame (2.0.0). Since I don't want to create every single of the 64 tiles manually I am looking for a way to create them using a function. Since in chess tiles are named from a1 to h8 (files and ranks) I want the objects to have this kind of names (a1, a2,...). The tile-class is until now very simple: class tile:       def __init__(self):         self.piece = None  Then I made two lists: one for the files and one for the ranks. Then two for-loops (one in another) so that for every single combination it would create a tile-object: files = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'] ranks = ['1', '2', '3', '4', '5', '6', '7', '8']  for f in files:     for r in ranks:         f + r = tile()  Now my problem: python doesn't allow this ;( I want to create 64 tile-objects with names from a1 to h8. Is there any way for this?

Suppose I have a python object x and a string s, how do I set the attribute s on x? So:  >>> x = SomeObject() >>> attr = 'myAttr' >>> # magic goes here >>> x.myAttr 'magic'   What's the magic? The goal of this, incidentally, is to cache calls to x.__getattr__().


I have tried to look at many answers to this question, since it is a rather common one, but with no satisfactory answer up until now. The truth of the story is: Hermione was crying in the girls bathroom because of Ron's comments and didn't know about the loose troll, which is why Ron and Harry came to warn her. The story Hermione tells: She read about trolls and thought she could take it on by herself. Harry and Ron probably saved her life. What seems to be the ideal story: Simply leave out the part about crying because of Ron's comments, there are other obvious reasons why one might be in a bathroom. Possible answers that could make sense:  The bathroom she was in wasn't the closest one to the great hall, so she would have had to explain why she was in that particular bathroom. Apparently she has been there "all afternoon", so perhaps that's why she needed to make sure not to reveal that she has been crying because of Ron and instead say she went looking for the troll. But this would raise the question of why she assumes the teachers would know for how long she was already in the bathroom. Hermione assumed that Ron and Harry wanted to fight the troll. She didn't know they came to save her so she decided to take the blame instead.  Do any of these answers make sense? If not, I don't see any reason why she would lie. A common answer to this question is "She wanted to shift the blame onto herself" but she wouldn't really accomplish that since Harry and Ron still disobeyed teachers orders in order to save Hermione regardless of her motives.

In Harry Potter and the Philosopher's Stone, Hermione is in the toilets when Harry and Ron lock in the troll. She lies and says that she went looking for the troll. Why? She could have just said that she was in there because she needed the toilet (she was allowed to be, it's a girls' bathroom) and Harry and Ron came to save her.   Is there a reason she lied?


I am doing something very simple. I'm trying to retrieve a node from a small XML file.   <?xml version="1.0"  encoding="UTF-8" ?> <SAMLConfiguration xmlns="urn:componentspace:SAML:2.0:configuration">   <IdentityProvider Name="IdpNameInSPForIsuer"                     Description="SecureAuth"                     LocalCertificateFile=""                     LocalCertificatePassword=""/>    <ServiceProviderProfiles>     <ServiceProvider NameIdentifier ="SPIssuerName"                      ExpectsSignatureVerification="true"                      ExpectsSignedResponse="false"                      Certificate="sharedpubliccsert.cer"                      DigestMethod="SAMLIdentifiers.DigestMethods.SHA1"                      SignatureMethod="SAMLIdentifiers.SignatureMethods.RSA_SHA1"                      SingleLogoutServiceUrl="https://serviceprovider/slo"                          SendResponseBy="HTTP-Redirect" />    </ServiceProviderProfiles> </SAMLConfiguration>   I am trying to get the ServiceProvider. Below is the C# code I have:     string parent = "ServiceProviderProfiles";    string children = "ServiceProvider";      var nodePath = string.Concat(@"//", parent, @"/", children);   var xmlNode = xmlDocument.SelectSingleNode(nodePath);   When I debug, the xmlNode is null. What problems with my code is causing the xmlNode to be null?

I've got an XML document with a default namespace. I'm using a XPathNavigator to select a set of nodes using Xpath as follows:     XmlElement myXML = ...;   XPathNavigator navigator = myXML.CreateNavigator(); XPathNodeIterator result = navigator.Select("/outerelement/innerelement");   I am not getting any results back: I'm assuming this is because I am not specifying the namespace. How can I include the namespace in my select?


A person with a cold will have nasal mucus in their nose building up. They continuously try to forcefully inhale the liquid mucous substance in the nose by breathing it in so that the nose stops running for a moment.  I would like to tell them not to that as over time it will cause headache. I want to know if there is a word for inhaling phlegm. For example       Don't ________, because it will cause headache.

My mom and I say 'soup' like: "Why are you souping the snot back up your nose?" But I realise that this is not accurate. So what's the word?