I am having an issue using vectors with a custom class that I am creating. Here is my code  vector<image> frames;   int i = 0; while (i < n) {   image tempImage;   tempImage.read(fullname);   frames.push_back(tempImage); }   And the constructor for image is just image() {};  I am sure I am missing something simple, but I cannot figure out what it is. Here are my errors  /usr/include/c++/4.2.1/ext/new_allocator.h:107:20: error: no matching constructor for initialization of 'image'   { ::new(__p) _Tp(__val); }                ^   ~~~~~ /usr/include/c++/4.2.1/bits/stl_vector.h:604:20: note: in instantiation of member function   '__gnu_cxx::new_allocator<image>::construct' requested here         this->_M_impl.construct(this->_M_impl._M_finish, __x);                       ^ video.cpp:50:10: note: in instantiation of member function 'std::vector<image, std::allocator<image> >::push_back'   requested here             frames.push_back(tempImage);                    ^ ./image.h:25:4: note: candidate constructor not viable: 1st argument ('const image') would lose const qualifier image(image &img); ^ ./image.h:24:4: note: candidate constructor not viable: requires 0 arguments, but 1 was provided image(); ^ In file included from video.cpp:1: In file included from ./video.h:6: In file included from /usr/include/c++/4.2.1/vector:73: /usr/include/c++/4.2.1/bits/vector.tcc:252:8: error: no matching constructor for initialization of 'image'       _Tp __x_copy = __x;           ^          ~~~ /usr/include/c++/4.2.1/bits/stl_vector.h:608:4: note: in instantiation of member function 'std::vector<image,   std::allocator<image> >::_M_insert_aux' requested here       _M_insert_aux(end(), __x);       ^ video.cpp:50:10: note: in instantiation of member function 'std::vector<image, std::allocator<image> >::push_back'   requested here             frames.push_back(tempImage);                    ^ ./image.h:25:4: note: candidate constructor not viable: 1st argument ('const value_type' (aka 'const image')) would   lose const qualifier image(image &img); ^ ./image.h:24:4: note: candidate constructor not viable: requires 0 arguments, but 1 was provided image(); ^ ./image.h:26:4: note: candidate constructor not viable: requires 2 arguments, but 1 was provided image(int rows, int columns); ^ 2 errors generated.

Is there a good way in C++ to implement (or fake) a type for a generic vector of vectors?  Ignore the issue of when a vector of vectors is a good idea (unless there's something equivalent which is always better). Assume that it does accurately model the problem, and that a matrix does not accurately model the problem. Assume also that templated functions taking these things as parameters do need to manipulate the structure (e.g. calling push_back), so they can't just take a generic type supporting [][].  What I want to do is:  template<typename T> typedef vector< vector<T> > vecvec;  vecvec<int> intSequences; vecvec<string> stringSequences;   but of course that's not possible, since typedef can't be templated.  #define vecvec(T) vector< vector<T> >   is close, and would save duplicating the type across every templated function which operates on vecvecs, but would not be popular with most C++ programmers.


I live close to a farm and I have access to fresh barley. How would I go forward to create barley malt, so I can brew for example a Pale Ale beer?

My local health food store sells various types of grain, including barley, which are labelled "unprocessed".  So my question is - can I malt this barley and use this in my homebrew? How does one malt barley?  Also, the store has rye and wheat. Can I malt these grains?  OK, so has anyone here actually made an all-grain brew with home-malted barley?


I am hoping to get the flight number of a BA flight from LHR to Sydney Airport (Kingsford smith) leaving LHR on Monday 14th October 1974 and arriving in Sydney on Wednesday 16th October 1974 Travelling via Frankfurt, Tehran, Bombay, Hong Kong and Darwin.

The question  only deals with flights in the US sourced from the  . Is there some similar source for EU, Asia etc?


I ran this script:   and I thought it would deploy my static site blog to my GitHub pages account, but instead deleted almost all of my personal files.   Is there a way to recover this or find the missing links to the indexed files?

I accidentally deleted a file from my laptop. I'm using Fedora. Is it possible to recover the file?


Let $V$ be a finite-dimensional inner product space, and let $E$ be a idempotent linear operator om $V$, i.e. $E^2 = E$. Prove que $E$ is self-adjoint if and only if $EE^*=E^*E$.

I have been trying to solve this problem for quite a while. I am still unsure of whether any of the avenues I have pursued have been of any use. Any advice will be much appreciated. Question: Let $V$ be a finite-dimensional inner product space, and let $E$ be an idempotent linear operator on $V$. Prove that if $EE^* = E^*E$, then $E$ is self-adjoint. (This is essentially exercise 5(a) in sec. 80 on p.162 of Paul R. Halmos, Finite-Dimensional Vector Spaces, but Halmos didn't assume that the dimension of $V$ is finite.)


I have a number of stats and effects in game that are subject to change, they have some kind of base value and the current value. For stats, I implemented this in a dynamic way, but for less important things, like buffs that is too much work. For buffs I have 2 properties - current and base value. For example, the shield buff action takes the base value and copies it into the current value at the start of each turn.  What is a good way to implement having the current value and base value for effects?  Right now I have a base property defined along with the modified value.  +(BuffBase*)buffWithEffectType:(kEffectType)effectType intensity:(int)intensity {     BuffBase* buff = [[BuffBase alloc] init];     buff.intensity = intensity;     buff.baseIntensity = intensity;      return buff; }   Should I refactor such code early on and replace it with some kind of tuple, like EffectValue(current,Base) where x is current and y is base?   +(BuffBase*)buffWithEffectType:(kEffectType)effectType intensity:(int)intensity {     BuffBase* buff = [[BuffBase alloc] init];     buff.intensityTuple = EffectValue(intensity, intensity);     return buff; }   Or should I start with a dictionary/map right from the start? This seems to be the easiest to expand later on, although I have to remember string keys:  +(BuffBase*)buffWithEffectType:(kEffectType)effectType intensity:(int)intensity {     BuffBase* buff = [[BuffBase alloc] init];     NSMutableDictionary* dictionary = [[NSMutableDictionary alloc] init];     [dictionary setObject:@(intensity) forKey:@"base"];     [dictionary setObject:@(intensity) forKey:@"current"];      //optional parameters for potential future expansion     [dictionary setObject:@(1) forKey:@"decay"];     [dictionary setObject:@(4) forKey:@"maxHitsBlocked"];     buff.valueDictionary = dictionary;      return buff; }

Overview:  Lots of games with RPG-like statistics allow for character "buffs", ranging from simple "Deal 25% extra damage" to more complicated things like "Deal 15 damage back to attackers when hit."  The specifics of each type of buff aren't really relevant.  I'm looking for a (presumably object-oriented) way to handle arbitrary buffs.  Details:  In my particular case, I have multiple characters in a turn-based battle environment, so I envisioned buffs being tied to events like "OnTurnStart", "OnReceiveDamage", etc.  Perhaps each buff is a subclass of a main Buff abstract class, where only the relevant events are overloaded.  Then each character could have a vector of buffs currently applied.  Does this solution make sense?  I can certainly see dozens of event types being necessary, it feels like making a new subclass for each buff is overkill, and it doesn't seem to allow for any buff "interactions".  That is, if I wanted to implement a cap on damage boosts so that even if you had 10 different buffs which all give 25% extra damage, you only do 100% extra instead of 250% extra.  And there's more complicated situations that ideally I could control.  I'm sure everyone can come up with examples of how more sophisticated buffs can potentially interact with each other in a way that as a game developer I may not want.  As a relatively inexperienced C++ programmer (I generally have used C in embedded systems), I feel like my solution is simplistic and probably doesn't take full advantage of the object-oriented language.  Thoughts?  Has anyone here designed a fairly robust buff system before?  Edit: Regarding Answer(s):  I selected an answer primarily based on good detail and a solid answer to the question I asked, but reading the responses gave me some more insight.  Perhaps unsurprisingly, the different systems or tweaked systems seem to apply better to certain situations.  What system works best for my game will depend on the types, variance, and number of buffs I intend to be able to apply.  For a game like Diablo 3 (mentioned below), where nearly any bit of equipment can change a buff's strength, the buffs are just character stats system seems like a good idea whenever possible.  For the turn-based situation I'm in, the event-based approach may be more suitable.  In any case, I'm still hoping someone comes along with a fancy "OO" magic bullet which will allow for me to apply a +2 move distance per turn buff, a deal 50% of damage taken back to the attacker buff, and a automatically teleport to a nearby tile when attacked from 3 or more tiles away buff in a single system without turning a +5 strength buff into its own subclass.  I think the closest thing is the answer I marked, but the floor is still open.  Thanks to everyone for the input.


I have a collection of folders that I want to be backed up to OneDrive. As files in these folders change - I want the new files to be uploaded/synced to OneDrive. As the size of these folders is significant, I do not want to physically copy the files to OneDrive folder. Nor do I have an option to install OneDrive folder to be a parent for all the folders that have to be backed up. Essentially I am looking for a basic functionality of any backup product where you just select the folders to backup. Unfortunately the current answers on SuperUser did not answer my question.

I'm trying to take advantage of the fact that OneDrive now offers unlimited space, and allows these files to not take up space locally. I already have a backup system in place, but I would like to add this as an additional offsite backup option.  My photo folder is 200GB+, and I want it to stay on my data drive, and be available offline. I imagine this is a common scenario.  Goals:   Keep my OneDrive on my SSD Keep an offline copy of my files on my data drive Keep an "online-only" copy of my photos in my OneDrive   My first instinct was junction points, but it sounds like they're not supported. Next, I tried Robocopy, but it doesn't like overwriting online-only files.  Is there a way to compare offline files and online-only OneDrive files, and overwrite those files if the source is newer?


In python, I have code like this:  def var(a=1, b=2, c=3):         return a, b, c   Running it gives this outcome:  >>> import Test >>> Test.var() (1, 2, 3)   In this case, 1, 2 and 3 are the default values I want to use. Occasionally, I want to be able to modify all or some of those variables. However, because I have many possible var() statements with different defaults and number of defaults. They can be var(a=1, b=2, c=3) or var(d=1, e=2, f=3, g=4) or var(h=0) and so on.  I want to modify these variables through a single variable I can feed from command line, like this:   >>> arguments = 'a=0, b=5, c=7'   But this doesn't work.  >>> Test.var(arguments) ('a=0, b=5, c=7', 2, 3)   It interprets the 'arguments' variable as being only 'a' while leaving b and c untouched. How can I make my 'arguments' variable be read literally by the def statement?

In the following method definitions, what does the * and ** do for param2?  def foo(param1, *param2): def bar(param1, **param2):


Why does this not produce y tick labels in fixed number format? (pgfplots version 1.9 produces y tick labels in scientific format)  \documentclass[12pt]{article}   \usepackage{pgfplots}  \begin{document}   \begin{tikzpicture}  \begin{axis}[y tick label style={/pgf/number format/fixed}]  \addplot{cos(x)/12.0};  \end{axis} \end{tikzpicture} \end{document}

A chart with data in the range of 200,000 and small difference between max and min values, will be assigned a 10^5 multiplier to the entire axis. This results in the ticks becoming meaningless, since all become 2.   Example:-  \begin{tikzpicture} \begin{axis}   \addplot coordinates {   (100,200001)   (200,200003)   (300,200005)   };     \end{axis} \end{tikzpicture}   When this is plotted the y-axis has 5 ticks, all of which are 2. The y-axis has a multiplier of 10^5. This has effectively removed all information from the graph.  I may use the below to set the explicit value of the tick values but this does not implement change in the display "style" of the axis ticks.  ytick = {200000, 200005, 200010}   I have also tried increasing the precision of the tick label to 5. However this only results in the graph showing labels such as 2.00000, 2.00005, 2.00010 with a 10^5 axis multiplier.  yticklabel style={precision = 5,}   My question is "How do I remove/change this 10^5 multiplier, such that the y-axis ticks are displayed in the form 200000, 200005, 200010.


If i try using Math.Pow in a decimal variable i wont be allowed to do so because it needs to be a double. Is there any way i can print extremely precise powers? Extremely as in at least 50 or a hundred digits

The .net framework provides in the Math class a method for powering double. But by precision requirement I need to raise a decimal to a decimal power [ Pow(decimal a, decimal b) ]. Does the framework have such a function? Does anyone know of a library with this kind of function?


Yes, this is a question that people keep repeating about comparatives, especially with these adjectives: easy, pretty, friendly, lively.   I know the rule about two-syllable adjectives ending in  /i/ or /o/ should get the morphological -er and -est.   Yet, it is evident from different copora that the use of "more easy" and "more friendly" exists, which is not infrequent.  Did anyone come up with an explanation for this or did read any scholarly articles relating to the choice of these different construction of comparatives?

I know the rule for making the comparative and superlative form for two-syllable words ending in y, replace the -y with i and use -er and  -est:    hap.py → happier → (the) happiest ti.dy → tidier → (the) tidiest fun.ny → funnier → (the) funniest  Instead for two-syllable adjectives which do not end in -y, use more and most:    bor.ing → more boring wor.ried → more worried care.ful → more careful tra.gic → more tragic  However, there are inexplicable exceptions: The Free Dictionary says the comparative and superlative form of  is cleverer and cleverest. Yet to my ears     He's more clever than I thought   sounds more formal and correct.  Google produces a total of  for “he is more clever than” and  for the contracted form,  “he's more clever than”. Similarly, Google yields  and  for “he's cleverer than” and “he is cleverer than” respectively, which suggests there is very little to choose between the two comparative forms.  Meanwhile, TFD insists that the comparative and superlative form of  is  simpler and simplest. Google seems to concur and produces  for “it is simpler” compared to only  for “it is more simple”.  The two-syllable adjectives that I am aware of, which have both kinds of comparative and superlative forms are:   clever → cleverer/more clever → cleverest/(the) most clever common → commoner/more common → commonest/(the) most common gentle → gentler/more gentle → gentlest/(the) most gentle humble → humbler/more humble (etc.) hollow → hollower/more hollow  narrow → narrower/more narrow  polite → politer/more polite quiet → quieter/more quiet simple → simpler/more simple stupid → stupider/more stupid subtle → subtler/more subtle   Etymologically speaking, is there any explanation for this?  Is it a recent trend?  It seems to me that the number of two-syllable adjectives that add the suffix -er and -est are increasing.   And finally, is there a trick or rule which I can teach my advanced private students? With younger learners and beginners I teach the “rule” that I mentioned at the beginning—so much simpler! :)    EDIT  December 11, 2019     I shall never ever understand Google's algorithms and how they produce their statistics. In the end, for the sake of clarity, the number of results have been substituted and updated with the number of pages each search produced.


On my current Linux system (Debian Jessie amd64), I'm getting different behavior for dd using /dev/urandom (/dev/random behavior is properly documented). If I naively want 1G of random data:  $ dd if=/dev/urandom of=random.raw bs=1G count=1 0+1 records in 0+1 records out 33554431 bytes (34 MB) copied, 2.2481 s, 14.9 MB/s $ echo $? 0   In this case only 34MB of random data are stored, while if I use multiple reads:  $ dd if=/dev/urandom of=random.raw bs=1M count=1000 1000+0 records in 1000+0 records out 1048576000 bytes (1.0 GB) copied, 70.4749 s, 14.9 MB/s   then I properly get my 1G of random data.  The documentation for /dev/urandom is rather elusive:     A read from the /dev/urandom device will not block waiting for more   entropy.  As a result, if there is not sufficient entropy in the   entropy pool, the returned values are theoretically vulnerable to a   cryptographic attack on the algorithms used by the driver.  Knowledge   of how to do  this  is  not  available  in  the  current unclassified   literature, but it is theoretically possible that such an attack may   exist.  If this is a concern in your application, use /dev/random   instead.   I guess the documentation implies there is some sort of maximum read size for urandom.  I'm also guessing that the size of the entropy pool is 34MB on my system, which would explain why the first read of 1G failed at about 34MB.   But my question is how do I know the size of my entropy pool? Or is dd stopped by another factor (some kind of timing issue associated with urandom?).

I am running the following command on an ubuntu system:  dd if=/dev/random of=rand bs=1K count=2   However, every time I run it, I end up with a file of a different size.  Why is this?  How can I generate a file of a given size filled with random data?


using namespace std; int main() {     float f1 = 5488955, f2 = 0.2197265620, f3 = 0;     f3 = f1 + f2;     f3 = f3 - f1;     cout << f3<<endl;     return 0; }  why f3 value getting printed as 0 but not 0.2197265620

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


If I have a product of matrices of rank 1, the product is not going to have rank greater than 1. why?

Let $A$ and $B$ be two matrices which can be multiplied. Then $$\operatorname{rank}(AB) \leq \operatorname{min}(\operatorname{rank}(A), \operatorname{rank}(B)).$$   I proved $\operatorname{rank}(AB) \leq \operatorname{rank}(B)$ by interpreting $AB$ as a composition of linear maps, observing that $\operatorname{ker}(B) \subseteq \operatorname{ker}(AB)$ and using the kernel-image dimension formula. This also provides, in my opinion, a nice interpretation: if non-stable, under subsequent compositions the kernel can only get bigger, and the image can only get smaller, in a sort of loss of information.  How do you manage $\operatorname{rank}(AB) \leq \operatorname{rank}(A)$? Is there a nice interpretation like the previous one?


I would like to draw an arrow with letter above it using latex just like below:   Thank you for your help.

How can I label $\rightleftarrows$ above the top arrow and below the bottom arrow?


As soon as I have a strip in the Video Sequence Editor it renders from that. How can I choose between rendering from the Video Sequence Editor and rendering the actual Scene?

If you create a scene for the Video Sequence Editor and start working on a project Blender will render the output from the VSE. But if you want to later switch it to render your 3D scene again (the camera output) where is the setting to select the source?  Usually I keep a separate .blend for VSE edits so I don't need to switch, but I feel like I ought to learn how to do this as it's pretty basic. I would expect to find this in the Render context but I see no place to specify the source.  Thanks.


This code below auto-increments based on the FID/OID in the attribute table. How can I auto-increment a column based on a sort of another column? I don't want it to follow the FID/OID. Please advise.  rec=0 def autoIncrement():  global rec  pStart = 1 #adjust start value, if req'd   pInterval = 1 #adjust interval value, if req'd  if (rec == 0):    rec = pStart   else:    rec = rec + pInterval   return rec

I am in ArcMap and I want to sort the records based on a field and then do a Calculate Field with an auto-incrementing value with the sort in-place. Any ideas?    It looks like I could get an update cursor on the feature class then do an auto-increment, but I would still like to see if there is a way to do this in the Field Calculator in ArcMap.


How to install ubuntu 16.10 from 16.04.1 without losing data in / and home folders. i have over 100gb worth apps installed and cannot afford to lose them. need help.

I am planning to upgrade from 8.10 to 10.04. But I am wondering whether there will be data loss during the upgrade.  For example:   Will the applications that I have installed on 8.10 still be there after upgrade? Will the settings of application such as the bookmarks for Firefox and for Google Chrome be preserved? Will all the personal files under my home directory be preserved?   Is there anything else I need to know about upgrading?


My Scizor is currently running Technician but I don't know how it works. I've read about it on Serebii and it says that any moves with a base power of 60 or lower are given a 50% boost. My Scizor has the moves Bullet Punch, Aerial Ace, Fury Cutter and U-Turn and is holding a Choice Band. Bullet Punch has 40 power and STAB makes it 60. Does Technician still boost it? And would the boost be an added 20 power or 30? And if the power is added by 20-30, making Bullet Punch's power 80-90, would the Choice Band raise it to 120-135? And U-Turn's base power is 70 and since it's higher than 60, Technician doesn't work on it, but would STAB make it 105? And would Choice Band raise it to 140-152.5?

A Pokemon which has the Technitian ability gets x1.5 boosted attack power for all moves used which have an attack power of 60 or less (so a move with 60 attack power will actually have 90 attack power). STAB (Same type attack bonus) gives a 50% boost to damage, assuming the attack has the same type as the Pokemon using it (so a Grass Pokemon using Razor Leaf will do 1.5 times the damage). However, I have seen contradicting information, so currently I do not know whether STAB boosts the actual damage or the move's attack power.  What I would like to know, first, is the precise manner in which a STAB is applied to an attack. Secondly, I would like to know what happens if an attack which would be affected by the Technician ability is also affected by STAB (though this answer might vary depending on the actual way that STABs work).  For example, my Scyther has the Technitian ability and attacks using the "Wing Attack" attack, which is a Flying-type attack with 60 attack power. Since Scyther is a Bug/Flying type pokemon he should also get a STAB for this attack, so just what is the eventual attack power/damage in this case?  (Please answer for 4th generation mechanics)


I'm using libgdx trying to make a game, but when I run this from the desktoplauncher, I get a error in the console:  Exception in thread "LWJGL Application" java.lang.NullPointerException     at com.orhantozan.game.PongMain.render(PongMain.java:216)     at com.badlogic.gdx.backends.lwjgl.LwjglApplication.mainLoop(LwjglApplication.java:215)     at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:120)   What is the cause of this? I dont know what the error means :(  Core:   Desktop:   Dew class:

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


I am surprised that some of the most historic universities in continental Europe are ranked above 100 on an average. I specifically have in mind University of Gottingen and University of Vienna. I am assuming that at the peak of their fame, they were rubbing shoulders with the best in the anglo-sphere. What caused the slide in reputation? I have heard that in Germany, Nazism caused the emigration of a lot of talented people. Or is it just that the ranking methodology is biased towards universities in the UK and the US? As someone interested in the history of scientists and scientific institutions, it seems somewhat odd.

I narrowed the outperformed in this question to the US and UK, but please feel free to include other First World nations' universities (eg: Canada, France).    The top American universities didn't really compare to the best in Germany, France, or the UK before then.   inducted this post.


I already have accounts on a bunch of Stack Exchange sites. Mostly when I'm looking at posting on a new SE site, I can see a blue 'Join this Community' button, which gives me a painless "extend my existing account to include this SE" experience.  :+1:  E.g. (stolen from another question):    But on other Stack Exchange sites, I just get regular "Login / SignUp" buttons.  What's the deal here? Is that supposed to happen? Are some SE sites different? If I SignUp with the right credentials, will it all get joined together anyway? What happens if I use some variant of my email-address (e.g. gmail vs googlemail) will I be able to sync the accounts back together after the fact?    For reference, in this particular case it's the Super User SE, but I'm pretty sure I've seen this intermittently elsewhere.

I just visited Ask Ubuntu (askubuntu.com) while logged into Stack Exchange, and noticed that "join this community" doesn't appear:    It is similarly broken on Math Overflow (mathoverflow.net). It works, however, on all sites that are subdomains of stackexchange.com, like Mathematics (math.stackexchange.com) and Academia.  I'm using Google Chrome version 46.0.2490.86 on Windows 8.1 Update 1.  (I don't know if this can actually be fixed, given how cookie security works, but I figured Stack Exchange should be aware of the issue.)


Just to make sure, this is what I mean:  public static void someMethod() {     JButton btn = new JButton();     btn.addActionListener(new ActionListener()     {         public void actionPerformed(ActionEvent e)         {             // Do something...         }     }); }   So when adding an ActionListener to the button, I create a new ActionListener and a new method inside a method - but what is this implementation of an ActionListener called?

What is the use of anonymous classes in Java? Can we say that usage of anonymous class is one of the advantages of Java?


I would like to calculate how much of the land in the European Union exhibits slopes above a certain threshold (let's say 15%) in order to have a precise measure for undevelopable land. I'm working with NUTS-3 level data and would need to match it with some kind of elevation data. I found a few possible data sources for this:     Has anyone worked with this kind of data? I'm a bit lost on how to proceed.

I need to calculate the share of buildable land for the 15 major german cities within a 50 kilometer radius of the city center.  Part 1 of the definition buildable is that the area must have a slope <15% (Part 2 would be being no water surface or wetland, but this might be covered elsewhere). As a student I am completely new to GIS Software and have already tried to mess around with a DEM and the Raster Calculator in ArcMap and QGIS after watching/reading some tutorials but encountered several problems. As my guess/hope is that this should be quite an easy task for an experienced user, I thought I would rather just ask if someone would be very nice and could give me some instructions how to do that first before talking about specific problems in detail(file formats, z-values, ArcGiS Online map..) which may just be there due to a wrong approach in the first place.  Software available would be ArcMap 10.3.1 and QGIS 2.12.3 and the DEM Model used should be 90m resolution or better.  Please recommend a publicly available DEM to use, as I don't have a working one as of now.  In case projections, reference systems, stuff I know not deeply about yet, might lead to different distortions, the results do not need to be extremely precise. Perhaps there is a tutorial where this task is somehow covered?


During fresh installation procedure I get this error:  Error installing /cdrom//pool/main/g/glibc/locales_2.19-18+deb8u2_all.deb trying to overwrite '/usr/sbin/validlocale', which is also in package libc-bin 2.21-0ubuntu4   After closing this error, another one pops up saying the installer has crashed    I booted my laptop from a live USB which has iso of Ubuntu 15.10. I used unetbootin to make the bootable USB.

For example:  $ sudo apt-get install curl Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies: bsh : Depends: libjline-java but it is not going to be installed groovy : Depends: libjline-java but it is not going to be installed rhino : Depends: libjline-java but it is not going to be installed E: Unmet dependencies.   Try 'apt-get -f install' with no packages (or specify a solution).   I get the same or similar errors when I attempt to install clojure1.3, leiningen, and several other packages.   When I try the suggestion made in the error message, this is what happens:  $ sudo apt-get -f install  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   diffstat linux-headers-3.2.0-26-generic linux-headers-3.2.0-26 dh-apparmor dkms html2text libmail-sendmail-perl libsys-hostname-long-perl Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   libjline-java Suggested packages:   libjline-java-doc The following NEW packages will be installed:   libjline-java 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. 23 not fully installed or removed. Need to get 0 B/72.0 kB of archives. After this operation, 129 kB of additional disk space will be used. Do you want to continue [Y/n]? Y (Reading database ... 226243 files and directories currently installed.) Unpacking libjline-java (from .../libjline-java_1.0-1_all.deb) ... dpkg: error processing /var/cache/apt/archives/libjline-java_1.0-1_all.deb (--unpack):  trying to overwrite '/usr/share/java/jline.jar', which is also in package scala 2.9.2-400 Errors were encountered while processing:  /var/cache/apt/archives/libjline-java_1.0-1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  $ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  bsh : Depends: libjline-java but it is not installed  groovy : Depends: libjline-java but it is not installed  rhino : Depends: libjline-java but it is not installed E: Unmet dependencies. Try using -f.


I want to make a script in python 3(preferably) in which I get an "input()" from the user, but the user may or may not give the input. So it should wait for some fixed time and if no input is given in that time follow default condition already set.  I have no idea, if there are any keywords I should search for.

I'm calling a function in Python which I know may stall and force me to restart the script.   How do I call the function or what do I wrap it in so that if it takes longer than 5 seconds the script cancels it and does something else?


For sake of question, we are UK based.  Myself and fiancée are looking to book our honeymoon for September this year to Singapore.  She will be taking my surname after the wedding.  The issue is that her passport, which is in her maiden name, expires in May, and we do not get married until June.  We do not want to pay to renew her current passport, and then have to pay again to change her name after the wedding.  If her passport was not due to expire, we would have just booked it in her maiden name and changed her name on the passport after the honeymoon.  If we were to book the honeymoon via Expedia, with flights via Qatar Airways, would this be safe enough to do by using her name with my surname, and then apply for the new passport after the wedding seeing as there are 2 full months between the wedding and travel date?

In many countries, the wife takes the husband name after getting married.  Let's say that a woman changes her last name, but she had a booking using her previous last name. She also has a marriage certificate and a document that shows that she had another last name before marriage.  Questions:   Is the booking valid? Does she need to change the name in the booking system before check-in? Is this paid or is it for free? If the check-in was already performed and the boarding pass was generated, can she use the boarding pass in the airport together with her new ID + the marriage certificate + the document that attests her surname change?   Details:   the companies are from Europe (low-cost) the flights are inside Europe


I think since $F=ma$ thus the frictional force can produce acceleration in a body in some cases, is my view correct?please suggest some example then. If not then where i went wrong?

Can work done by friction be positive? Please explain with an example. Is the work done by friction on a moving car positive?


So i'm trying to display a TextView whenever a user clicks an item on a ListView. However, when i click a list item, i get this error... java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference. What causes this to occur in regards to "TextViews" specifically and are there any possible solutions to solving it? Thanks. Update Here's how i set the TextViews.. Activity @Override public void onTextFooterListener(String String1, String String2) {      tab1.setLabels(String1, String2);  }  Tab1Fragment public void setLabels(String mString1, String mString2) {      title1 = mString1;     title2= mString2;      title1Footer.setText(title1);     title2Footer.setText(title2);     updateTimerLabel(); }  TextViews title1Footer= (TextView) rootView.findViewById(R.id.title1_footer); title2Footer= (TextView) rootView.findViewById(R.id.title2_footer);  tab1 is declared as public Tab1Fragment tab1 = new Tab1Fragment(); If i comment out the onTextFooterListener, the code seems to work just fine...

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


I have recently been reading Intro to Lie algebras and representation theory by Humphreys, and when I am finished I am interested in reading about Lie groups and Lie algebras and their applications to particle physics.     Is there a book that assumes basic knowledge of Lie algebras, and no knowledge of lie groups and particle physics/quantum mechanics?   I have seen Howard Georgi's book, but it assumes good knowledge of particle physics.   In addition, I do not know differential geometry.

I am looking for a good source on group theory aimed at physicists. I'd prefer one with a good general introduction to group theory, not just focusing on Lie groups or crystal groups but one that covers "all" the basics, and then, in addition, talks about the specific subjects of group theory relevant to physicists, i.e. also some stuff on representations etc.  Is Wigner's text a good way to start? I guess it's a "classic", but I fear that its notation might be a bit outdated?


I want the player to be teleported when they reach y=0. I tried the /execute command and it didn't work.

I am trying to teleport a player to certain coordinates once they enter an area.  The idea is that they walk into a really small building, but once they turn a corner, they get teleported into a larger building.   Please refer to the adventure map named '5 Cubed', if you need help understanding what I am asking.


I am modeling a phillips head screw. What would be the best way to do this? I need to make the top look realistic. Are there any good textures for this? My current design:

I want to make a screw head, but I can't get the cross in the screw head; the Boolean modifier doesn't work.  Link:


How to calculate the number of subgroups of a group whose order is $19$? Normally, I'd resolve this problem with the Lagrange's Theorem, but I don't know how to do it with this one because I only know the order. So this is not the best approach. What's the answer to this problem? Thanks.

So let's say that I have a group of order $p$, where p is prime; does that group only have one subgroup?   I've look at the wiki article and it says there's a trivial and actual solution, so can we somewhat say it is only one group that exists.   I apologize if I am misinterpreting this.   Thanks for the time and help.


I'm making a shallow hemisphere for a 3d printing project. I have to add some "depth" to the hemisphere for the printer to be happy so I made a copy of the current object and shrunk it down a bit. In order to close the shape up I need to add faces to hold these two objects together.  I selected the edges of both hemispheres but when I type "F" it fills each hemisphere independently to itself. I've bool > union these two hemispheres together thinking that would help but it hasn't.  How can I get these two circular shapes to close together making one shape rather than having them close independently making two overlapping shapes?  This is my first 3d project from blender so if there is a better way to be doing this please let me know. Cheers.

Hey I want to connect the bottom loop with the top loop so that it forms a solid.  I have tried selecting multiple vertices and pressing F but that just creates a large face which I do not want. I have tried using grid fill bu that doesn't work either. The solution that seems to work is by selecting four vertices and pressing F and then selecting the next 4 and pressing F and on and on. That just takes too long.


I have made a figure using TikZ and I want it to be inside a subsection after a few sentences, as shown in the following:  \newpage     \section{Modeling}     \subsection{Modeling Trajectory}     This subsection's content...     at this point I will....  \begin{figure} \begin{center}     \begin{tikzpicture}     \draw[thick,->] (0,0) -- (6,0) node[anchor=north west] {x};     \draw[thick,->] (0,0) -- (0,6) node[anchor=south east] {y};     \draw[thick,->] (3,3) -- (5,2) node[anchor=north west] {$V_{T}$};     \draw[thick,->] (3,3) -- (1,4) node[anchor=south west] {$F_{Drag}$};     \draw[thick,->] (3,3) -- (3,1) node[anchor=north west] {g};     \draw [dashed] (3,3) -- (6,3);     \draw (4,3) arc (0:-28:1) node[] at (30:5.3)  {$\gamma_{T}$};     \end{tikzpicture}     \caption{Ballistic target geometry} \end{center} \end{figure}   However, what I get is that the figure at the top of the page, then the section title and the the subsection title.  The result I needed is:  section title subsection title figure   I tried using \floatbarrier but it moves the whole figure to the center of other page.  Thank you.

How to influence the position of float environments like figure and table in LaTeX?   This is a general question and should collect useful answers for all users. I hope we can use this as a reference


I'm typesetting a thesis using a custom class based on book class and to meet the university requirements, all pages in frontmatter must not show the page numbers but must be counted, starting at the cover. I was able to change everything, except for the list of symbols and list of abbreviations and acronyms, that were made with the nomencl package.  I tried the solution in this post , but using that one, the entry in the toc does not show any page number. I need just to hide the page number of the lists. How can this be accomplished?

I have a problem and I want that someone tell me how I can resolve that.  I want that the number of page in my report start in the page of introduction but in reality it starts in the didecas and liste of contents. I want that these pages have not number. This is my code  \documentclass[12pt,a4paper]{report} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage[french]{babel} \usepackage{color} \usepackage{xcolor} %les couleurs \definecolor{myblue}{rgb}{0.2,0.4,1} \usepackage{layout} \usepackage[top=2 cm, bottom=2 cm, left=2 cm, right=2 cm]{geometry} \usepackage{setspace} \usepackage[pdftex]{graphicx} \usepackage{array} %\documentclass[landscape]{scrartcl} \usepackage{geometry} \usepackage{multirow}  \usepackage[justification=centering]{caption}  \usepackage{pgfplots}   \usepackage{fancyhdr} \fancyhf{} % clear all header and footers   \begin{document} \pagestyle{empty} \include{title-content} \color{black} \doublespacing \include{dedicaces-content} %\include{remerciement}   \tableofcontents  \listoffigures \listoftables     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \pagestyle{plain}  \pagenumbering{arabic} \chapter{Introduction générale}


I configured a pin on my micro-controller(STM32F4-discovery) as an open drain and I wanted to connect it to a 5V pull-up network and drive an LED. The output of my pin is 3V so hence I wanted to pull up the pin to another voltage if I have another device that requires 5V. I am using an LED as an example to test the proof of concept, but I am confused that why it wouldn't work:    I have also been reading about Logic Level Converter recently where it can "convert" your 3V to 5V. Should I be using that instead?

I need to drive an LED from an .  So I was thinking about a classic circuit with a BJT.  But then I saw that GPIO outputs of the microcontroller are configurable as open drain.  Would this circuit work?    The LED has a 20mA forward current and a 2V forward voltage. Considering \$R=(3.3-2)/0.02\$ it should be on, if GPIO is Hi-Z and off, if it is GND, right?  I don't see why this circuit would not work but I've never seen it before, so I just want to be sure before designing it.  Edit: Then you mean it is better to do this:    Edit 2: Finally here is the schematic I'll be using (the output GPIO LED6FAIL is 3.3V and it's a push-pull):


I am using photoshop to design a t shirt..  As for the photo to look like reality I have taken a picture of a t shirt which has wrinkles. Now when I keep my Image(design) on the tshirt, it is looking like that I have kept a design. But I want the design to adjust in a way that it will adjust according to the wrinkles. I have given an example having an examples which shows both the design which I want to design(downloaded)   Note: Green Circles: shows the image adjustment according to the t shirt..  For more information just give a comment and I will respond in seconds.....

I created a depth map based on an image of the back of a man wearing a coat. Now I want to apply an image to the depth map, giving the appearance that the image part of the jacket. How is this done?


I was calculating the probability to draw all items in a list of N items, by picking one randomly, replacing it in the list, etc. (Edit: It's the Coupon collector Problem)  I found  after n picking.  $$ \sum_{i=0}^N (-1)^{N-i}{\binom{N}{i}}\left(\frac{i}{N}\right)^n $$  But, I have to calculate this formula with N > 1000000000 in a java program so to avoid a huge loop (the sum). I'm looking for a simplification, any approximation formula will help me.

I heard an interesting question recently:     What is the minimum number of people required to make it more likely than not that all 365 possible birthdays are covered?   Monte Carlo simulation suggests 2287 ($\pm 1$, I think).  More generally, with $p$ people, what is the probability that for each of the 365 days of the year, there is at least one person in the group with that birthday?  (Yes, ignoring the leap-day.)


My question is about whether you can convert the pressure something has to the velocity it will have. For example, if I had water shooting out of a hose at 100PSI, could I calculate the speed that the water would have after it leaves the hose? Is that possible to calculate with just pressure, or would you need more information?

The question I'm asking is pretty much:  How do you convert PSI to Velocity?  Everywhere I look it says You can't, but can you?  And what would you need to know to do so if there is no direct way to convert?  My homework is to convert 0.14 PSI into m/s.  EDIT Sorry guys my teacher does like being tricky, no clue why. Sorry for any inconvenience this may have caused.


I use a 13.04 system. Whenever the system boots up, the Bluetooth button is by default ON..Every time i have to manually disable it.Is there any way to disable this?

How can I deactivate Bluetooth on system startup?


I have a Security camera that on it's box it said DC 12V , 10.5W MAX / PoE(802.3af) by the word "Max" they mean I can use lower watts ? I still didn't connect any DC's and waiting for your help can I use 12 1A, lower or higher?  Can I use 12V/1A adapter?  Thanks Saar

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


I’m not sure which one is correct ? Drive into the driveway or drive onto the drive way ? Thanks.

Do we use in or on when we want to talk about some action or event that takes place in/on the street?        This car has been parked [in/on] our street for a week now.   There's nobody [in/on] the street.   Let's go play [in/on] the street.   There was an accident [in/on] their street yesterday.   I guess I lost my necklace [in/on] the street.      And so on.


First law states that energy can neither be created nor be destroyed. So how did the big bang gathered so much energy to expode?

Did the law of conservation of energy apply to the earliest moments of the Big Bang? If so, what theoretical physics supports this?   I hear that Einstein's theory of relativity disputes the law of conservation of energy- so does that mean the law is false, or only some aspect of it?


There is a professor in Department X. I will be applying to Department Y & Department Z for a MA that really fits my interests. Now, I am wondering whether the professor in Department X will also hold classes in Department Y & Z, or whether these classes are shared and accessible over multiple departments anyways (how does this usually work in the UK? I don't really know). How do I ask him this question, how do I best phrase it? I am a bit unsure about this. Right now I have  I am currently thinking of applying for X at Uni X, and am wondering whether I could then attend your courses too?   but it sounds a bit strange to me? (English is not my native language)

When needing to ask a professor about something important and potentially delicate, what is an appropriate way to phrase the question or write the email?  Examples include:   Requesting a recommendation letter Asking for exceptions to policy (e.g., ignoring a course prerequisite, rescheduling an exam) Asking if you can do research with them, join a group, get into a program Scheduling a meeting, exam, or defense Letting them know about a change of plans Letting them know about a life event affecting your work or studies (e.g., wedding, funeral, sickness, vacation)


I'm trying to edit a value in a 2D array.   Just the value at [0][0] but when I edit it, it propagates to all the values at [x][0] and I don't understand why.   I then copied the exact line from an example that I found online and it works but I don't understand what the difference is.   I simplified both examples and they still don't have the same solutions. This doesn't add up.   counter= 3*[4*[0]] counter[0][3] = 7 print(counter)  T = [[0, 0, 0, 0], [0, 0,0,0], [0, 0, 0, 0]] T[0][3] = 7 print(T)   the top print statement gives: [[0, 0, 0, 7], [0, 0, 0, 7], [0, 0, 0, 7]]  the bottom gives:  [[0, 0, 0, 7], [0, 0, 0, 0], [0, 0, 0, 0]]  but they should be the same.

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


My boss asked me to submit my research to a journal I've never heard of.  How do I know that journal is good for my career apart from the impact factor?  I would like to have my own criteria without just doing whatever my boss says. For example, how the journal is peer-reviewed, time of publication, specific topics, other authors, and how to measure these things just looking at a journal site.

A colleague and I recently submitted a paper to a journal with an impressive-sounding name, the "International Journal of Artificial Intelligence and Computational Research". According to ,      IJAICR is a referred [sic] journal in the field of computer science, artificial intelligence and soft computing methods.   It was accepted two days after we submitted it. That's too fast. We were suspicious. Although the journal said that all papers are peer-reviewed, we could not see how that was done in two days. Plus, we received no comments from the reviewers. Also, the submission guidelines didn't ask for a "blind" copy (without our names or any references to who we were).   But wait, there's more.  The acceptance letter asked us to send them US$300 to publish it. We did not. We've withdrawn our submission and will submit a new version of the paper to a more reputable journal in the coming months.  How might we make a better choice of respectable journals before we submit next time?


I am sure there is a better way or writing this python function:  end_points = list(range(100)) filepath = 'something.csv' with open(filepath) as fp:     cnt = 0     for line in fp:         end_points[cnt]=[x.strip() for x in line.split(',')]         cnt += 1   It works but it is not elegant. Is there a way of automatically refers to the current number of iteration in the for loop?

How do I access the index in a for loop like the following?  ints = [8, 23, 45, 12, 78] for i in ints:     print('item #{} = {}'.format(???, i))   I want to get this output:  item #1 = 8 item #2 = 23 item #3 = 45 item #4 = 12 item #5 = 78   When I loop through it using a for loop, how do I access the loop index, from 1 to 5 in this case?


The entire episode is about Wesley accidently walking on the Edo's grass, violating their laws in the process, and incurring the death penalty. Picard is concerned about violating the prime directive because he feels that if he doesn't abide by Edo law he is interfering in the affairs of another species.   However, isn't part of the prime directive that they don't make first contact with non-warp capable species? I thought that contact of that nature was considered detrimental to the natural development of non-warp species. We see an example of this in the Edo's view of god, the Enterprise sharing space with god, etc. So why is Picard so concerned about violating the prime directive in regards to saving Wesley when it appears that visiting a planet of a non-warp capable species for the sole purpose of shore leave and no attempt to conceal their identities or capabilities is a violation in the first place.

In a first season episode of Star Trek: The Next Generation the Enterprise visits a planet named Rubicun III where () the Edo live.  It is often mentioned in Star Trek that the Prime Directive requires that pre-Warp civilisations be ignored until they discover Warp mechanics. But this planet and civilisation appears to be exempt from that status. Why?


I would like to format some Python code using lstlistings and have function and class definitions in bold, i.e. anything that follows the word class or def. I don't want to individually define the keywords however, as when the functions are called they shouldn't be bold.  MWE:  \documentclass{article} \usepackage[T1]{fontenc} \usepackage[lighttt]{lmodern} % bold and italic ttfamily \usepackage{color} \usepackage{listings} \usepackage{setspace}  \definecolor{Code}{rgb}{0.1,0.1,0.1} \definecolor{Decorators}{rgb}{0.7,0,0.7} \definecolor{Numbers}{rgb}{0.5,0,0} \definecolor{MatchingBrackets}{rgb}{0.25,0.5,0.5} \definecolor{Keywords}{rgb}{0,0,1} \definecolor{self}{rgb}{.87,.46,0} \definecolor{Strings}{rgb}{0,0.66,0} \definecolor{Comments}{rgb}{0.388,0.4705,0.518} \definecolor{Backquotes}{rgb}{0,0,0} \definecolor{Classname}{rgb}{0,0,0} \definecolor{FunctionName}{rgb}{0,0,0} \definecolor{Operators}{rgb}{0,0,0} \definecolor{Background}{rgb}{0.99,0.99,0.99}  \lstset{ language=Python, numbers=left, numberstyle=\footnotesize, numbersep=1em, xleftmargin=3em, linewidth=23cm, framextopmargin=1em, framexbottommargin=1em, showspaces=false, showtabs=false, showstringspaces=false, frame=l, tabsize=4, % Basic basicstyle=\ttfamily\small, backgroundcolor=\color{Background}, % Comments commentstyle=\color{Comments}\slshape, % Strings stringstyle=\color{Strings}, morecomment=[s][\color{Strings}]{"""}{"""}, morecomment=[s][\color{Strings}]{'''}{'''}, % keywords keywordstyle={\color{Keywords}\bfseries}, % additional keywords keywordstyle={[2]\color{Decorators}}, emph={self}, emphstyle={\color{self}\slshape}, }%      \begin{document} \lstset{language=Python, breaklines=true} \begin{lstlisting}     class MyClass:         def __init__(self):             print('do a thing')      foo = MyClass() \end{lstlisting}  \end{document}   This produces     I would like the first instance of MyClass (following keyword class) and __init__ (following def) to be bold, but the second instance of MyClass should be as shown. How would I go about doing that?  Note that only the word between the keyword and the : or the ( should be bold.  EDIT: I've tried adding  \lstset{moredelim=[s][\bfseries]{class }{:},     moredelim=[s][\bfseries]{def }{(},}   with no luck

I want to implement a function name color highlighting and I use the listings package. My 'regex' for this is def %s( where def (including space) is the first delimiter %s is the function name and ( is the second delimtier. Now my aim is to color only %s in purple. So basically I want to only touch the part between the delimiters and the delimiters should stay untouched.  Here is what I tried so far:  \documentclass{article} \usepackage{xcolor,listings} \usepackage[ngerman]{babel} \usepackage{fontspec} \setmonofont{Courier New}  \begin{document}  \lstset{language=Python,     escapebegin=\color{orange},     keywordstyle=\color{blue}\bfseries,     commentstyle=\color{orange!80!red},     stringstyle=\ttfamily\color{gray},     %moredelim = [is][\color{blue}\bfseries def \mdseries\color{purple}]{def\ }{(},     moredelim = [s][\color{purple}]{def\ }{(},     showstringspaces=false} \lstset{literate=%    *{0}{{{\color{red}0}}}1     {1}{{{\color{red}1}}}1     {2}{{{\color{red}2}}}1     {3}{{{\color{red}3}}}1     {4}{{{\color{red}4}}}1     {5}{{{\color{red}5}}}1     {6}{{{\color{red}6}}}1     {7}{{{\color{red}7}}}1     {8}{{{\color{red}8}}}1     {9}{{{\color{red}9}}}1 }  \begin{lstlisting}[basicstyle=\ttfamily,mathescape] def fancy_function_name(page_url = 'tex.stackexchange.com'):     return page_url.split('.')[0] \end{lstlisting}  \end{document}   This code will generate:   You can see that it matches the right place but is too greedy and colors the delimiters too. So I thought about the uncommented line: %moredelim = [is][\color{blue}\bfseries def \mdseries\color{purple}]{def\ }{(}, If I use this one and uncomment the line below I get this result:    It's nearly what I wan't but I cannot add the last, now missing ( in black color.  Does anyone has a solution for this without pretouching the code and add all the @@ symbols?


sudo dpkg --configure -a    On typing this command I am not able to resolve the problem   dpkg-was-interrupted-run-sudo-dpkg-configure-a    and the terminal window gets hanged. On CLTR + Z it says [2]+ stopped

Whenever I am trying to get the update I am getting the error at the last line:  Ign http://in.archive.ubuntu.com trusty-updates/multiverse Translation-en_IN Ign http://in.archive.ubuntu.com trusty-updates/restricted Translation-en_IN Ign http://in.archive.ubuntu.com trusty-updates/universe Translation-en_IN Ign http://in.archive.ubuntu.com trusty-backports/main Translation-en_IN Ign http://in.archive.ubuntu.com trusty-backports/multiverse Translation-en_IN Ign http://in.archive.ubuntu.com trusty-backports/restricted Translation-en_IN Ign http://in.archive.ubuntu.com trusty-backports/universe Translation-en_IN E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem.   And then according to the prompted error when I run:  $ sudo dpkg --configure -a dpkg: error: parsing file '/var/lib/dpkg/updates/0009' near line 0:  newline in field name `#padding'   What now? Can I get out of the error?  I tried this .


I'm learning finite fields behind Advance Encryption Standard. As far as I know, the irreducible polynomial used in AES is $x^8+x^4+x^3+x+1$. This is because AES s-box is based on bytes(8bits). Now I am trying to enlarge the s-box to 4bytes(32bits), so I need to find a polynomials of degree 32 over $Z_2[x]$. So the question is How can i get a irreducible polynomials of degree 32 over $Z_2[x]$? I've searched for some approaches and not very familiar with trace most mentioned. What materials relating $Z_2[x]$ can I refer to? Besides, I would appreciate it if there is some constructed such polynomials for me to test! Thanks!

What algorithm can be used find an irreducible polynomial of degree $n$ over the field $GF(p)$ for prime $p$. The reason I ask is I want to make a program for finite field arithmetic, but creating a field $GF(p^k)$ requires finding a irreducible polynomial. (I'm mostly interested in $GF(2^k)$.)


I have problems with emails sended by salesforce to users and Office 365. The Office 365 admin block all the salesforce automatic email because they are sended from a @company.com address. To prevent fraud I need to send ALL automatic emails from a fixed address, for example salesforce@gmail.com

I have an email service which parses responses if my customers send emails to the Salesforce generated email.  I want to know whether it is possible to send out emails from the Salesforce generated email address (using our email templates)?


In shell script, If no variables are listed after the read command, a default variable: REPLY will be assigned all the input       $ read     test     $ echo $REPLY     test   Nevertheless, in python       In [1]: input(": ")     : test     Out[1]: 'test'     In [2]: #it's gone   Where could I find the 'test'?

In many symbolic math systems, such as Matlab or Mathematica, you can use a variable like Ans or % to retrieve the last computed value. Is there a similar facility in the Python shell?


I recently read that the mass that we deal with in the equation $F=M_{i}a$ is called the inertial mass and the mass that we deal with in $F=M_{g}g$ is called the gravitational mass.   I find a hard time understanding why we need these two different names. It's the stuff that makes up the ball that is responsible for pulling it towards the ground when dropped from a height and it is the same stuff responsible in determining how hard I should push it if I want to accelerate it on a level plane. So, why do we need to invent two different notions of mass in the first place? What is the fundamental difference between the gravitational mass and the inertial mass that one should not apriori ignore?   I have also read that the inertial mass and the gravitational mass are equivalent to each other and the general theory of relativity is based on this result. So, I feel that there must be physical meaning to the equality of these two masses--they shouldn't be trivially equal to each other. How can a fruitful physical theory (the general theory of relativity) be based on the equivalence between the two masses if they can be assumed equivalent apriori? In other words, I want to say that the equality between the two masses must be a physical result in order for a theory to stem out of it--it cannot be a trivial mathematical identity (otherwise, it would be physically unfruitful). So, what is it that makes these two distinct concepts necessary in the first place and what forces upon us their equivalence?

I have learned in my physics classes about five different types of  and I am confused about the differences between them.  What's the difference between the five masses:    inertial mass,  gravitational mass, rest mass, invariant mass, relativistic mass?


I want to change the value from 1521 to 1525 in FROM_HOST only in file gexhosts.cat:  FROM_HOST   db201521 TO_HOST     db201521   Is there a way to do that or some work around?  I would really prefer if we could use sed as I am using sed for many other activities of mine.

Replacing strings in files based on certain search criteria is a very common task. How can I    replace string foo with bar in all files in the current directory? do the same recursively for sub directories? replace only if the file name matches another string? replace only if the string is found in a certain context? replace if the string is on a certain line number? replace multiple strings with the same replacement replace multiple strings with different replacements


Some people say that 0 is neither even nor odd. I say that 0 is even.  Is there a simple way to convince people that 0 is even and the statement that "0 is neither even nor odd" is false.

Some books say that even numbers start from $2$ but if you consider the number line concept, I think zero($0$) should be even because it is in between $-1$ and $+1$ (i.e in between two odd numbers). What is the real answer?


Can somebody help me? I’m new to Ubuntu, and I need help elevating my privileges to root. All I’m getting is:   darion@darion-HP-2000-Notebook-PC:~$ sudo -i nautilus [sudo] password for darion:   (nautilus:3306): Gtk-WARNING **: Failed to register client: GDBus.Error:org.freedesktop.DBus. Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files  (nautilus:3306): GLib-GObject-WARNING **: invalid cast from 'GtkMessageDialog' to 'NautilusWindow' ** ERROR:nautilus-window.c:2116:nautilus_window_get_slots: assertion failed:(NAUTILUS_IS_WINDOW (window))

I've been using gksudo nautilus and sudo nautilus through Alt+F2.   What's the difference? They look very similar!


How did Planck solve the UV catastrophe? From online sources, I've seen that this had to do with quantization of energy. Somehow I cannot wrap my head around this.   Can any of you please explain? Thank you for your time :)

Max Planck, arguably the leading theoretical Physicist of his day, apparently used of experimental data to formulate his equation for , which was a major step in the birth of quantum mechanics. For this seminal event of the 20th century, I would expect a detailed explanation of how Planck arrived at his conclusion that energy MUST be quantized. I've even read his Nobel lecture but was non the wiser.  Can some kind person please explain it, or give me even just a hint?


As of late,i have had some real wireless USB problems and i've decided to just try and use the piggyback-a-laptop method, i have an Ethernet cord, a ubuntu 15.04 Desktop and a Peppermint 5 laptop.  i've tried the usual methods, i have not done any IP address and i am kinda frustrated.  ALL help is greatly appreciated

I have had some  wireless USB problems and I have decided to just try and use the piggyback-a-laptop method.I have an Ethernet cord, a Ubuntu 15.04 Desktop and a Peppermint 5 laptop.I have tried the usual methods, I have not done any IP address and I am kinda frustrated, I've heard stuff about gateway problems, I might go crawling back to windows after 6 years of Linux  All help is greatly appreciated


Say I asked a question that gained some attention but also want to not be connected to the question in case my workplace stumbles upon it since it questions the company I'm working for.   How can I remove my connection to this question?

The Creative Commons FAQ      Third, if the licensor does not like how the material has been modified or used, CC licenses require that the licensee remove the attribution information upon request [...]  in 4.0, this also applies to the unmodified work.   How do I remove / dissociate my name from a post, in accordance with this clause?  Also, what are the effects of having my post dissociated from my account?  Finally, how will dissociation requests be handled for posts licensed under earlier versions of the license, which do not require dissociation upon request in all cases?


I have 2 questions.  First I am working on an application that gets persons' information from my server so what is the best way to get images from server.   Second should i download images to my storages and then recieve them from my phone's storage to my application. Thank you in advance.  Edit :  I want to do that with all information i parse such as phone number, gender... So what should i do exactly ?

I am using a ListView to display some images and captions associated with those images. I am getting the images from the Internet. Is there a way to lazy load images so while the text displays, the UI is not blocked and images are displayed as they are downloaded?   The total number of images is not fixed.


I have an Atari 1040ST with a half-bad power supply - Along with two 5v Red wires that Are good, there is a Blue wire that requires 12v .9A (aka 9mA??) - With A/c on, it's measuring at 10.73v (on the Blue wire, if you also have an Atari) causing my machine to cycle the Floppy drive when powered up to a beat of "we will rock you" steady clicking so, I'm pretty sure 10.73v is causing that - I have an external adapter that is 12v but 1.25A and another one that is 12v but .41A - I was reading one of the contributors here, Insta's answer which leads me to think I should use the 1.25A and definitely Not the .41A adapter - I will be splicing in to the Black Ground wire (there are 3 of these, I'll just pick one) and I will Cut the Blue and Splice the + going to that pin, bypassing the Atari PS altogether - I will then have the A/C AND the DC adapter on a Surge suppressor so that they power up at the same time - Should/Can I use the 1.25A adapter is my long question (sorry 'bout that!)

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


This is not a question about transferring from one iOS device to another (straightforward and addressed at length in . This is a question about transferring from one Game Center account to another. It happens that in my case this is within a given device.  My kid has started to play Clash of Clans on my iPad - under my own Game Center account.   Now I have reconfigured this iPad for him to use, with his own account (which I created in order to use the Family Sharing features.   How do I transfer his CoC village from my Game Center account to his?

I have two iPhones and an iPad 2. One of the phones is an iPhone 3GS running iOS 6.1.6 and the other is an iPhone 4 running iOS 7. Under the same Game Center account they each have a separate village for Clash of Clans. I just got my iPad and wanted to transfer the game on the iOS 6.1.6 device to my iPad. What I was wondering was, if it's even possible to link a game on Clash of Clans from an iOS 6 device to an iOS 7 device, and if so how do I do so?


using System.Collections; using System.Collections.Generic; using UnityEngine;  public class PlayerMovement : MonoBehaviour {      public CharacterController2D controller;      public float runSpeed = 40f;      private float horizontalMove = 0f;      // Update is called once per frame     void Update () {         horizontalMove = Input.GetAxisRaw("Horizontal")*runSpeed;     }      void FixedUpdate(){         controller.Move(horizontalMove*Time.fixedDeltaTime,false,false);//error is somewhere here     } }   Though all the classes are defines it throws the error please help!!!!!

Since many users are facing the NullReferenceException: Object reference not set to an instance of an object error in Unity, I thought that it would be a good idea to gather from multiple source some explanation and ways to fix this error.  Symptoms I am getting the error below appearing in my console, what does it mean and how do I fix it?  NullReferenceException: Object reference not set to an instance of an object


Is it possible to create a lens shader with EEVEE/Cycles ? I'd like to have the control over the camera position and the ray direction per sample. This allows to simulate various conventional lens distortions (which I'm not interested in) and other deforming effects. Houdini and Arnold supports a camera lens shader, someone also used it to run across the objects and bake textures. Some other ideas include run a particle simulation, and assign each particle to a pixel in the image as if it were a camera looking from that particle. Or you can just use an ordinary object to sample the space around. You can mix perspective and orthographic in different parts of the image, blending between them, or even zoom only part of the image. This thread shows how to set it up and one possible use that this kind of level of control gives you.  I insist that I'm not trying to replicate this specific effect, I'm looking for this level of control per pixel.

I'm curious if a shader can be made for a flat square that can act as an optical lens. In the shader  be able to set a f factor, to set focus strength distance.


I've used  String[] red = linija.split("(?!^)");   and now in this String array I want to know if red[0] is "/". Tried (red[0] == "/") and with "//", please help.

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


How can I rearrange the order of columns in my attribute table?  I'm inputting a lot of data and would prefer to not have to scroll all the way to the end of my columns for each new entry.  Ideally i'd like to be able to just filter out the columns i don't need to view for this task.

Using QGIS 2.10.1, I open an attribute table.  How do I rearrange the field display order?  For example, a table's default display order (from left to right) is State, County, City.  But I would like to see them displayed as City, State, County.  I'm not interested in rearranging the table's internal structure, rather just the table's display.


i am a beginner in Ubuntu and currently using Ubuntu 19.10 in terminal i used   apt-get update   and this error showed up  Reading package lists... Done E: Could not open lock file /var/lib/apt/lists/lock - open (13: Permission denied) E: Unable to lock directory /var/lib/apt/lists/ W: Problem unlinking the file /var/cache/apt/pkgcache.bin - RemoveCaches (13: Permission denied) W: Problem unlinking the file /var/cache/apt/srcpkgcache.bin - RemoveCaches (13: Permission denied)   how to solve this issue? i am using Ubuntu 19.10 on VMware Workstation 15 Pro and updated it at first lunch by using the "Software Update"

I get this error whenever I try to install programs using the terminal:  home@ubuntu:~$ apt-get install myunity E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied) E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?   Also I'm unable to install updates using the terminal.


We have 3  independent Bernoulli random variables with parameter 1/2. They are pairwise independent but not mutually independent. I know that the variance of Var[A] = Var[B] = Var [C] = 0.25 due to the formula of Bernoulli random variables variance: p * (1-p). Therefore, I know that Var[A] + Var[B] + Var [C] = 0.75. I know as well that Var[A + B + C] = 0.75 because Var[A + B + C] = Var[A] + Var[B] + Var [C] when the variables are pairwise independent.  However, I am not able to calculate by myself Var[A + B + C]. Can you please guide mr algebraically?   Thanks

I know that this relationship is correct when A,B and C are pairwise independent. However, I'm finding it difficult to calculate it.  Let's say that: Var [A] = Var [B] = Var [C] = 0.25. How can I prove that Var[A+B+C] = 0.75?  I started to work with the formula: Var[A+B+C] =E[(A+B+C)^2]−(E[A+B+C])^2 but I got stuck.  Thanks!


I want to append the following line to a text file with sed:  gem 'forum2discourse'   I've tried sed -i '$a gem \'forum2discourse\'' Gemfile but this drops me to a > prompt so I think I must be incorrectly escaping the ' characters

I have a file that contains multiple lines of xml. I would like to replace certain parts of the file. Some parts of the file contains quotation marks (") which I would like to replace. I have been trying to escape the quotation mark with \, but I don't think this is working based on the result of my file.  Here is an example of one of my sed commands:  sed -e "s/\"text\"/'text'/ig" file.xml > temp.tmp   Is this how you escape quotation marks in a sed command or am I doing something wrong?


I am new to Regular Expressions and trying to create one for a specific requirement per below :    Must starts with letters a-Z or A-Z Can contain numbers 0-9 Can contain only allowed special characters i.e. @.-' Only one occurrence of above special characters is allowed i.e. test9@my.com or new-test10@me.com is valid but test5@new@com is invalid    I have tried below code but not able to fulfill all requirements -   var myregex = /^([a-zA-Z0-9@.\-'])*$/; if(!myregex.test(userIdVal)){     alert('invalid'); }   any help is appreciated.

Is there a regular expression to validate an email address in JavaScript?


I have both Linux and Windows installed on my computer.  I want to set it up so that that every time I reboot my computer it automatically loads the other OS:    Linux-> (restart) --> Windows Windows-> (restart) --> Linux   How can I do that?

Consider the following dual-boot setup:   Grub is installed to /dev/sda /dev/sda1 is mounted as /boot /dev/sda6 is mounted as / Windows 10 is installed to /dev/sdb2   As it stands now, Grub selects Ubuntu by default when it boots and I can remotely login via SSH. It is also possible to select Windows when Grub starts and I can remotely login via RDP.  The problem is that I have no way of selecting which OS to boot when I am not physically present.   describes a method for having Grub automatically boot the last selected operating system. However, this will not work. If I select Windows, I have no way to remotely restart the PC and boot Ubuntu.  Is there a way to remotely control which OS boots?


Clearly it's not set theory, because set theory is built on first order logic, which is in a sense more fundamental as it comes first (you need first order logic to even state the axioms of ZFC)  And then comes the philosophical nightmare that I have been wrestling with for weeks. What comes before first order logic.   The question started when I began my quest on studying logic. It bothered me to a great extent that the books I read always assumed a knowledge of sets, natural numbers, functions, relations and in one of them, even cardinality! And to put the cherry on the cake, a few chapters later the books would go on to describe ZFC and building set theory, as if they had not been using sets casually for the past few chapters.  Here are the answers I have received so far   First-order logic does not require the use of set theory There are certain things that you have to accept as primitives and part of an accepted metalanguage, which are needed as a starting point to lay the foundations of mathematics It's turtles all the way down   Regarding the first one, I have literally seen books on logic use terms like a language is a set of symbols or even "sets of well formed formulas", particularly something like $\{\phi_1,\phi_2,\dots,\phi_n\}\vDash \psi$ so I really don't know where the first point is coming from.  Regarding the second point, this makes much more sense, except that it seems no one can tell me what are the things we take as primitive and part of "common sense". Do we start off with a "common sense" understanding of sets and then build logic? Is it the same for natural numbers, functions, countability etc.? Is that to say that the ultimate foundation of all of mathematics is Naive Set Theory and Naive Number Theory? That just sounds so... unsatisfying. How can math be consistent, if our metalanguage of English is not (we can form contradictions like "This statement is false"). Ok basically my main question for this part is what are the things that we take as accepted and  "common understanding" before we build mathematics. Like precisely what are they. Sets? Natural Numbers? (Is the domain of discourse in first order logic also a "common sense" term?)  The third one really grinds my gears because it just brushes the whole issue aside and doesn't explain it at all.  To sum up my question, as a foundation for mathematics, there are some things that we humans have to take as understood for us to draw a baseline. What precisely are these things and does a naive understanding of them in a metalanguage mean that mathematics is not as precise as it appears to be. Also as an aside, when we prove things about first order logic, do we do it in our imprecise metalanguage? I have seen logic proofs that use induction and I'm so confused because Number Theory is a much higher level thing than logic.

I am trying to understand what mathematics is really built up of. I thought mathematical logic was the foundation of everything. But from reading a book in mathematical logic, they use "="(equals-sign), functions and relations.  Now is the "=" taken as undefined? I have seen it been defined in terms of the identity relation.  But in order to talk about functions and relations you need set theory.  However,  seems to be a part of mathematical logic.  Does this mean that (naive) set theory comes before sentential and predicate logic? Is (naive)set-theory at the absolute bottom, where we can define relations and functions and the eqality relation. And then comes sentential logic, and then predicate logic?  I am a little confused because when I took an introductory course, we had a little logic before set-theory. But now I see in another book on introduction to proofs that set-theory is in a chapter before logic. So what is at the bottom/start of mathematics, logic or set theory?, or is it circular at the bottom?  Can this be how it is at the bottom?  naive set-theory $\rightarrow$ sentential logic $\rightarrow $ predicate logic $\rightarrow$ axiomatic set-theory(ZFC) $\rightarrow$ mathematics  (But the problem with this explanation is that it seems that some naive-set theory proofs use logic...)  (The arrows are of course not "logical" arrows.)  simple explanation of the problem:  a book on logic uses at the start: functions, relations, sets, ordered pairs, "="  a book on set theory uses at the start: logical deductions like this: "$B \subseteq A$", means every element in B is in A, so if $C \subseteq B, B \subseteq A$, a proof can be "since every element in C is in B, and every element in B is in A, every element of C is in A: $C \subseteq A$". But this is first order logic? ($(c \rightarrow b \wedge b \rightarrow a)\rightarrow (c\rightarrow a)$).  Hence, both started from each other?


i have a question  i try some function like     DIR=/path/tmp/      if [ -d "$DIR" ]; then     and     if [ -f "$DIR" ]; then    but only check /path/tmp this path  how can i do?

From a shell script, how do I check if a directory contains files?  Something similar to this  if [ -e /some/dir/* ]; then echo "huzzah"; fi;   but which works if the directory contains one or several files (the above one only works with exactly 0 or 1 files).


My computer is dual boot system, it's on two partitions. Windows 7 is installed on the C drive and Ubuntu-12.10 is installed on the D drive. Ubuntu was installed using wubi. I need to reinstall Windows 7, would like to know if it will affect the Ubuntu installation.

I've posted a question  that I have a 32bits windows 7 on a dual boot machine with ubuntu 10.04 upgraded to 11.04. From the responses I had from the questions, I decided to reinstall the windows 7 but this time a 64bits version.  I've install the grub on the first section of the HDD on which ubuntu is install, meaning the 2nd Drive.  I still want guidance before I proceed.  What would you suggest me as best way to achieve that without disturbing the boot loading.  thank you for reading this.


Let $A$ be a subset of $\Bbb{R}^2$ with the property that every continuous function $f:A\to\Bbb{R}$ has a maximum in $A$. I have to prove that $A$ is compact.  Is $A$ were a subset of $\Bbb{R}$ then we could take a function that is monotone over the components of $A$ and show that each of the components is closed and bounded hence proving $A$ to be compact. But couldn't generalize this idea to a subset of $\Bbb{R}^2$ that easily.

I need to prove that $K\subseteq \mathbb{R}^n$ is a compact space iff every continuous function  in $K$ is bounded.  One direction is obvious because of Weierstrass theorem. How can i prove the other direction? I tried to assume the opposite but it didn't work for me.  Thanks a lot.


newbie here,  probably a logical error so, I started with a set of codes without class and then I tried to redo it by using it with the same outcome, but now I keep getting a NullPointerException error on words[i].display(); what am I doing wrong in my codes? below are my before and after codes... thank you in advance for anyone who can help!  also, I tried doing it with a normal string or without loading an external file and it works fine! why do I get it when I start using a loadstrings is there any difference?  BEFORE:     String [] allWords;  int index = 0 ;  float x;  float y;    void setup () {  size (500,500); background (255); //background : white  String [] lines = loadStrings ("alice_just_text.txt"); //imports the  external file String text = join(lines, " "); //make into one long string allWords = splitTokens (text, ",.?!:-;:()03 "); //splits it by word  x = 100; //where they start  y = 150;   }   void draw() {  background (255);  for (int i = 0; i < 50; i++) {  //produces 50 words    x = x + random (-3,3); //makes the words move or shake   y = y + random (-3,3); //makes the words move or shake    int index = int(random(allWords.length));  //random selector of words    textSize (random(10,80)); //random font sizes   fill (0); //font color: black   textAlign (CENTER,CENTER);   text (allWords[index], x, y, width/2, height/2);    println(allWords[index]);    index++ ;    }  }   and the AFTER:  String [] allWords; word [] words; int index = 0 ;  void setup () {  size (500,500); background (255); //background : white textSize (random(10,80)); //random font size  String [] lines = loadStrings ("alice_just_text.txt");  String text = join(lines, " "); //make into one long string allWords = splitTokens (text, ",.?!:-;:()03 "); //splits it by word  }  void draw() {  background (255);  for (int i = 0; i < 50; i++) {  //produces 50 words   words[i].display();    }  } class word { float x; float y;   word(float x, float y) {   this.x = x;   this.y = y;  }  void move() {  x = 120 + random (-3,3); //variables sets random positions  y = 130 + random (-3,3); //variables sets random positions }  void display() {  int index = int(random(allWords.length));  fill (0); //font color: black  textAlign (CENTER,CENTER); //should make it start at the center  text (allWords[index], x, y, width/2, height/2); //positions     }     }

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


Let us assume $A,B\subseteq \Bbb R^+ $ are disjoint sets and $A\cup B=\Bbb R^+ $. Furthermore, $ \forall_{x,y\in A} \ x+y \in B \ \text{and}  \ \ \forall_ {x,y \in B} \ x+y \in A.$  Is it possible to provide an example for such $A$ and $B$?  If not, I would like to know why, and also prove the existence of such $A$, $B$ using Zorn's lemma. However, I couldn't figure out how to do it.  Please do not provide full proof as I am only looking for hints.

Let $\Bbb R^+$ be the set of positive real numbers. Use Zorn's Lemma to show that $\Bbb R^+$ is the union of two disjoint, non-empty subsets, each closed under addition.


I'm using Windows 8 and appreciate the ability to reorder my programs at will in the taskbar. However, for different windows of the same program - I have three Firefox windows, for instance - I can't seem to reorder them; what's worse, they seem to regularly switch themselves around for no reason I can see.  I usually want my main Firefox window to be the first (leftmost) one in the taskbar, with my work window second and the third window last, but every now and then they get mixed up and I have to get used to remembering which is which all over again, and I can't figure out how to manually fix them. I think this happens with programs other than Firefox too, but I suppose I could be misremembering.   Is there any way to reorder the taskbar buttons corresponding to multiple windows of the same program manually? Why does the order of my Firefox windows keep shifting around? Is there a way to ensure it keeps the order straight?

Is there a way to arrange windows within the same application in the taskbar of Windows 7?  Right now we can freely adjust each application's position in the taskbar, but within the app itself the windows can't be reordered, for example multiple windows of firefox or chrome.


The review queue home pages look pretty much the same across the Stack Exchange network. However, I noticed that on Stack Overflow the Close Votes and Reopen Votes review queues have an option to filter on the close reason (ordered by the most common one? I can't tell):  and the First Posts review queue on Super User has an option to filter on tag (only [windows-10] is shown, I suppose that's the most common tag):  Is there any (documented or not) logic when those options are shown? The post linked to by @rene mentions  Currently it's enabled only on Stack Overflow. Note, that we have a big threshold (50) for how many outstanding reviews there must be with a tag or close reason in order for it to show up on the dashboard. Update Jan 3rd, 2017: As noted below, this is implemented - however, it cannot be enabled for tags on Stack Overflow, as . Close reason filters from /review are still operational, and tags as well on smaller sites (currently Super User and Ask Ubuntu).  I assume that's still up-to-date, but the type/tag filters are only shown when you have access to the queues so I can't check. Still, it's close enough to what I was looking for.

Short version:   Make a filter selection page the default entry point for the review queues Show the size of the queues for tags they are likely able to work with - not the whole queue When all review options are done, show the user the impact they have had on the view of the queue they were given to start with     Long version:  There are (at least) two things that discourage people from getting into the /review - the appearance of an endless list that one can't make a dent on and having to 'skip' all the time to get to questions that one does know how.  I'll also point out that I suspect that some honest review audit failures come from people trying to review things they don't have a grasp of.  Making it easier for people to review what they do know may make it easier to honestly pass audits.  Under this model instead of showing someone trying to make a dent in "84,803 need review", break it down to the tags and reasons that a person can work with and see a reward from.  I'm going to use   for this because he has more interesting tags than I do.  I'm also going to pretend that everything he answered or asked is in the close review queue for the purposes of data.  Take the top 50 tags a person has.  This is about the first page of tags.  The reason for this is that it helps ensure that there is enough to build up a queue.  It also helps identify the questions that a person is likely able to cast the appropriate close vote (or leave open) on without guessing about technologies one is less familiar with.  Instead of clicking on the review and just getting at the queue with that little filter link at the top, one instead is taken to a filter selection page where one can build up the appropriate filter to work from.      You could select wedges from the pie chart, or select them from the list on the side.  Furthermore, there would also be a place to enter other tags.  Additionally, there would be a breakdown by close reason that one can select to build up the appropriate filter.  With both tags and close reasons, a question can fall into multiple spots.  For the purposes of this, show it in both tags or reasons.  Upon completing all the reviews for the day, show the information again, and allow them user to see the impact on the tags and reasons they chose.  This is the reward - not a badge or something, but a visible impact on the size of their corner of the queue.  One of the things this may help do - by presenting this information - is hep engage the various tag communities around the site to go and work on the review queue for their tag.  Seeing that some tag went from 3894 questions in the queue to 3563 in the last day may help.  Allowing a person to go and address just the off topic - recommend or off topic - migration (note, those are time sensitive) -- or even just 'off topic').  Of course there should still be a 'just take me to the queue' (and one can still set up the filter in the queue that way).  The key is to show the impact of what they have done to the queue in a way that is meaningful and not overwhelming.    A mockup to give an idea of what I'm thinking about.  Don't look too deeply into the numbers, they are more as an example.  You hit your standard 'review' link to get to the close review queue.  Instead of taking you right to the reviews, you get a page of stats that lets you see what is in the queue and modify the filter.    Note the 'Other' box at the bottom which has the same functionality as the 'tag' input that one can get from the current filter link.  I should also point out that the 'Review!' link can be clicked on without setting up any filters if you want to just "take me to the queue" and tackle whatever is there or use the old filter style setup.  You go through, you do your reviews and then you have a page that shows the queue once you've exhausted your tag or your reviews for the day.    Thats really what its about.  Make it easy to set up the filter of things you are likely able to review, make it easy to see what effect you have had on the queue when you are complete with the review.


I'm trying to print a PDF given to us at the University. The PDF writer has (unhelpfully) used a black background with white text, see an example image.    I've tried the Edit > Preference > Accessibility options in Adobe Reader to try and invert the colour of the background but without success. I was able to modify the text, but not the background. Even so, this changed all the text, not only white text, so its' not quite what I wanted anyway.  My printer options also didn't allow any inversions. I could screen-scrape each page and manually invert, but I was wondering if there is a more elegant / automated way to swap the background and text colours.  The related question  was asked over 3 years ago and no answer worked nor was accepted. Hopefully there is a solution now.

I have an existing PDF with a totally black background and all text is white.    Is there a way to get the text to print black and the black background to not print at all?  I have Bluebeam and Adobe PDF.


Given matrix $A\in M_{n}(\mathbb{C})$, if $\left<Ax,x\right>=0$ for all $x\in \mathbb{C^n}$, then $A=0_{n}$. (Here $\left<a,b\right> = b^{\ast}a$ where "*" is the conjugate transpose.)  Can anyone help me prove this? By Schur's theorem, A is similar to a strictly upper-triangular matrix, which is nilpotent. I'm not sure if this will help me.   ETA: In the comments I linked to an answer in which the author states "for $\lambda\neq 0$ we get $\left<Ax,y\right>=-\frac{\bar{\lambda}}{\lambda}\left<Ay,x\right>$. For fixed $x,y$ we can vary $\frac{\bar{\lambda}}{\lambda}$, so that $\left<Ax,y\right>=0$. Can someone help me understand that last statement, i.e. how we can get $\frac{\bar{\lambda}}{\lambda}$ to be $0$?

How to show that if $A, B \in M_{n}(\mathbb{C})$, and $x,y\in \mathbb{C}^{n}$ then the following two conditions are equivalent,   1.) $\langle Ax,y\rangle =\langle Bx,y\rangle$   2.) $\langle Ax,x \rangle= \langle Bx,x \rangle$   for all $x,y$?


In our SharePoint sites, we have a number of places where a user (SBS) can be inserted. For example, which user is responsible for a particular task. However, when selecting this user, there is a list of every single possible user to associate, including groups and even inactive users.  How can I restrict these user fields to only display and accept currently active user accounts?

I have my user profile synchronization setup and working but I have noticed that disabled users who no longer work for my company are showing up in the sync.  I would like to update the sync so that it only pulls in active users.


I have a small time series data with 10 observations Each observation is spaced at 20 days gap For example, I have sales revenue from day 1, day 21, day 41, day 61 till day 221... Now I would like to predict what will be the sales revenue on day 500th day amd 850th day? How can we predict using short timeseries data (which has only 10 observations)? Is there any specific technique that I should follow? Can you guide me on how would you guys do this? What are some of the topics that I should learn to do this? Can someone please help me with list of steps on how to do this?

I have a question related to modeling short time-series. It is not a question , but how. What method would you recommend for modeling (very) short time-series (say of length $T \leq 20$)? By "best" I mean here the most robust one, that is the least prone to errors due the fact of limited numbers of observations. With short series single observations could influence the forecast, so the method should provide a cautious estimate of errors and possible variability connected to the forecast. I am generally interested in univariate time-series but it would be also interesting to know about other methods.


Suppose I have a list of words and a tex-document. Now I want to color every occurrence of these words in the PDF created by pdftexify.  How to do that?

In order to revise a draft, and identify related sections, I would like to identify similar words (by color of text, highlight, underline, or otherwise) according to topic.   For example, I would like all uses of the terms "foo" or "bar" highlighted red and all uses of "biz" and "baz" highlighted green.  There might be four or five groups of words or word roots that I want to specify. This is only for revision, so it can be rather crude.  For example, replace this:    with this:    (In the example, it is hard to see the green text; perhaps bold+color or underline would be more useful)  Update A  provides an answer using XeLaTex. My document does not compile with XeLaTex, I would prefer a solution compatible with pdflatex if available (since that is what I use), though my document also compiles with luatex.  Other related questions:    (answer is not generic - requires seven lines per string to be replaced)  (only provides xelatex solution)   (uses chickenize, replaces string but does not add color)


With the axiom of choice this is trivial, but is there any way to construct this injection explicitly in the ZF system?

Why does a proof of $\exists f: X\to Y$ injection $\iff \exists g: Y \to X$ surjection requires the axiom of choice?  This question is answered here:   I'm not interested in a proof itself of this theorem, I want to know why this requires the Axiom of Choice.


I answered a question without creating an account I guess. This account was somehow created for me.  Then I registered the name, but a new account was created. So, can someone help me merge those two identities ?  and  Thank you.

I accidentally posted a question without being logged in. Is there a way to associate that question with my account?   For more information, visit "" in the .   a.k.a. How can you link a registered account to a cookie-based account? a.k.a. How do I merge an unregistered account with a registered account a.k.a. Merging users a.k.a. How do I associate anonymous questions I’ve asked with my registered account? a.k.a. Is there a way to claim an unregistered user? (in case anyone searches with those terms)