pip got corrupted after uninstalling python packages

I uninstalled some python packages in ubuntu using sudo pip uninstall packagename and after that my pip got corrupted. When I do pip -V its showing this     from pip._internal.download import PipSession   File "/usr/local/lib/python2.7/dist-packages/pip/_internal/download.py", line 15, in <module>     from pip._vendor import requests, six, urllib3   File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/__init__.py", line 97, in <module>     from pip._vendor.urllib3.contrib import pyopenssl   File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/urllib3/contrib/pyopenssl.py", line 46, in <module>     import OpenSSL.SSL   File "/usr/lib/python2.7/dist-packages/OpenSSL/__init__.py", line 8, in <module>     from OpenSSL import rand, crypto, SSL   File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 118, in <module>     SSL_ST_INIT = _lib.SSL_ST_INIT AttributeError: 'module' object has no attribute 'SSL_ST_INIT'   The first thing I did to solve this problem is to reinstall pip itself so I did  sudo apt remove python-pip --purge sudo apt install python-pip   But pip -V gives the same error. So I then again completely removed pip without reinstalling sudo apt remove python-pip --purge; sudo apt autoremove.   Now I have completely purged pip from my system but even after this when I did pip -V I am getting same error?


If $AA^T$ is the zero matrix, then $A$ is the zero matrix

Let $A$ be a $4 \times 4$ matrix. Show that if $A^TA$ or $AA^T$ is the zero matrix, then $A$ is the zero matrix.   I feel very close to solving the problem so far. I have said that  $$[0]_{ij}=\sum_{k=1}^4 [A]_{ik}[A^T]_{kj} =\sum_{k=1}^4 [A]_{ik}[A]_{jk} \qquad \text{for all }i,j \in \{1,2,3,4\} $$  and proven for the case if $i=j$. However, I cannot seem to find a good way to prove it to be true if $i\neq j$.


i got whole of my path deleted and after which i shutdown my pc. Later when i wanted to add another environment variable i found that whole of my path was empty  Is it possible to restore it?


i can't place or break blocks in minecraft

I started a new survival world and switched to creative just to build my house. When I was done, I switched back to survival. But after I switched back, I found that even when I checked and aimed and held my click, I could not break or place blocks.   I am super sad because I built a huge house and now I can do basically nothing... How can I fix it?  I have tried switching modes and shutting my computer down, but nothing helps.


the two bits of SQL below get the same result  SELECT c.name, o.product   FROM customer c, order o   WHERE c.id = o.cust_id   AND o.value = 150    SELECT c.name, o.product   FROM customer c   INNER JOIN order o on c.id = o.cust_id   WHERE o.value = 150   I've seen both styles used as standard at different companies. From what I've seen, the 2nd one is what most people recommend online. Is there any real reason for this other than style? Does using an Inner Join sometimes have better performance?  I've noticed Ingres and Oracle developers tend to use the first style, whereas Microsoft SQL Server users have tended to use the second, but that might just be a coincidence.  Thanks for any insight, I've wondered about this for a while.  Edit: I've changed the title from 'SQL Inner Join versus Cartesian Product' as I was using the incorrect terminlogy. Thanks for all the responses so far.


TikZ - game tree representation with continuum of moves

I have been using TikZ to draw game-trees for my game-theory lectures (mostly using the automata package) but I could not figure out how to draw an arc across the edges the leave a given node. When we want to denote that a player has a continuum of actions available at a node, we usually draw an arc across the edge leaving such node. For example see the arc crossing the edges that leave the first node in this picture:     Any suggestions on how I could try to implement this in TikZ? Thanks!


How can I have a URL like www.example.com/about?language=ja to set Japanese for the page?

I've enabled the Locale and Content Translation module but am having trouble understanding how to do something that it seems should be working.  Basically I have a page, we'll say '/about' and it's in English.  I click translate, I have a few languages enabled, so I click to add translation for Japanese. It brings up the interface for making a new page. I change some stuff to Japanese, and set the URL alias to be /about ('about') like the english page.  I've setup my language options to use the "Session" detection method.  The result I'm wanting to achieve, but not getting is to have:  www.example.com/about -- to go to english (this works) www.example.com/about?language=ja -- to go to the Japanese translation, this does not work, it just loads up the English page.   It seems like this would be the normal functionality so I feel like I'm missing something here.


Textbook has a strange section on absolute value that I don't quite understand

My textbook says $|a| = -a$ for $a \le 0$.        What does it mean by this? I'm confused and think that the absolute value of a negative number like $|-5|$ would be positive $5$?


Debian - how to run a script on startup as soon as there is an internet connection ready for use?

I am running Debian 7 Wheezy and I need to start some screens on startup as soon as there is a fully functional internet connection. However, not, if the internet connection broke and was connected again. So only on the first functional internet connection after boot.  Could you please post a dummy script for this and tell me where to put it and make it be executed under the given conditions?  The script only needs to start the screen and then terminate but the screen should continue.    EDIT I have already heard of the /etc/network/if-up.d/ folder. But how can I make sure that the script is not executed again if the internet connection is lost and then re-established?


Is voting ever locked for questions/answers?

I just noticed I was able to vote on a question that was closed.  I found that a bit strange. Is there any time when you can't vote on a question/answer? i.e. does it ever get locked also?


How can an electron have angular momentum when it doesn't orbit the nucleus?

Since electrons do not orbit the nucleus like particles, and instead have a probability to "exist" around the nucleus, how can they have an angular momentum as if they move at a certain velocity around the atom?   Also, why does this force the electrons probability density into distinct shapes?


Disable "Show position of the mouse when the Control key is pressed" in 13.04

In version 12.10 there was a setting under System Settings > Mouse & Touchpad to "Show position of the mouse when the Control key is pressed”. While using 12.10 I enabled this option.  I have since upgraded to version 13.10, and this setting appears to have disappeared.   How can I now disable this? It is interfering with the use of the control key in a number of apps, such as VirtualBox.  I'm quite happy to use the terminal or edit a settings file if that is the best (only) way to do this. I really (!!) don't want to have to reinstall just to reset this one option.


I want to make a clay material like in this photo. Not a clay render, a clay material; something for my sculptures I model in Blender. How could I make something like the material in this image?    I have been trying to make this material for hours and it's driving me crazy. please help!  this is what i have gotten after playing around with nodes:


How can I automatically shutdown the system after a specific time?

How can I automatically shutdown the system after a certain customizable time?


Is address line 1 + address line 2 an anti-pattern?

The typical address block on a form contains two fields for address:  Address ------------------------------- |                             | -------------------------------  Address Line 2 ------------------------------- |                             | -------------------------------  City ------------------------------- |                             | -------------------------------  State ------------------------------- |                             | -------------------------------  ZIP ------------------------------- |                             | -------------------------------   Are two lines for the address really necessary? I've never personally had a use for the second line and, at best, it's an empty field, and, at worst, it screws up my browser's form auto-fill settings. I did an informal office survey and heard the same from others--that they've never needed it.   Are there real world scenarios where it's needed?  I understand that it's often seen as an apartment field, but even that can be written as one line (and something I've done in the past):     1234 5th Avenue North, Apt 45   Is this just an old habit/anti-pattern that we should consider breaking?


Unable to replace Null values using Python parser of ArcGIS 10.0 Field Calculator?

I'm using the following python code to replace Null values by 0, using field calculator:  def nulls(p1):  if p1 is None:     return 0  else:     return p1   But nothing happens, Null values stay. I'm using ArcGIS Desktop 10.0.


Should I ask for help to forming question in metas?

Sometimes I have a vague idea for a question, but asking it right away may result in a confusing or unclear question, or after receiving answers I realize that I haven't asked the right one. Sometimes this happens even when I have researched on it. In such case, is it OK to ask the community first to help me forming the question in metas? This will reduce the time for editing back and forth, or in the case of already getting answer, will reduce the time they have to edit theirs for me.  The question  does not have answer about meta specifically. In chat you can only discuss with some people, while in metas it is less fleeting and will receive more attention. If that's a bad thing, then one can argue the opposite that discussing on closed questions should be happened in chat too, not metas.


How efficient is the .find() function in JavaScript? Is it faster than .map() or .forEach()?

Is using .find() in JavaScript inefficient as compared to using .map() or .forEach() ?  For example, in case of an array of objects :  var arr=[{name:"vishek",ID:222,subjects:["science","maths","politics"]}]  For such an array, is it efficient to use .find to find a particular object or .map()?


How do I make this sphere follow this bezier curve

Please help I cant find how to move the ball along the path! any help would be huge thanks!


Ubuntu 18.04 update problem 404 Not Found [IP: 91.189.95.83 80]

I can't update my Ubuntu 18.04 LTS  This is error message:    How can I solve this? I try to change server main to US. But I got same error message.


Are these sentences both structured correctly?

I know what is the meaning of this.      I know what the meaning of this is.   If the first sentence is considered correct, can someone please explain the reasoning?  Edit:  The answer of the "Changing Subject and Verb" post illustrates my question, not the answer. Another example:     To know whether you are dealing with the main clause or an embedded clause, you have to think about what is the main verb of the whole sentence.   Compared to:     To know whether you are dealing with the main clause or an embedded clause, you have to think about what the main verb of the whole sentence is.


Suppose $F_1,F_2$ is closed in $R^n$,and $F_1\cap F_2=\emptyset$,proof there exist$G_1,G_2 $are open set,such that $G_1\cap G_2=\emptyset$,and $F_1\subset G_1,F_2\subset G_2$  Attempt   Suppose $a_n=\frac{1}{n}$ And $F_i\subset \cup _{x\in F_i}B_{a_n}(x)=G_i,i=1,2$  Then I want to use Contradiction,I can get $x_n\in G_1,y_n\in G_2,and z_n\in G_1\cap G_2$,satisfy $|z_n-x_n|<\frac{1}{n},|z_n-y_n|<\frac{1}{n}$  I don’t know what should I do next


Is there a system in place to prevent new users asking, answering and accepting answers to each others' off-topic questions?

Normally new users are not allowed to up-vote until they gain a bit of reputation by receiving up-votes or accepts from the community of a site.  But this has a weak point that is being exploited:     A number of new users post, answer, and accept each others'    off-topic questions before we can close them (in less than 5 min).    Accepting each others' answers gains them enough reputation to    start up-vote each others' posts.   We are closing them and the moderators clean up afterwards but  this keeps happening over and over again and becoming frustrating  to the extent that I think a systematic solution might be required. Is there a system to prevent this kind of circumvention of  the reputation requirements using accepts by new users?  One possible solution might be to change the system so accepts from users who do not have enough reputation to up-vote  do not give any reputation (at least until the answer gets an up-vote).


Pass a PHP string to a JavaScript variable (and escape newlines)

What is the easiest way to encode a PHP string for output to a JavaScript variable?  I have a PHP string which includes quotes and newlines.  I need the contents of this string to be put into a JavaScript variable.  Normally, I would just construct my JavaScript in a PHP file, à la:  <script>   var myvar = "<?php echo $myVarValue;?>"; </script>   However, this doesn't work when $myVarValue contains quotes or newlines.


General Formula for Number of Surjective mappings from the set $A$ to a set $B$.

How can I prove that the number of surjective mapping from the set $A$ to a set $B$ is $\sum\limits_{r=1}^n(-1)^{n-r} \binom{ n}{ r}r^m $, where $|A|=m$ and $|B|=n$. I can't get any idea how to prove it. Is it possible to prove it?


I recently find a limit that shows $\pi$:  $$\lim_{n\to \infty }\, 2^{n} \underbrace{\sqrt{2-\sqrt{2+\sqrt{2+\cdots +\sqrt{2}}}}}_n= \pi$$  The problem is that I cannot know what the limit says I talk about positive and negatives.With what order are they?


Mysql select splitting the comma separated values

the data "123,456,332,123,567,448......"   how to select the data and get the list like :     id ,count(*)      +---+-------+-------+ |   |  ID   | Count | +---+-------+-------+ | 1 | 123   | 2     | | 2 | 456   | 1     | | 3 | 332   | 1     | | 4 | 567   | 1     | | 5 | 448   | 1     | +---+-------+-------+     I try to use   from              (select 1 n union all select 2 union all select 3 union all                  select 4 union all select 5 union all select 6 union all                 select 7 union all select 8 union all select 9 union all                  select 10 union all select 11 union all select 12 union all ...   but if the comma over 1000 or more, how to get the split list ?  ---- edit GMT +8  3/14 14:35 ---  I had look up this post and the solution did not match.    if I could split that field and return a single element from the resulting array, that would be what I'm looking for. Here's what I mean in magical pseudocode  even the solution can try to       SELECT 1 + units.i + tens.i * 10 AS aNum FROM (SELECT 0 AS i UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) units CROSS JOIN (SELECT 0 AS i UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) tens   but if we don't know how many comma that i can't get the right way


How to tell the heat, or at least fan speed, of a machine

Is there a way in which I can tell how hot my computer is? Or at least how fast my computer's fan is going? Because if my computer's fan knows how fast and when to go, then surely my computer knows the heat of my computer?    OS Information:  Description:    Ubuntu 15.04 Release:    15.04


My lens is capable of f-stops higher than the label

I searched on here and I read everything on this page:   But I still don't understand what's going on with my lenses and how they are labeled. I have a couple of lenses, one is labeled as "3.5-5.6/18-55" and I know that means "F-stops from 3.5 to 5.6 and focal length of 18mm to 55mm" but what I don't understand is I can set the aperture to numbers outside that range, regardless of the focal length. For example I can set the camera (Sony Alpha 65) to F/22 and when I shoot the image, it's obviously F/22.  SO, if the labeled numbers are not a limit, what are they for? What is stated on the web page is not correct, where he says "when you zoom out to 18mm you'll be at F/3.5 and when you go in to 55mm you'll be at F/5.6" - because I can be at whatever F-stop I want, at any point along the zoom range.  OK, after posting I found this in the related posts:   That kinda answers my question. So, to be clear, the numbers are the lowest you can go at each zoom extreme?


Showing continuity of a real valued function

Let $S=[0,1)\cup [2,3]$ and let $f:S\to \mathbb{R}$ be strictly increasing such that $f(S)$ is an connected subset of $\mathbb R$. How to show that $f$ is continuous?  $f(S)$ is connected means it is an interval. Also $f$ is one-one. But I couldn't proceed further. Please suggest!


How do I replace the last occurrence of a character in a string using sed?

How do I replace only the last occurrence of "-" in a string with a space using sed?  For example:  echo $MASTER_DISK_RELEASE swp-RedHat-Linux-OS-5.5.0.0-03   but I want to get the following output ( replacing the last hyphen [“-“] with a space )  swp-RedHat-Linux-OS-5.5.0.0 03


ArcPy: Selecting feature class by attribute then copy selection to new feature class

Using ArcPy I want to make to do a selection on a feature class by field to select everything 0.1 or greater, then copy the selection to a new feature class. However, the output of my following code is exactly the same as the input and includes values under 0.1. input_fc = r"C:\Geoprocessing\Model.gdb\input_fc" output_fc = r"C:\Geoprocessing\Model.gdb\output_fc"  arcpy.SelectLayerByAttribute_management(in_layer_or_view=input_fc, selection_type="NEW_SELECTION", where_clause="Field1 >= 0.1") arcpy.CopyFeatures_management(input_fc, output_fc)  is there a step I am missing?


Can I force VGA signal output even when xrandr shows 'disconnected'?

My notebook is connected to a HDTV through a KVM Switch (one other notebook also connected to the same HDTV). The problem seems to be that Ubuntu doesn't recognize the HDTV to be turned on and therefore doesn't enable the VGA output. As far as I understand it has something to do with EDID information not being send trough the KVM Switch.  xrandr won't enable the VGA output through xrandr --output VGA1 --auto, it just keeps showing as disconnected.  Can I somehow force the VGA port to send a signal?  My Graphics Controller:  Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03)


Add an audit log to record when particular question enters and leaves hot list

The  displays a constantly changing list of 100 questions, since it deals with time since recent activity. But are changes in this list ever recorded anywhere for posterity (or data mining, or to use in studies like , , , , ,  etc)? Can one, perhaps someone with sufficient data access privileges, look at a certain question and see when it was hot, in the form of a graph or something? As far as I can tell, history of this ever-changing list :  We currently do not record anything about when a question enters/leaves the hot question list. The list is calculated on the fly each time (and heavily cached)...  This is a feature request to add an audit log or something somewhere for that. I don't know how often is the list actually updated, but for data study purposes I think it would be okay to record changes once in an hour or two or, if even this would be too difficult, at least once a day would probably be acceptable.  Note there is a similarly looking question:    It only looks similar (partly because I simply modeled wording above after it:) but is actually different. As opposed to current request which asks essentially for timeline of changes in a list of 100 elements (question IDs), older one is about much much more detailed data, namely about recording hotness score of all (!) questions all (!) time, if I read it correctly. Not only it would be much harder to maintain and analyze such data, but its very usefulness became quite questionable after , meaning that hotness score became simply ignored to a large extent.  Another older question which is indeed strongly related to current one:    The difference is that according to , that older request somehow involves fairly cumbersome (real time?) tracking of vote counts, which is totally irrelevant here, as current request is limited strictly to "timeline of changes in a list of 100 elements", possibly recorded "once in an hour or two or... at least once a day".


when I try to use sudo -I command, I get this error:  sudo: /etc/sudoers is owned by uid 33, should be 0 sudo: no valid sudoers sources found, quitting sudo: unable to initialize policy plugin   so I tried to use pkexec chown -R root:root /etc/sudoers and I get this error:  polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie ==== AUTHENTICATION FAILED === Error executing command as another user: Not authorized  This incident has been reported.   Does anyone know what to do with this?  EDIT:  I think it is because I ran sudo chown www-data:www-data / by a mistake, but I stopped it after few seconds.  What do you think, I should do with that?


I'm looking for a commonly used symbol that denotes a set of vector fields. It looks like an \st{$\chi$} (using the soul package, that is, \usepackage{soul}, but doesn't look so artificial.  Can someone help me? Also, this is my first posting on this SE so I'm not entirely sure of how to format things.  Thanks!


What does it mean for "A is confounded with B"

Can you give me an example for one variable being confounded with another? (I've read the tag wiki for "confounding" but I'm still confused.)


Do Cantrips use your character level or class level?

Cantrips seem to be the only type of spell that cares only about your class level. However, in the multiclassing section they are not mentioned, does this mean that cantrips use your character level, instead of your class level?  Does this mean a Warlock 2 / Fighter 15 can cast an Eldritch Blast with 4 beams just like a level 17 Warlock?


Build a (normal?) distribution from $n$, quartiles and mean?

I have some data that is described by $n$, quartiles (+ additional quantile point) and the mean.  Is it possible to rebuild or model this distribution from these statistics?  As the median and the mean are not the same, there is at least some skew, but otherwise, I would assume the data to be normal like.  Edit:  This was marked as a duplicate, but in the other questions I found while searching, none of them included the information regarding the mean as a data point to recreate the distribution.  Because of that additional parameter, I wondered if it made the estimation possible.  In short, the affect of having the mean was not apparent from the other answers related to the question.


Align horizontally side by side equations

I would like to align these two side by side systems of equations horizontally. I tried to do this like this  \documentclass[12pt,letterpaper]{article} \usepackage{amsmath} \begin{document} \begin{center} \begin{tabular}{p{4cm}p{4cm}} {\begin{align} &\alpha =\alpha_{1}=\sqrt[3]{19}\nonumber \\ &\alpha_{2} =\varepsilon\sqrt[3]{19}\nonumber \\ &\alpha_{3} =\varepsilon^2\sqrt[3]{19}\nonumber \end{align}} & {\begin{align} &\beta =\beta_{1}=\frac{1+\sqrt[3]{19}+\sqrt[3]{19^2}}{3}\nonumber \\ &\beta_{2}=\frac{1+\varepsilon\sqrt[3]{19}+\varepsilon^2\sqrt[3]{19^2}}{3}\nonumber \\ &\beta_{3}=\frac{1+\varepsilon^2\sqrt[3]{19}+\varepsilon\sqrt[3]{19^2}}{3}\nonumber  \end{align}} \end{tabular} \end{center} \end{document}   and I get this    How can I align all beta's horizontally with alpha's?


Student's written calculations beat other students using calculators

I read an Analog story in the 1970's about a student who used a pencil and paper to figure out the math test question of the day and he finished the problem before anyone else in the class who were using their calculators to answer the problem.  The student learned this AMAZING TRICK from his grandfather.  Does anyone recall what this story is titled and written by which author?  The Cartoon "LUANN" has a similar theme in today's Sunday Paper - 1/25/15.


Worldwide 1024x768 is still the most common screen resolution. Why they had chosen the width as 1024 and not a user remembrance number like 1020 or 1030?


Setting a default value for property that is mutable in C#

I have a property   public int active { get; set; }   That in my db has a default value of 1. I would like to have this property default to 1 if not otherwise specified  public partial class test {     public int Id { get; set; }     public string test1 { get; set; }     public int active { get; set; } }   I saw that in c# 6 you can do  public int active { get; set; } = 1   But I am not using c# 6 :(. Thanks for the advice. (Very, very new to c# / OOP)


Why did I get a welcome message informing me I'd get a badge for taking the tour, if that badge is not active?

When I signed up I received a welcome message specifically indicating I should take the tour to earn my first badge:     Clicking the message takes me directly to the .  However, as   , the 'Informed' badge is not active here on meta.  Shouldn't the wording of the welcome message be altered if a user signs up on a site which does not use this badge?


Intuitive reason why jointly normal and uncorrelated imply independence

It is well-known that if two random variables are jointly normal and uncorrelated, then they are independent. Does anyone have an intuitive reason why this is true? Explanation in terms of data is greatly appreciated.  Updates:  After seeing the answer by @kjetil b halvorsen, I feel I should give some more details. As far I know, that result (uncorrelated implies independence) is true if the variables are Bernoulli or they are jointly normal. I would like to stress that I completely understand the math behind the truthfulness of the mentioned result. When they are jointly normal, $\rho = 0$, so the joint density will factor into two, one a function of $x$ alone and another function of $y$ alone, hence independent. What I am looking for is some intuition why is this the case? For example, in case of Bernoulli, the only possible data are $(0,0), (0,1), (1,0), \text{ or } (1,1)$. So, if there is no linear relationship between them (uncorrelated), then there is none (independent)! I am just wondering whether there is anything like this?


In his online lectures on Computational Science, Prof. Gilbert Strang often interprets divergence as the "transpose" of the gradient, for example  (at 32:30), however he does not explain the reason.  How is it that the divergence can be interpreted as the transpose of the gradient?


Finding out which app is using the webcam

Yesterday I was working on my laptop. Suddenly I noticed that the indicator light of the webcam was on, despite the fact that I wasn't making a video call or using the webcam in any other way at the moment.  It freaked me out.  It freaked me out that some unknown application on my computer was using my webcam without my permission, and possibly sending that video stream to god knows where on the Internet.  In the end, it turned out to be Skype which was in the process of crashing. (Despite me making no calls at the time.) So that story ended well.  But next time I see the webcam indicator light, I want to be ready. I want to be able to know exactly which app is using the webcam so I could destroy it.  Does anyone know how I can find out which app is using the webcam?  (I'm on Windows XP.)


Why cp --preserve=links doesn't work? I want to copy some symbolic links.From man page:     --preserve[=ATTR_LIST]   preserve the specified attributes (default: mode,ownership,timestamps),   if possible additional attributes: context, links, xattr, all*   On my CentOS 3.10.0-693.el7.x86_64,it doesn't work.  Following is my steps:  [root@ beau]# ls -l total 4 lrwxrwxrwx. 1 root root 11 Dec 2 21:49 bar.txt -> foo/bar.txt drwxr-xr-x. 2 root root 4096 Dec 2 21:41 foo [root@ beau]# cp --preserve=links bar.txt bar1 [root@ beau]# ls -l total 4 -rw-r--r--. 1 root root 0 Dec 2 23:08 bar1 lrwxrwxrwx. 1 root root 11 Dec 2 21:49 bar.txt -> foo/bar.txt drwxr-xr-x. 2 root root 4096 Dec 2 21:41 foo   My questions is :Why the option '--preserve=links' doesn't work?


What are good test shots for finding out the capabilities of a camera?

I have a range of cameras from a (frankly awful) kiddie camera to a hybrid (Olympus Pen) and I want to take some pictures to test their (comparative) limitations.  So I want to take the same photos with each camera, load them on to my computer, and be able to say: "This is clearly better than that" or "There's not a lot to choose between them" (so it's a rough comparison).  Also, in the absolute: "Never use the kiddie camera for photographs that ..." (to be honest, I suspect that that one could end after the fifth word).  Thus my question: What sort of photographs should I be taking for this experiment, and what sort of feature will each photograph test?  To add a sniff of motivation, I bought the kiddie camera for (surprisingly enough) one of my kids to get a bit of practice with taking photographs.  But it is absolutely awful and seems to only take reasonable pictures with lots of light and the subject an exact distance from the lens.  I recently picked up a (very) cheap compact with the intention of swapping it for the kiddie camera (with suitable admonitions that this one can't be dropped) but I'd like to test it myself before handing it over as replacing a rubbish camera with a rubbish camera won't get me those highly coveted Daddy Points.  So in this particular test, I want to compare those two with (maybe) the Olympus providing some sort of "gold" standard (I'm aware that by the standards of this site, the standard provided by the Olympus won't be quite gold, but then iron pyrites is underrated in my opinion).  But I'm also interested in the wider question of taking test shots myself to compare cameras to learn more about what each one is capable of (or rather, to learn what each one is capable of when I'm taking the photos - which is why I'm not interested in online comparisons of the cameras).


Regex to extract text between parenthesis paired with asterisk

This is a slightly different from similar posts in that the parenthesis are paired with an asterisk.  example input:     yada yada (* need to grab this text *) yoda   I thought  could be altered for this but my attempts fail.         //Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)"); //original         Regex regex = new Regex("\\(\\*(?<TextInsideBrackets>\\w+)\\*\\)"); // my attempt         string incomingValue = "Autocycleprestartcase := 20;   (* Yayitme ve Konveyoru bosaltabilir *)";         string insideBrackets = null;         Match match = regex.Match(incomingValue);         if (match.Success)         {             insideBrackets = match.Groups["TextInsideBrackets"].Value;         }   Suggestions?  Also, I'd like to remove the enclosed text, with the enclosing parethesis/asterisk pairs, from the input line.  So the output of above would give me     yada yada yoda   and the value     need to grab this text   Thanks


How can I typeset a lowercase circled r (Unicode character U+24E1)?

I would need to typeset in LaTeX the following symbol: ⓡ, which is described here:    This symbol can be of general use for referring to a randomized order of coauthors in a paper, cf. Ray, D., & Robson, A. (2018). Certified random: A new order for coauthorship. American Economic Review, 108(2), 489-520.  This is not the standard \circledR symbol, but rather something more like \circledr. However, it does not seem to exist in LaTeX.   Could someone help me design this, without having to adopt a font that recognizes this unicode character in LaTeX?


How to search birthdate using sql query?

I want to search Date of Birth from my sql server database table. Problem what i am getting is the year of DOB will be different and will be latter than current year. If i want to get customer list whose birthday will coming in next 7 days same as facebook birthday reminder.  I have tried to convert smalldatetime to varchar and used LIKE statement with '_' wild card character. for example Convert(Char(10),DOB,103) LIKE "__/02/____'.  but, it gives me list of customers whose DOB is coming in current month. Also it shows me those data whose birthday has gone previously on current month. I want to only those data whose birthday is coming on next 7 days.  My application has developed in C#. if possible to get appropriate result using DataTable or DataView then please suggest me.


I seen in many texts for set theory that ZFC forms a foundation for most of math, e.g. analysis, topology, algebra, etc.  Are they any fields of mathematics that cannot be built on ZFC?


Accurate comparison of two variables of type float in C++

What can I do to compare two variables of type float accurately in C++, one being initialized at the time of declaration and the other being computed through the program?   When I am comparing two variables having value either 0.5 or 0.25, the program is showing the desired output but when I am comparing two variables having value either 0.333333 or 0.666667, the program is not showing the desired output. Will you please tell me where I am going wrong? Please help me in writing the correct piece of code. I am a novice and it will be a great experience to learn from you. Thank you for your concern. Here is the code with some of the outputs:


How does the speed of electrons change around a circuit?

I have been thinking about ways of teaching electronics and I'm wondering if the following is true...  For starters, when we talk about voltage as energy per unit charge, is this energy manifest simply as the kinetic energy of the electron?  So, all other things being equal, will the electrons coming out of a 4 volt battery will have twice the velocity of electrons coming out of a 1 volt battery because of ${1 \over 2}mv^2$?  This would seem to imply that the voltage drop across different parts of the circuit is essentially a comparison of the electron speeds at those points.  Furthermore doesn't this imply that the electrons are nearly halted by the time they reach the positive terminal of the battery? This makes intuitive sense to me, it seems pedagogically sound, and it provides an explanation for how electrons "know" to give up their energy across the circuit -- electrostatic repulsion communicates later resistances to earlier parts of the circuit.  How much of the above is correct? The one things that makes me suspicious is that, in this picture, electron density at the positive terminal of the battery is very high, and repulsive forces would prohibit this. On the other hand, if the Joules per Coulomb are not coming from kinetic energy, then what? The field? But wouldn't that just dissipate as light?  Something is wrong but I don't know what.


I have a data set where I am interested in the regression line the best explains the upper bound of that data. As an example the subset of data 'df2' from 'df' below represents the best 4 points describing the upper bound that all the data lies under:  df <- data.frame(x = c(38,  45,  78,  88,  99,  103, 117, 117, 120, 148),               y = c(256, 226, 185, 198, 187, 89,  167, 160, 138, 85)) df2 <- data.frame(x = c(38, 88, 99, 117), y = c(256, 198, 187, 167)) plot(df) abline(lm(y~x, df)) points(df2, pch = "x", col = "red") abline(lm(y~x, df2), col = "red")     The nature of the data is that 4 data points on upper bound and with reasonable spread should return an R^2 > 98%. Ultimately I am interested in the x- and y-intercepts of the red regression line depicted in the plot. Any suggestion for a function or method that can achieve this would be greatly appreciated.


How to get the name of a method in a class

How to get the specific name of the current method in Ruby?  Example:  class Pages   def home     @title = self.name   end end   I want to get this result:  p = Pages.new p.home # it must print "home"


What does this "(base)" mean in my terminal prompt?

(base) fedaa@fedaa-Satellite-L50-B:~$ cd molecules/   What does this (base) mean in my terminal prompt?  I just found it and I have no idea what it refers to.


Account doesn't have permission to suggest edits

I tried to edit  on SuperUser using the SE Andriod app (v1.0.51) and got the following error in the red bar at the top:     Account is not allowed to suggest edits.   I get the same error when trying to Preview the edit as well.  I can (and did) successfully submit the edit from the website.


Can we make it possible to tag more than one user in the same comment?

I know there must be a good reason why the one tag limit must be in place, but I can't really see a good reason why. From my perspective, I often would like to reply to two or more users with the same message, but to do so I have to write to separate comments.   Could someone please enlighten my as to why the one tag limit exists, and/or can we make it possible to tag multiple users in a comment?


Suggested Edit (User who has privileges to approve tag wiki edits)

Currently I have privileges to approve wiki tag edits in   Pre-Requisite  User should have reputation score more than 5000  Steps to reproduce   Edit a wiki tag From that moment onward you can see following     Clicking on that gives


Rounded corners on only one side of a TikZ node

How can I make rounded corners on one side of my node (only right, only left)?  \documentclass{minimal} \usepackage{tikz} \begin{document}     \begin{tikzpicture}         \node [fill=gray, rounded corners=10pt]{          };     \end{tikzpicture} \end{document}


Why Is the landscape not toxic in The Walking Dead?

As clearly defined in Life After People Nuclear Power plants would melt down days to weeks after people disappeared. Now, I seriously doubt that anybody would stick around to even try to operate the reactors when the crap hit the fan......so since America alone has over 100 reactors so in theory the good old USA should be a desolate, radioactive death-zone ass well as filled with the undead. Also why didn't the huge chemical spills that would have occurred after and during the panic effect the survivors at all?  My question is this: Why didn't the world become totally inhospitable after the mass outbreaks.


Why is the mean function in Gaussian Process uninteresting?

I have just started reading about GPs and analogous to the regular Gaussian distribution it is characterized by a mean function and the covariance function or the kernel. I was at a talk and the speaker said that the mean function is usually quite uninteresting and all the inference effort is spent on estimating the correct covariance function.   Can someone explain to me why that should be the case?


I found the website http://stackoverflow.xluat.com/questions (edit: do not go there, the site is possibly malicious now) and it seems to be the  version of Stack Overflow.  But I cannot find any trace or information about it on SO or SE. Does anyone know anything about it?


On subsurface I'm getting unexpected result like on     but I would like to receive result with smooth surface (not collapsed faces)  What could be wrong in my model ?


How to automatically reload raster layers if source is changed in QGIS?

How to  automatically reloaded raster layer if source is changed? (The path is the same but inside source file are changes)  I use:   qgis.utils.iface.mapCanvas().refresh()   but layer not refresh.  # # #  The maps are repainting but there are still the same image (source file is changed on disc)  I use:    layers = qgis.utils.iface.legendInterface().layers()   for layer in layers:       layer.triggerRepaint()


ralink 148f:760b mt7601 driver not working

I got new ralink mini WIFI dongle.  lsusb returns:  Bus 002 Device 003: ID 148f:760b Ralink Technology, Corp.   it's based on MT7601UM chip.  driver installed following : does not work.  Any suggestions apart from buying older dongle?  I've tried it on 10.04(linuxcnc) and 14.04 x64  some diags:  dmesg | grep -e mt7      mt7601Usta: module verification failed: signature and/or  required key missing - tainting kernel   modprobe returns nothing  lsmod | grep mt76 mt7601Usta            807204  0


Transform not working - right click acts like grab: what am I missing?

I'm newish to Blender, following a Udemy course. Everything has been working fine, but now suddenly when I'm in edit mode and select a vertice / edge / face, the right click just drags the entire object around instead of transforming the object by moving the vertice / edge / face.  I don't mean that proportional editing is turned on (it was suggested that this has been answered elsewhere). This is not the same question. The entire object moves - with no changes or transforming actions. Dragging any vertice of face behaves like grab: the entire object moves.  Does anyone know why this might be happening?  Have I accidentally messed up a setting somewhere?   I added another mesh in the same file and I have the same problem. I opened a new file and created a mesh there and it works fine, so it's not my input device - I've obviously done something in this file that I don't understand. If anyone has any siggestions to help me troubleshoot this, I would appreciate it. And apologies if I'm missing something that should be obvious. Thanks! Georgie  As requested, this is the viewport:    You can see the vertex selected. Clicking on this to transform it just grabs the whole object. I'm not pressing G to grab.


When and how did we start getting "off the dime"?

In American English, for a long time we've had the idiom "to stop on a dime." It means to stop abruptly and completely. It came to be used as a description for something agile or nimble. Etymonline says  Phrase stop on a dime attested by 1954 (a dime being the physically smallest unit of U.S. currency).  But for the past several decades I've heard the expression get off the dime being used to mean "get started" or "get going" and is used in the same circumstances as the idiom "get a move on." It seems obvious to me that this must be a transposition of "stop on a dime" (a metaphorical one, at least). [N.B.: This supposition is no longer obvious and appears to be nothing more than my own folk etymology, given that all the answers point to a different derivation.] I'm curious if anyone can show a link between "stop on a dime" and "get off the dime," or if there is some other explanation that might turn my bit of intuition into folk etymology.


iPhone 6s with iOS 12.4 not connecting to MacBook Pro mid2015 with macOS 10.14.6

I am using an iPhone 6s with iOS 12.4 and a MacBook Pro mid2015 with macOS 10.14.6. Since recently (I am not exactly sure when it started), I cannot charge the phone with my computer anymore. As soon as I plug the phone in, it will play the charging sound repeatedly. The right-hand side port sometimes works, the lefthand side port never works. When I connect my old iPhone 5 (using the same cable), it charges without any issues. My iPad mini 4 shows the same issue.  Sometimes the "Do you trust this computer" setting flashes on the phone and disappears before I can click anything.   How can I fix this?  Update 1  Sometimes I get the Software Update dialogue in macOS. After approx. 2 minutes it shows the following:     Update 2  For some reason the issue disappeared for a while but is back now. Disabling "Settings" > "Touch ID & Passcode" > "USB Accessoires" seems like it makes the problem a bit less bad, but not go away.  Update 3  This is driving me crazy. I upgraded to Mojave 10.14.3 mostly to get rid of the issue. It persists. Some more random information: Before logging in (Filevault pre-boot authentication), the phone will charge fine. Only when a user account is loaded, the issue appears. The likelihood of a successful connection increases with the battery state of the iPhone. Workaround 2 in my answer below suggest that this a "Trust issue" from the iPhone's side. I suppose the solution will have to be hidden somewhere there...    What I tried so far (will update):   Reset Privacy settings on iPhone Different (original, almost new Apple) lightning cables   Remove and add "iPhone USB" in Network Settings  SMC reset (), PRAM reset Upgrade to latest iOS 12.4 and MacOS 10.14.6


Hello I am Indian Citizen currently studying in Australia and I am on a student visa. In the month of November 2019 I am travelling to India for vacations and I booked a ticket from Melbourne to Bangkok and than form Bangkok to India with a layover time of 7 hours in Bangkok and I am not going to leave the airport but my flights are different, so do I need to get and Airport Transit Visa in Bangkok.


What is the justification for a Chi Squared test to assume Chi Squared distribution?

just started learning about Pearson's Chi Squared test, and found some parts to be confusing:  In the Chi Squared test, I don't understand why we can just assume the sum of the difference between observed and expected values to follow a Chi Squared distribution. Can it be another distribution? If so, how can one tell?  On a related note, the Chi Squared test does not care what distribution the observed or expected random variables actually follow. Is there some intuition how why Chi Square would work "globally" for observed and expected r.v.'s with any distribution?


Wrong vertical spacing in block title in beamer

I've adapted the example from :  \documentclass{beamer}  \setbeamercolor{block title}{bg=red!30,fg=black}  \begin{document}  \begin{frame} \begin{block}{This title has a problem}     some text \end{block} \begin{block}{This title is about fine}     some text \end{block} \end{frame}  \end{document}   The result looks like this:    The second title looks fine, but the first one looks wrong - due to the "p" crossing the baseline. How can I fix that?


I'm trying to install a theme and another forum said to create a folder in my home directory and put the theme in there, then use Unity Tweak Tool to activate it. So, I created a folder in my home directory, called it .theme. However, when I returned to my home directory, my .theme directory was gone. So I thought: I'll just make a new folder. But when I tried to create a new folder called .theme, I get an error saying that the name is already in use and I cannot use .theme. But there is no folder in my home directory titled .theme.  I'm using Ubuntu Desktop 16.04.


Rounding down to its nearest decimal? BigDecimal vs Alternate Form

I have the following formula and code:  I tried with Math.Floor, and others but I am not getting the result expected  double netPay = grossPay - totalDeduction;  System.out.printf("Net Pay: $%.2f", (netPay));   The idea is to get the number as follows:  46.225  Rounded as 46.22  and not as 46.23


package 'unrar-free' has no installation candidate xubuntu 20.03 (ubuntu based os)

hi everbody i've surfed the net alot but i could'nt get my answer,i've checked all the forums but no good result,please help me out with  this error i can't install any package even net-tools,please don't say have you done apt update,because i will do every single time . . . error : >>>>>>>> Reading package lists... Done Building dependency tree Reading state information... Done Package rar is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'rar' has no installation candidate


public partial class MainForm : Form {     public MainForm(string Username)     {         InitializeComponent();     }   Hey I tried to pass data from form1 to Mainform and all the time that show me this error     There is no argument given that corresponds to the required formal   parameter 'Username' of 'MainForm.MainForm(string)'


Is there a 'friendly' way to create dot-density maps, where a polygon attribute data defines the number of dots (e.g. 1 dot = 100 ) using QGIS 1.7+? I say friendly because after a couple of hours researching all the alternatives seem to require programming. Maybe I am not looking in the right place. I am already aware of the fTools 'Random Points' feature and it is not what I am looking for.      That is precisely what I am seeking. However every time I attempted to run this function. I received the following:   An error has occured while executing Python code:  Traceback (most recent call last): File "/usr/share/qgis/python/plugins/fTools/tools/doRandPoints.py", line 118, in accept self.randomize(inLayer, outPath, minimum, design, value) File "/usr/share/qgis/python/plugins/fTools/tools/doRandPoints.py", line 210, in randomize else: points = self.loopThruPolygons(inLayer, value, design) File "/usr/share/qgis/python/plugins/fTools/tools/doRandPoints.py", line 256, in loopThruPolygons sExt = sGeom.boundingBox() AttributeError: 'NoneType' object has no attribute 'boundingBox'  Python version: 2.7.1+ (r271:86832, Apr 11 2011, 18:37:12)  [GCC 4.5.2]   QGIS version: 1.8.0-Trunk Trunk, exported


Not able to change ssh port on Ubuntu 18.04.1 LTS

I am trying to change ssh port from 22 to 1111. I have taken following steps, but not able to.   sudo nano /etc/ssh/ssh_config Removed # where it says Port 22 Changed Port 22 to Port 1111 Ctrl + W -> Y -> Ctrl + O -> Enter -> Ctrl + X sudo ufw allow 1111 sudo systemctl restart ssh sudo systemctl status ssh   Output:   Server listening on 0.0.0.0 port 22 Server listening on :: port 22.


Insert A3 page with figure into A4 document with active references

Based on the first answer from a previous post , I tried to get a figure on an A3 page in my thesis. However, it does not turn out as it should: the picture does not get centered on the page. Otherwise it works. (see below for example output).  What I would like: The picture centered on the page and the caption on the inner half of the A3 page, just as if it were an A4 page. Any ideas? I also do need hyperref working ...   \usepackage[demo]{graphicx} \usepackage{lipsum}  \usepackage{afterpage} \usepackage{changepage} \newenvironment{hugepage}%  {\clearpage   \pagestyle{empty}  % turn off display of page numbers, headers, ...     \changepage{247mm}{370mm}{25mm}{15mm}{}{}{}{}{}} % switch to A3  {\clearpage   \changepage{160mm}{247mm}{25mm}{25mm}{}{}{}{}{}} % back to A4  \begin{document}  \afterpage{%  \pdfpagewidth=2\pdfpagewidth  \pagestyle{empty}  \begin{hugepage}    $\,$   \begin{figure}[!t]      \includegraphics[width=308mm,height=229mm,page=1]{figures/aaa.pdf}     \caption{Left side image A3.}   \end{figure}  \end{hugepage} }  \newpage  \afterpage{%  \pdfpagewidth=2\pdfpagewidth  \pagestyle{empty}  \begin{hugepage}    $\,$   \begin{figure}[!t]      \includegraphics[width=308mm,height=229mm,page=2]{figures/aaa.pdf}     \caption{Right side image A3.}   \end{figure}  \end{hugepage} }  \lipsum{3} \end{document}   Page 2 (the A3 page) looks like this:   The problem is, that the picture is not center aligned. The caption is on the right side of the odd and the even page, but it should be on the right side of the even and on the left side of the odd page.  Other suggested solutions are:   (Not an option since it requires memoir class).   (Which results in non-centered image as well. And the caption got centered as well, but it should not be). Code of which looks like this:  \afterpage{% Insert after the current page \clearpage \KOMAoptions{paper=A3,paper=landscape,pagesize} \recalctypearea \begin{figure}[p] \centering    \includegraphics[width=308mm,height=229mm,keepaspectratio]{largeimage}%    \caption{A large image which required A3} \end{figure} \clearpage \KOMAoptions{paper=A4,pagesize} \recalctypearea }   However, it messes up with the page numbers. (see page 3).


Why do echo $$, echo $(echo $$) and (echo $$) reveal the same PID?

As far as I know  echo $$   shows the PID of the current BASH I am in.  I do not know if the expasnsion $(...command...) runs the command in a subshell or the current shell, however  echo $(echo $$)   shows the same PID But, as for (...command...) I was very sure, that the command is run inside a subshell and therefore in a shell with another PID than the current shell, but  (echo $$)   shows also the same PID  So, in all three cases the same PID,namely 1771, was displayed. I am confused, based on what I learned so far, I would not have expected it. Why?


Show that the only matrices that commute with all other matrices in $GL_{n}(\mathbb{R})$ will be multiples of the identity matrix. Or:  $Z(GL_{n}(\mathbb{R}))=\{\lambda I_{n}:\lambda \in \mathbb{R}\}$    One direction is clearly obvious. However, to show that every element $g$ such that $gh = hg$ for $h \in GL_{n}(\mathbb{R})$ has to be a multiple of the identity is causing me trouble as I don't know where to begin with. What would be a way to handle this problem? I was thinking of using contradiction, but that doesn't take me anywhere.  Thanks for the help.


Why and how can you hear explosions in space in Star Wars?

Considering that sound can't travel through vacuum.


Please forgive me if this is a stupid question as I have a very rudimentary understanding of physics.  I was reading about how the large hadron collider speeds up subatomic particles to near lightspeed and that the experimenters need to take the effects of time dilation into account because of this. This got me thinking and I came up with a strange thought experiment. Instead of subatomic particles, imagine we could send something like a small vehicle with a few people in it around the "track" (track seems like an inappropriate word but I'm not sure what it's actually called) at near light speed. So imagine they also have a high def webcam with them in the vehicle and that they wirelessly send a video to be broadcast on the internet. What would we see if we were to watch this video? Would they appear to us as if they were in super slow motion?


Is a dense subspace of a separable topological space also separable?

Question is said in title.Suppose X is a  separable topological space and S is a dense subspace of X,to prove S is separable or give a counter-example,and we may add what conditions to make this statement true?


It's suggested that he work hard. It's suggested that he works hard

It's suggested that he work hard.lt's suggested that he works hard.  Which one is correct?  I think,  It is suggested that he works hard. This is correct one.  But,  how ? I am confused.  Please clear them.


What exactly happened to Ariana when Dumbledore and Grindelwald fought?

I have seen few narrations and some fan made videos on the battle between Dumbledore and Grindelwald. There was some magic that killed Ariana when both Dumbledore and Grindelwald were duelling. What may have killed her? Does the magic bounce off?


Why is != not working? how to compare with null values?

I am having a hard time understanding why the following query is not working?  select id,sold_dealer_id from myi_corporate where sold_dealer_id != 36;  When I do the following I am getting the result  select id,sold_dealer_id from myi_corporate where sold_dealer_id = 36;  However for != I am not getting the opposite results.   I am returning to psql after a long time after using MongoDB and might have forgotten the basics. Any suggestion is much appreciated


When to start watching HBO's Game of Thrones when reading the books?

I've started reading George R. R. Martin's "A Song of Ice and Fire" book series, and I intend to watch HBO's television series based on it at some point. I wonder about two things:   Should I start watching the series before having finished all the books?  If so, which chapters should I have read? What is a good starting point?   The point is obviously avoiding spoilers.


Finding the remainder of $823^{823}$ in the division by 11

I wish to find the remainder $823^{823}$ in the division by $11$.  I used the  Euler-Fermat theorem  that tells that: $a^{\phi(n)} \equiv 1$ $(\mod n)$, whenever $(a,n) =1$ First, Euler- Fermat tells us that $a^{\phi(11)} \equiv 1 (\mod 11)$ whenever $a$ is coprime with to 11. Since 823 is prime, we have, $(823,11) = 1$. Now $823 \equiv 9 (\mod 11)$  But I don't know how to continue.. Because both $823$ and $11$ are prime ; do I have to use Fermat's little theorem?   Any help appreciated


How can I remove the site URL from enqueued scripts and styles?

I'm dealing with an SSL issue and I would like to strip the domain from all scripts and styles being output via wp_enqueue_scripts. This would result in all scripts and styles being displayed with a relative path from the domain root.  I imagine there is a hook that I can use to fileter this, however, I am not sure which one, nor how to go about it.


Good abstract algebra books for self study

Last semester I picked up an algebra course at my university, which unfortunately was scheduled during my exams of my major (I'm a computer science major). So I had to self study the material, however, the self written syllabus was not self study friendly (good syllabus overall though).  The course was split up into 3 parts, group theory, ring theory and field theory. As a computer science major we only had to study the first 2.  Now that I passed the exam for this course I want to study the field theory part ( which covers Galois theory, etc).  So, now I want to ask whether any of you know any good books on abstract algebra, which lift off at basic ring theory and continue to more advanced ring theory and to finite fields, Galois theory, ...  Please keep in mind that I am not a math major, and that I would like books which are suited for self study (thus a lot of examples and intuition).  Thanks in advance!


Applying ownership patterns from another server

Let's say that there are two dedicated servers, freshly installed, with identical software and users on both of them.  Suppose that, for whatever reason, I would like to copy ownership patterns from one of these servers to another. Is that possible?


Why does dark matter form a halo, Unlike normal matter?

Hi I am curious to know why dark matter forms a halo? Or why doesn't normal matter form a halo.What is the difference between the two  My level is amateur


Why does the wrong image appear after I motion track it?

I made a blender scene, motion tracked an image, animated my bull model, then rendered and the image showed up. Then I wanted the bull in another image, so I went to the movie clip editor and added an additional image. I motion tracked, and even the camera perspective shows it. The problem is, when I render the first image shows up instead of the new one I added. I tried clicking the x on the first clip but that didn't work. The first picture shows the camera perspective with the image I want and the second image shows the image that it renders on, with the trackers from the previous render!


I am having dependency problems, whenever I do an apt-get install, I get this error message:    I already tried:   apt-get clean, update, upgrade, install -f dpkg --configure -a   What should I do now?


Can voltage across an inductor change instantly?

If current is passed through an inductor, there will be a voltage across it. If that current source is disconnected, the voltage across it reverses. Does this happen instantly?


Given a filepath, I would like to find out how many lines there are and store them into a variable. For example:  /three_little_pigs.csv  straw wood bricks   In a file, I would like to have the number (or string 3) stored. Tried the following commands:  export P="three_little_pigs.csv" NUM_LINES=(wc -l < "${P}")   but I'm always getting this error:  bash: house: line 12: syntax error near unexpected token `<'


In  my textbook I met an expression explaining the difference between modals must,have to,can etc. But my question is about stylistic with the usage of word only.   You can only smoke here.  Is there any difference  in meaning if I say:  You can smoke only here  Does it change my sentence or may be  its  not correct at all?


If I am correct in stating that a factorial of a number ( of entities ) is the number of ways in which those entities can be arranged, then my question is as simple as asking - how do you conceive the idea of arranging nothing ?   Its easy to conceive of a null element in the context of arrays, for example - so you say that there is only one way to present a null element.   But, in layman terms - if there are three humans $h1, h2, h3$ that need to be arranged to sit on three chairs $c1, c2, c3$ - then how do you conceive of a) a null human, and b) to arrange those ( that ? ) null humans ( human ? ) on the three chairs ?   Please note that referral to humans is just for easy explanation - not trying to be pseudo-philosophical. Three balls to be arranged on three corners of a triangle works just fine. So basically, how do you conceive of an object that doesn't exist, and then conceive of arranging that object ?  So, in essence ... is $0! = 1$, a convenience for mathematicians ? Not that its the only convenience, but just asking. Of course, there are many.  If yes, then its a pity that I can't find it stated like so anywhere.  If not, then can anybody suggest resources to read actual, good proofs ?


What does "notice me senpai" mean, when a boy says it to you?

So this boy in my class said to me, "notice me senpai".  What does it mean?     I think they like me, so does that have anything to do with it?


How do I Create a Workspace in Ubuntu 18.10 Minimal Install?

I'm trying to create another workspace in my Ubuntu 18.10 minimal install machine and I cannot figure out how to create a new workspace.  Most websites say to hover your mouse on the right side of the activities screen, however this does not do anything:    Do I need to install a workspace package or enable workspaces in settings?  How do I use a workspace from the basic 18.10 install?  Edit: As it turns out, this is the Applications screen.  Somehow, on the new install of 18.10, the Windows key + tab no longer opens the Activities screen (I believe in 16 it did) and instead mimics the alt + tab shortcut to switch windows.  The new way to open activities is to press the Windows key.


Different ways to produce a confidence interval for odds ratio from logistic regression

I am studying how to construct a 95% confidence interval for odds ratio from the coefficients obtained in the logistic regression. So, considering the logistic regression model,  $$ \log\left(\frac{p}{1 - p}\right) = \alpha + \beta x  \newcommand{\var}{\rm Var} \newcommand{\se}{\rm SE} $$  such that $x = 0$ for control group and $x = 1$ for case group.  I have already read that the simplest way is to construct a 95% CI for $\beta$ then we applied the exponential function, that is,  $$ \hat{\beta} \pm 1.96\times \se(\hat{\beta}) \rightarrow \exp\{\hat{\beta} \pm 1.96\times \se(\hat{\beta})\} $$  My questions are:     What is the theoretical reason that justifies this procedure? I know $\mbox{odds ratio} = \exp\{\beta\}$ and maximum likelihood estimators are invariant. However, I do not know the connection among these elements. Should the delta method produce the same 95% confidence interval as the previous procedure?  Using the delta method,  $$\exp\{\hat{\beta}\} \dot{\sim} N(\beta,\ \exp\{\beta\}^2 \var(\hat{\beta}))$$  Then,   $$\exp\{\hat{\beta}\} \pm 1.96\times \sqrt{\exp\{\beta\}^2 \var(\hat{\beta})}$$  If not, which is the best procedure?


Only show launcher on specific workspace?

Is it possible to only show the launcher on a specific workspace? I would like the launcher for my top left workspace, but none of the others.  I seem to remember seeing an option or setting for this, but now I can't find it now that I need it.


What were FN-2187's specific duties in sanitation?

What is sanitation? What does he do? I'm not look for the why. Does it have something to do with garbage? The garbage compactor?


Asus RT-N66U Port Forwarding with VPN to PIA

I have an Asus RT-N66U router (using the latest firmware) that is connected to my ISPs fiber modem using PPPoE.  I have signed up for VPN access to PIA and setup the router to connect using its VPN client.  I also have a number of ports that I've opened for various applications in my network.  Now, both of these are working correctly - when used separately.  When I activate the VPN client all of the port forwarding stops working both through my normal IP address and through my VPN endpoint IP address.  Even with the VPN connection up, should I not be able to still make connections to my regular local IP address?  EDIT: For everyone pointing me to "Access my home network printer while I am using VPN to connect to work" - this is not the same as my question.  In that question, the user could not connect to his printer INSIDE his network while having an active VPN link.  My issue is having connections from the Internet INTO my network while the VPN link is up.  For example, if I have my VPN link connected to PIA, I cannot access my cameras from my work computer because my router just rejects the connection on port 9000.


How to take only the integer items and calculate sum from the list?

Here i have list with product name and product price but i want to take only the products price from the list and calculate the total price of all products. How can i do it ?  For example i have a list: all_products = ['food',1000,'pasta',500,'beer',400] how can i do : 1000+500+400 = 1900


lualatex breaks after update to texlive 2016

After I install the texlive 2016 (schema full), I got the error:  ! Missing number, treated as zero.   by compiling the code below with lualatex::  \documentclass[]{scrbook}  \title{Test}  \begin{document} \maketitle test \end{document}   There is no problem with pdflatex.  Hast my file an error, or must I search the error elsewhere?


Prove that $\gcd(a, b) = \gcd(a, b + ma)$?

How can I prove that $\gcd(a, b) = \gcd (a, b + ma)$?  I have tried this:  let $g = \gcd(a, b)$, then $g \mid a$ and $g \mid b$. This means that $g \mid ax+by$.  I don't know what to do next.  Thanks.


So, I created a cylinder and extruded one of its ends a couple of times in one direction (right in image 1). Works fine. But when I extrude the other end in the other direction, the faces become "corrupt" (see the part to the left in image 1). I see no logic in this, and since I am following a very basic tutorial, I understand that this is not expected behaviour. Note in image 2 that the problem part is kind of darker in wireframe shading.  Can someone give me a clue? Many thanks.


How can I get bootstrap row to fill 100%?

I'm trying to make the red "content" part fill "the rest of the screen". Making room for the menu on top, and options on the bottom. How can i make content fill out, so there is no more white space? I've tried setting it and the parent objects height 100%, but then i squeezes out so it enables the vertical scroll bar to see the options.      html, body {     height: 100%;     margin: 0px; }  .container {     background-color: pink; }  .col {     border: 1px solid black;     background-color: teal; }  .content {     background-color: red;     text-align: center;     display: block;     width: 100%;     height: 100%; }


Error: undefined control sequence in .\maketitle

I am posting the Latex main file MWE herewith. While trying to compile file, getting an error as described below in line--.\maketitle. Can anyone please help me resolve it? Working on texmaker + texlive.  \documentclass{SVNITPhDrpsPB} %\documentclass[newchapterodd]{SVNITPhDrpsPB} % Uncomment to start every new chapter on odd page. Do not forget to comment previous line 20.  % Necessary packages (Do not comment these) \usepackage{fancyhdr} \usepackage{longtable} \usepackage{array} \usepackage{graphicx}  %Preamble  %Do not omit the following fields \rpsNumber{} %RPS number \thesisType{Credit Seminar} %Type (Ex. Thesis) \atitle{Mr.} %Author title. Valid entries : Mr. Ms. Mrs. \author{Saurabh Kumar Pandey} %Author name \title{Collaborative Data Processing in Wireless Sensor Networks} %Report title \dept{Computer Engineering} %Department name \regno{DS14CO006} %Registration number  \semester{Odd} %Even or odd \stitleI{Dr.} %Supervisor title. Examples : Dr., Prof. \supervisorI{xxx} %Supervisor name \supervisorA{xxx} %Supervisor's affiliation / Institution \addressInstN{xxx} %Institute name line1 \addressInstI{xxx} %Institute name's initials \addressInstD{xxx} %Institute name line2 \addressInstP{xxx} %Institute name line3 (Place) \acMonth{May} %Month \acYear{2014 -- 2015} %Academic Year \calYear{2015} %Calander Year \instlogo{./fig/SVNITlogo.pdf} %Institute logo file path  % User packages (You can add as many as you want) \usepackage{amssymb}  %  for double struck characters \usepackage{subfigure} % for subfigures  \usepackage{amsmath}  % User commands \newcolumntype{L}[1]{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}m{#1}} \newcolumntype{C}[1]{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}m{#1}} \newcolumntype{R}[1]{>{\raggedleft\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}  \newcommand{\BigO}[1]{\ensuremath{\operatorname{O}\bigl(#1\bigr)}}   %\usepackage{enumitem} \begin{document}  \addpageborder  %%Create the title page \maketitle  \pagenumbering{roman} \setcounter{page}{2}  %Create the Table1 (Admin) page \putTableAdmin{\input{./Tables/tableAdminData}}  %Create the Table2 (Technical) page \putTableTech{\input{./Tables/tableTechData}}  % Create the decleration page \putdecleration  % Create the approval page \putapproval  % Create the acknowledgement page \putsvnitack{ \input{./Chapters/Ack} }  % List of publications %\input{./Chapters/Publication}  % Create the abstract page \putsvnitabstract{ \input{./Chapters/Abstract} }  % Table of contents \tableofcontents\newpage  % List of figures \addcontentsline{toc}{section}{List of Figures} % Entery in ToC \listoffigures\newpage  % List of tables \addcontentsline{toc}{section}{List of Tables} % Entry in ToC \listoftables\newpage  \clearpageborder  % To change page number and style at any time, use the following %\pagenumbering{roman} %\setcounter{page}{13} \pagenumbering{arabic} \setcounter{page}{1}  % Your RPS chapters  %%Chapter 1 \input{./Chapters/Introduction} \input{./Chapters/Review} \input{./Chapters/QoS} \input{./Chapters/Routing} \input{./Chapters/Summary}  % Bibliography \bibliographystyle{IEEEtran} \bibliography{Literature} \nocite{*}   \end{document}   Error:  ! Undefined control sequence. <recently read> \c@lor@to@ps l.72 \maketitle The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined.


Software to synchronize two directories (local/remote)

I need software that would detect changes in directory (A) every 5 seconds or so and upload/delete changed files from/at (B) remote directory.  I found non-commercial software, . I am wondering if there are any commercial alternatives?


While researching the cause of refraction, I found that refraction occurs due to the change of speed of light when it goes from one medium to another (according to Huygens principle).  But I cannot get why actually does its speed change when the medium changes?


Can I count a 2015 expense, if I paid the bill in 2016?

I incurred an expense in 2015, put it on a credit card, but didn't pay it off until January 2016, can I count that as an expense for 2015?


Why are reputation requirements different depending on the site?

I've noticed something on multiple different stack sites that confuses me. For some reason, the reputation requirements for certain privileges are different.  For example, you need 50 reputation be able to comment on Stack Overflow questions, but you only need 5 on Meta Stack Exchange.  Another example, you need 1500 reputation on Stack Overflow, 500 on Meta Stack Exchange, and 1000 on Math Stack Exchange for the same privilege; create tags.  Why is that?


Making master pdf editor default for .pdf files

I have followed the answer posted by Moderator Mitch user 59676 and created mpe.desktop file, right clicked on the file and 'open with other application' - 'show other applications' did not list master PDF editor so unable to make as default.


What is the Visual Studio C# Compiler Doing in a Foreach Loop

When stepping through C# code, I notice that the debugger stops three times in a foreach declaration:   First, it highlights the collection. Then, it highlights the in operator. Last it highlights the variable.   I'd like to understand what the debugger is doing. For example, it makes sense in a for loop. During initialization, it assigns the variable, then checks the condition. At the beginning of each subsequent loop, it updates the variable, then checks the condition.  It seems in a foreach, it would need to get an enumerator at the in operator during initialization, then only assign the next item at the beginning of each loop.  I'm using Visual Studio.


On Stack Exchange sub-sites it seems to be a common practice to refer to other Stack Exchange sites by abbreviating the ".stackexchange.com" part of the domain to simply ".se" (often capitalized), as in "math.SE" or "unix.SE". These aren't actual Stack Exchange domains, but they could be, answering only to GET on the root path and redirecting to the relevant .stackexchange.com URL.  Pros:   Leverages an existing community custom from an abbreviation convention to actual references to the relevant sites. Shortens getting to the main page of a site by 15 characters.   Cons:   Some domains such as unix.se are already in use, which at the very least complicates things. Introduces an inconsistency if .se domains for some important sites cannot be bought.


I downloaded ubuntu-15.10-desktop-amd64. I have never programmed before and I am trying to learn linux. somewhere I saw that I can learn linux on ubuntu (to be honest I don't get that even). anyways after installing I can't seem to open the program.. after I open what i installed, it asks where I want to copy the program or something? please help. thanks


A person who knows how to read but cannot write

What do you call somebody who can read but cannot write?  I found the term semiliterate, the  says        Having achieved an elementary level of ability in reading and writing.      But  defines it as      semi-literate: Unable to read or write with ease or fluency; poorly educated:   I want a word that means a person who only knows how to read. Is there such a word?


Using an instance of an object as a key in hashmap, and then access it with exactly new object?

I have a hasmap with a key object,   HashMap<Key, Object> test;   and make new Key("the same") as key..  so its like..:  test.put(new Key("the same"), someObject);   (without storing that key in a variable)  so.. after a while... i want to access the hashmap, because i do not have the object, i've tried to make new Key("the same") and make it as a key. But it didnt work.  How to make it work? (without saving the first object "key" in a variable)  So meanwhile, for now, im using String object as a key.  HashMap<String, Object>


British Airways from Charles de Gaulle to Bangalore

I am traveling from Paris to Bangalore via London Heathrow on British Airways as I don't have to change the terminal at LHR   Kindly advise if I will need a transit visa, as my onward is booked to US from bangalore


Can we create a chaotic integer-valued system?

Can we create a system of recurrences that exhibits chaotic behavior, with the restriction that we are only allowed to use the integers?  For example, we could create a system:  $$ \begin{align} a(t) &= a(t-1)^2 +b(t-2) + 3c(t-1)  \\ b(t) &= 3 + a(t-1)  \\ c(t) &= b(t-1)b(t-2)^2 \\ & \vdots \end{align} $$  I'm of course looking for a system that stays within some boundaries for certain intial conditions.  In other words, maybe:  $$ \begin{align} -20 \le a(t) \le 100  \\ 15 \le b(t) \le 50  \\ -100 \le c(t) \le 100 \\ & \vdots \end{align} $$  Of course, all of the functions I mentioned are just examples.  The main problem is that the functions must exhibit what I will call "totally integer functions".  That is to say that they must be functions from integers to integers.  That disallows division, since we could get a non-integer result.  It also disallows floors, ceilings, and modulo functions, for example.  I also cannot use function composition, unless the total depth of recursion is less than $\log{(\log{(n)})}$ for a function with all values between $-n$ and $n$.


One sensor output gives voltage range within 5mv to 50v..I need to give this to an adc (analog to digital converter )..however the adc available is upto 10v.i need to stepdown hight voltage to low voltage(50v to 10V, 25V to 5V like this linear) to give it within adc input range..Any standard circuitry for this to reduce this high voltage dc?


How write a symbol of the circle in the Latex?


Add an existing node as a translation to another node

I am migrating contents from a multilingual website. I'm using Feed modules to import all the nodes so, in the end, I have multiple nodes that are in English and multiple nodes that are in French. Then, i wrote a DRUSH command where I have a CSV file that contains URL Alias of both slug of English and French. I can then process that info and get the node ID of both related Node.  But I just can't see how I can't tell drupal to attach an existing node (FR) as a translation of another node (EN). Does anyone has ever wanted to do something similar?  Thanks!


Is there a single word that means "self flagellation" or "self punishment"?

In the back of my mind, I'm almost certain there are at least several individual English word that means to punish one's self. It doesn't have to be physical, necessarily, but it must be some kind of self-punishment. Are there such words? Clinical words are also accepted (i.e. psychological terminology).


We're using an AWS ELB to do SSL termination and are having an issue where Chrome is displaying "https" in red with a strikethrough.  It says "The site is using outdated security settings that may prevent future versions of Chrome from being able to safely access it." but it doesn't explicitly call out what setting it doesn't like.  How can I find out what Chrome is having a problem with so that our users will get a green checkmark?  An example URL producing the error is here:     I ran our site through SSL Labs and it gave us an "A" Grade:


If I reference a medical textbook or website for hand drawing bones is that considered copyright infringement?

I can't quite figure this one out. I am not copying a custom piece of work, I am copying something that is available in nature, bones. I am also not tracing it, I am drawing by hand using them as a reference for accuracy. So, is that considered copyright infringement? Does it depend on how similar my drawings are to the ones I visually copied?  So if I look at a medical website or book and see a knee bone, then I draw one on paper or in a graphics editing tool by looking, with my eyes, at the referenced image, is that going to get me in trouble somehow?  I mean, surely I don't have to go find my own skeleton to draw from... right??


Is there a difference in meaning between "criticism of the police" and "THE criticism of the police"

A of B consideration of B use of B destruction of B B is an object of A but in some cases, B becomes a subject: the arrival of the police (the police arrives) So I am asking about what the difference is between: criticism of the police (=sb criticizes the police?) and the criticism of the police (=police criticizes sth?)


Let $X$ a vector space on $\mathbb{R}$ and denote with $\theta$ the zero vector, i must prove that $$0x=\theta$$ for all $x\in X$  Now,  $0x=(0+0)x=0x+0x\Rightarrow$ $0x=\theta$  Correct?


How to disable middle mouse button paste in KDE?

I want to disable middle mouse button paste, but still be able to:   Close tabs by clicking it with the scrollwheel Open links in a new tab by clicking the link with the scrollwheel.   I tried , but that makes closing tabs and clicking links unusable.  This question is not a duplicate because in the other question they want to disable the middle mouse button completely.


How to prevent SQL Injection on PDO::exec

I guess the easiest way to prevent sql injection on PDO::Query which take arguments from the user is to use PDO::prepare and PDO::execute. However in my case I have an insert statement which takes a param from user. For this purpose I'm using PDO::exec. Below is not the exact code.  $db = new PDO("Connection String to connect to MSSQL"); $rowsAffected = $db->exec("Insert into MyTable (UserParam) Values($userParam)");   How can I prevent an sql injection on this?


Flag raised was rejected. How to re-flag the post?

So, I am trying to be a vigilant member of Stack Overflow.   I flagged a few posts, and noticed that some of them were rejected/disputed.   Of course, my little ego was bruised (just joking) and I went back to check the flagged posts.   I still stand by my flags, but I apparently can't re-flag them.   Is there a way I can get a moderator's attention in that scenario?   Here are some examples :    In this case, the OP himself says that the answer is not related to his question. Yet, my flag (not an answer) was declined.     These flags were mainly raised when I was reviewing 'Late Answers'. So, from what I understood, you just don't down-vote irrelevant posts, you flag them too (if necessary), when doing the reviews?


anyone knows how to disable Edit Source function? I am developing my project using the blender, I would like to disable Edit Source option whenever user Right Click on the UI, there is an option the user can choose to see the source code. I would like to disable it, how can I do it. I want to prevent the user from Right click and choose to go to the edit source.   Thanks


What is the name of the small containers of half & half, etc.?

Does anyone know what the word/name for the small plastic cup things that contain liquids (like half and half for coffee) is?  Right now I’m using sachet because a coworker started to do so, but I’ve never heard them being called that (looked it up and apparently it's legit).  I’ve thought of packets but I feel like there might be a proper word for it. Also, what do people call it in everyday usage? I don’t drink coffee so I’ve never really had to think about it.


Let $p$ and $q$ be the positive integers such that $1 - \frac{1}{2} + \frac{1}{3} - ... - \frac{1}{54} + \frac{1}{55} = \frac{p}{q}$ . Prove that $83$ divides $p$ .  What I Tried :- To me it does not actually seem like an easy problem for me. (I guess I couldn't figure out the idea) This expression I found is same as $$\displaystyle\sum_{n=1}^{55} \frac{(-1)^{n+1}}{n}$$ And calculating this in Wolfram Alpha gives the answer to be this in the simplest form :- $$\displaystyle\sum_{n=1}^{55} \frac{(-1)^{n+1}}{n}=\frac{115328583812490186710549}{164249358725037825439200}$$ Surprisingly, I found that $83$ really divides the numerator of the fraction. Now I got puzzled, how will you show this without using Wolfram Alpha or a Calculator? Can Anyone Help?


"Root file system not defined. Please correct this from partitioning menu" Ubuntu 14.04 installation problem in pre-installed win 8 laptop

I am not exactly new to Linux, but I am facing problems trying to install Ubuntu 14.04 LTS on my Dell Inspiron 14z pre-installed Windows 8 with Secure Boot nand UEFI mode. **I have followed all the prescribed steps of your post regarding Ubuntu installation one of this forum's post  **.  I am able to boot to LiveUSB mode via UEFI mode. But when going through the installation process, partitions don't appear at all on the 4th slide of the install process. So I just press "Install" just to see what happens. There is a pop-up window which says "No root file system defined. Please correct this from the partitioning menu."  I have created three partitions on Windows 8 of which one is entirely free(100 GB) and formatted and ready to be installed on. Please help me resolve this issue. Thanks and cheers


Not able to ping to IPV6 address from Windows 7

Mine is Windows 7 both on laptop(home) and PC(office). I've also tested checked this from a school on Win8 PC . Why I can't ping any IPV6 address?  I've disabled Eset nod32 completely but still:  >ping ipv6.google.com Ping request could not find host ipv6.google.com. Please check the name and try again   While nslookup(Win7) is working fine:  >nslookup ipv6.google.com Server:  google-public-dns-a.google.com Address:  8.8.8.8  Non-authoritative answer: Name:    ipv6.l.google.com Address:  2404:6800:4007:805::200e Aliases:  ipv6.google.com   **IPCONFIG ** (Win8 PC)  >ipconfig /all  Windows IP Configuration     Host Name . . . . . . . . . . . . : CID-7244    Primary Dns Suffix  . . . . . . . : removed.ac.in    Node Type . . . . . . . . . . . . : Hybrid    IP Routing Enabled. . . . . . . . : No    WINS Proxy Enabled. . . . . . . . : No    DNS Suffix Search List. . . . . . : removed.ac.in  Ethernet adapter Ethernet:     Connection-specific DNS Suffix  . : removed.ac.in    Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller    Physical Address. . . . . . . . . : 78-45-C4-26-18-C7    DHCP Enabled. . . . . . . . . . . : Yes    Autoconfiguration Enabled . . . . : Yes    IPv4 Address. . . . . . . . . . . : 10.10.1.56(Preferred)    Subnet Mask . . . . . . . . . . . : 255.255.0.0    Lease Obtained. . . . . . . . . . : Monday, August 17, 2015 8:11:07 AM    Lease Expires . . . . . . . . . . : Friday, August 21, 2015 8:10:32 AM    Default Gateway . . . . . . . . . : 10.10.0.1    DHCP Server . . . . . . . . . . . : 10.1.1.18    DNS Servers . . . . . . . . . . . : 10.1.1.16                                        10.1.1.17                                        10.1.1.19                                        10.1.1.18    NetBIOS over Tcpip. . . . . . . . : Enabled  Tunnel adapter isatap.removed.ac.in:     Media State . . . . . . . . . . . : Media disconnected    Connection-specific DNS Suffix  . : removed.ac.in    Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2    Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0    DHCP Enabled. . . . . . . . . . . : No    Autoconfiguration Enabled . . . . : Yes


Why bumble bee cannot fly aerodynamically?

I just saw this pic     So I got curious and logged in on physics.stack first time, is it true? I am a math major and usually wander on mathstack but I would like to understand why Bumble bee cannot fly according to physics laws but still do? I am only familiar with high school physics, no aerodynamics at all. If some one can explain it to me in easy terms, I'll be obliged.


NullPointerException on android 4.4.3 but not 4.1.2

I have a problem where by a section of my android app works fine on android version 4.1.2 but throws a NullPointerException when the same section is executed on android 4.4.3. My minimum sdk is set to 15 and target sdk is 21. Please find the code below:  try {     FileInputStream towe = new FileInputStream(path2);     re = new BufferedReader(new InputStreamReader(towe));     while ((res = re.readLine()) != null) {         result.append(res);     } } catch (FileNotFoundException e) {     e.printStackTrace(); } catch (IOException e) {     e.printStackTrace(); } finally {     try {         re.close();           //ERROR IS GENERATED AT THIS LINE     } catch (IOException e) {         e.printStackTrace();     } }   Morning guys, been away for a while. It turned out Exception was being thrown because of file path. I had hard-coded the path for android 4.1.2 but in 4.4.3 that path was different even though device was the same. I ended up using the   android.os.Environment.getExternalStorageDirectory();  method. Now working fine on both. Thanks for the suggestions


Unbalanced Design with a Large Data Set and Logistic Regression

I have a dataset with a binary dependent variable.  There are 40,000 observations, from which 30,000 are from group 1 and 10,000 from group 2.  I have a set of predictors.  I tried running logistic regression, but ran into troubles, with the P-Values always being significant, due to the size of the data.  I then tried looking at effect sizes to choose the variables for the final model.  Then an idea came to me, to try and classifying models to help and choose the variables.  But my data is unbalanced, and I know that it masks effects.  My question to you, is double: 1. Can I even use logistic regression with unbalanced design?  2. I know that I can't use decision trees with a very unbalanced design, as it masks the classification effect, however, I read here a bit about balancing the data, and it making the conclusion a-posteriori.  Can you please explain the meaning of this?


Unable to Install apps onto my iPad (Stuck on "waiting...")

For the past several days, I have been unable to install ANY apps onto my iPad.  When I click "GET" and then "INSTALL", it just says "Waiting..." below the app icon.    This is what it looks like (not from my iPad, from Google):    I've tried the following to attempt to resolve the issue:  (I had no other apps updating/installing)   Restarted the device Turned on and off the device Updated the iOS 8 software to latest version Went to Settings>General>Reset>Reset All Settings Restarted AppStore Synced my device with iTunes Deleted app and tried to reinstall Logged out of Appstore Logged back in to Appstore Turned off/on wifi   In addition to not being able to download apps, I can't download books from iBooks either.  I don't know if this is a software issue, or if it's a network issue.


"Why can't I see?" or "Why I can't see?"?

Which of the following is correct?     Why can't I see?   Why I can't see?   I am a bit confused, since both have inversion, negation and a "why" in the beginning.


How to Mark NTFS filesystem dirty from *NIX/Linux?

Is there any way to mark a NTFS-fileystem dirty using ntfstools/ntfs-3g or any other tool, so it gets chkdsk'd when windows boots? I know I can do that from windows or the recovery console but I'm curious if this is possible.


Why am I getting a linker error? (Function template)

I am getting LNK1120 error, and I am not sure why. I am trying to use a template for int and double, that returns the corresponding type.   This is my Numerical_Analysis_Functions.cpp file  #include "Numerical_Analysis_Functions.h" #include <iostream> using namespace std;  template double  midpointRule<double>(double arr[], int);  template <typename T> double midpointRule(double arr[], int size) {      return 1.0; }   This is my Numerical_Analysis_Functions.h file  #pragma once  template <typename T> extern T midpointRule(T arr[], int size);   This is my main  #include <iostream> #include "Numerical_Analysis_Functions.h" using namespace std;  int main() {     double arr[4] = { 1, 2, 3, 4 };     midpointRule(arr, 4);       cin.sync();     cout << "End of Program.";     cin.get();     return 0; }


How can a non resident of US open a US Bank Account?

Please is there anybody with useful hints or information on how to open a US Bank account as a foreigner in the USA?


How do I Enqueue styles/scripts on Certain /wp-admin Pages?

I have two simple functions that load stuff using  and , something like these:  function admin_custom_css() { wp_enqueue_style( 'stylesheet_name', 'stylesheet.css') };   function admin_custom_js  { wp_enqueue_script( 'javascript_file', 'script.js') };   ... and a few admin pages, created with  and   function my_menu() {    add_menu_page('Page 1', 'bar', 'something', 'else', 'foo');    add_submenu_page( 'theme_menu', 'Subpage 1', 'Subpage', 'something', 'else', 'foo');  } add_action('admin_menu', 'my_menu');    How do I load my two functions only on these pages?  Right now I'm using:  add_action('admin_init', 'admin_custom_css' );  add_action('admin_init', 'admin_custom_js' );     But it loads my files on every admin page, which is not nice at all.  Can I do this via one simple line in functions.php or have to enqueue them within my pages separately (I prefer the first option strongly, since I'd have to edit a lot of admin-page-creating-functions).  Thanks!


How do I start DMing a new game after the Red Box?

I finished playing the D&D beginners Red Box with my friends. Now how do I start DMing another game? Where do I go from here?


How to see all options configurable by "defaults write ..."

Many Mac apps have "hidden" configurable options that can be modified in Terminal by using the defaults write ... command. This is straightforward to do if you know the name of the option that you want to configure ahead of time.  Is a list of values that each application actually uses tucked away somewhere in a master config file?   How do people discover these options without a list of all configurable options for a given Application?


How to create the Case with Attachments in single Rest API call

I need to create a Case with Attachment(s) in Salesforce using Rest API. The Case Team should be assigned on created Case. Also the Case Feed Item should be created with some text where the uploaded attachments should be linked. I know how to do it using one Rest API call for each operation. So in my case it will be 6 API calls for 3 attachments. At least I would like to reduce the API calls. Also some kind of transaction required in my case. It is possible to do such operation in one API call at least for Case with Attachments? Can I use something like transaction with REST API? Currently I'm looking into this .


understanding the relation between hashcode and equals method in Java

This is my understanding about hashcode and equals method :         if obj1.hashcode == obj2.hashcode (returns true) then obj1.equals(obj2) returns true and   if  obj1.equals(obj2) returns false (returns true) then obj1.hashcode == obj2.hashcode (returns false)      is this correct?


Carbon-14 has a half-life of 5,730 years.  That means that after 5,730 years, half of that sample decays.  After another 5,730 years, a quarter of the original sample decays (and the cycle goes on and on, and one could use virtually any radioactive isotope).  Why is this so?  Logically, shouldn't it take 2,865 years for the quarter to decay, rather than 5,730?


Why is there no color in my lava material?

I followed a tutorial and it looked great there but mine has no color and also has no displacement either. tutorial i followed here:


Unable to change user name on Windows 10

I want to change the command prompt user name being displayed to bilesh instead of biles    I used the following command.  wmic useraccount where name='biles' rename name bilesh   Which was successful. Then, I restarted the machine. But the folder name was not updated.  Any way I can do this without breaking anything?


Windows 7 Laptop Sound: Mixer has green bar but no sound from speakers of headphone jack

Have a Sony Vaio laptop. Sound bar on sound mixer is green but no sound from speakers or headphones. Wondering what should I check?


Is it possible to call a specialized integer templated method?

I have a non-template class that is itself used as a template parameter of another class. This class is used to abstract the underlying representation of some data. Ideally, one of the method of this class should be integer parameterized.  E.g  :     typedef double Price;   enum Side {   BUY,   SELL };  struct Book {   template <Side side>   int getLimit(Price price) const   {     return 0;   } };  struct Spotter {   template <typename Book>   Price compute(Price startPrice, const Book& book)   {     int limit = book.getLimit<BUY>(startPrice);     return 0;   } };   Now when compiling with gcc, I get  "error: no match for 'operator<' in book->Book::getLimit < (Side)0u"  It looks like a parsing error as if the grammar does not allow object.method(args) to be written in the first place.  Note that in my real code, the compute() method is itself parameterized by a side parameter, which is forwarded to the getLimit() method.  Is there a way to make this work  ?


What is the meaning of "momentarily" in this sentence?

What is the meaning of momentarily in this sentence:     Would love to chat on the phone momentarily.    For a very short time,  briefly. Very soon.


NullPointerException in Serialized objects

I am trying to make a program that can save data as "data.ser" and retrieve it and output it. However, although it does the task, the program shows that there is an issue with the NullPointerException. public void loadData(){                  ArrayList<Object> deserialized = new ArrayList<Object>();          try {             FileInputStream fileIn = new FileInputStream("data.ser");             ObjectInputStream in = new ObjectInputStream(fileIn);             deserialized = (ArrayList<Object>)in.readObject();             in.close();             fileIn.close();         } catch(IOException i  ){             i.printStackTrace();                      } catch(ClassNotFoundException c){             c.printStackTrace();                      } catch(NullPointerException e) {             e.printStackTrace();                  }  The message that always pops up when I run the whole program is Exception in thread "main" java.lang.NullPointerException at student_Copy.Main.loadData(Main.java:94) at student_Copy.loadData.main(loadData.java:9)  There is also a class that retrieves the file public class loadData {  public static void main(String[] args) {     Main main = new Main();     main.loadData();      }


I have multiple accounts because I kept trying to start all over. Sometimes I will friend people and they say comments that are inappropriate. And I have forgotten the passwords to those accounts. How would I locate them and close them?


What is a simplified example with xmodmap to have AltGr similar to windows?  clear Mod1 keysym Alt_R = Alt_R add Mod1 = Alt_L Alt_R keycode 56 = x X x X f F   I assumed this would work but it does not.