.NET says it supports 44 languages.for example i write the code in C# in execution time it converted in to IL and again coverted in to Machine language.is there any chance to get VB Code when iam compile the C# code. IS THERE ANY CHANCE

I am looking for a disassembler or better, a decompiler for .net.  The situation is that the source code for an assembly written by one of my predecessors is lost and I'd like to take a look to see what it's doing.  I know that ildasm comes with the Visual Studio installation so I can get at the MSIL, but I was hoping there was a program clever enough to work back to the C# code (or best approximation).  Are there any tools for this out there?  (If not, I suppose it'll be a good excuse for me to sit down and start to learn MSIL)


I have these two classes:  template <typename GeomType> class InputCSV { public:     InputCSV(DataSet<GeomType> * ds) : ds(ds) {}     virtual ~InputLoaderCSV() = default;      DataSet<GeomType> * ds; };   and  template <typename GeomType> struct DataSet {     template <typename LoaderType>     static DataSet<GeomType> Create()     {         DataSet<GeomType> ds;         ds.fileName = "something";         ds.input = std::make_shared<LoaderType<GeomType>>(&ds);         return std::move(ds);     };      DataSet(const DataSet & ds) = delete;      DataSet(DataSet && ds)     {         this->fileName = std::move(ds.fileName);         this->input = std::move(ds.input);         this->input->ds = this;          ds.input = nullptr;          }      std::string fileName;     std::shared_ptr<InputLoader<GeomType>> input;     protected:            DataSet() : input(nullptr) {} }   Now somewhere in code, I want to do  auto ds = DataSet<Line>::Create<InputCSV>();   where Line is some struct I have. However, this is not working and I got this error:  error C2672: 'DataSet<Line>::Create': no matching overloaded function found error C3206: 'DataSet<Line>::Create': invalid template argument for 'LoaderType', missing template argument list on class template 'InputLoaderCSV' note: see declaration of 'DataSet<Line>::Create'  error cannot access protected member declared in class 'DataSet<Line>' note: see declaration of 'DataSet<Line>::DataSet' note: see declaration of 'DataSet<Line>'   Is there any solution to have this kind of "syntax", or I have to write  auto ds = DataSet<Line>::Create<InputCSV<Line>>();   and change  ds.input = std::make_shared<LoaderType<GeomType>>(&ds);   to  ds.input = std::make_shared<LoaderType>(&ds);   In this example, I donw like "duplication" of  in InputCSV, since there cannot be anything else.

I've seen some examples of C++ using template template parameters (that is templates which take templates as parameters) to do policy-based class design. What other uses does this technique have?


Let $a$ and $b$ be some real numbers. Are there some constants $C>0$ and $p>0$ (where $C$ does not depend on $a$ or $b$) such that the following inequality holds? $$||a|^p-|b|^p|\le C|a-b|^p$$ I can show $|a|^p \le C |b|^p + C|a-b|^p$ but not exactly this one ?

If $a, b \in \mathbb{C}$, then we have the standard triangle inequality for the difference:  $$||a| - |b|| \le |a - b|.$$  I am wondering if this inequality generalizes to exponents greater that one.     My question is, for $1 < p < \infty$, does there exists a constant $C_p$ such that $||a|^p - |b|^p| \le C_p|a - b|^p$ for all $a, b \in \mathbb{C}$?   I am aware of the "standard" triangle inequality for $p > 1$:  $$|a +b|^p \le 2^{p}(|a|^p + |b|^p),$$  and that $2^p$ may not be sharpest constant possible. If I try to use this estimate to prove, say, that $|a|^p - |b|^p \le C_p |a - b|^p$, I get stuck with an extra term that I'm not sure what to do with.  $$|a|^p - |b|^p \le 2^p|a -b|^p + (2^p -1)|b|^p.$$  A resolution on this matter is greatly appreciated.


I'm new on photography, actually not new yet. I'm confused on which camera to choose for my first. There is up to 400$ in my packet for my first camera. I've searched alot and found two main dslr like cameras; Canon Sx50 hs and Sony HX300.   But then, I read some posts about high noise on higher iso levels on dslr like cameras such these two. Then I tried to find an entry level dslr camera but couldn't find, because I don't know about cameras. Could you please help me on this?

What  are the differences between a bridge camera and a DSLR?


My system is showing advertisements of all sorts popping everywhere and I cant use my system properly. Someone suggested it is a malware issue but what are my options how to detect which malware and how to cure it.

What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.


Why did the wampa put Luke Skywalker upside down in the ice cave on Hoth?

In Star Wars: Episode V: The Empire Strikes Back, Luke's attacked by a Wampa and knocked out.  When he awakens, he's dangling upside down, with his feet frozen into the ice on the ceiling.  How'd the Wampa manage this?  There's no indication that the Wampa is particularly intelligent, so how did an animal accomplish this feat of melting some of the ceiling, sticking Luke's feet in there, and letting it refreeze around his feet?


What is the difference between these two words in the following examples:   Why don't you get your hair cut? Why don't you have your hair cut?

Why do 'get' and 'have' work similarly in      I got/had my car repaired.    but differently – that is are not complemented in the same way although they still mean the same – in      I got someone to repair my car.    and      I had someone repair my car.


I have just started using LWC recently having normally coded front-ends in Angular of some sort. There are a couple of things that you don't seem to be able to do with LWC that seem to be really bloating my code, but I wondering if I'm just haven't come across the right way of doing things.  Objects can't be tracked  I'm used to getting a record from the server and assigning it to a single property in the component class, and then referring to a property of that object from the template, e.g.:  <my-component [some-attribute]="myModel.property"></my-component>   Whereas with LWCs, a separate tracked property needs to be created for each property of the model used on the template, and then transformed back into a single object on save etc. It seems very long-winded for scenarios with lots of properties.  There are no expressions  I've found that using template expressions in Angular is very handy way to cut down on code because a single property in the component class can be referenced in different ways, e.g.  <input name="account-name" [required]="stagePercentage >= 50" /> <input name="account-postcode [required]="stagePercentage >= 80" />   whereas for the same scenario with LWCs, two handler functions would have to be written in the controller:  <lightning-input required={stagePercentage50OrMore} /> <lightning-input required={stagePercentage80OrMore} />   and that is just a very simple scenario.  Have I missed any obvious patterns or ways of approaching this? Are there ways I could be reducing code here?  Thanks

How can expression functions similar to Visualforce and Lightning Aura Components be achieved within lightning web components?   For example, <template if:true={index % 5 == 0}>
</template> expression index % 5 == 0 is not compyling at all.  accountList.html  <template>     <template if:true={accounts.data}>         <template for:each={accounts.data} for:item='item' for:index='index'>                                       {item}         </template>     </template> </template>   accountList.js  import {LightningElement, wire} from 'lwc'; import getAccounts from '@salesforce/apex/TestController.getAccounts';  export default class AccountList extends LightningElement {      @wire(getAccounts) accounts;  }   Since LWC doesn't support Expression Functions, I'd like to know how to implement them.


I'm making a 2D top-down tile-based game in C++ using SDL2. The game uses a very large world map (think Dwarf Fortress).   My world terrain is generated using a noise function, another function is then used to build towns, model NPCs, etc. which are then saved to a local SQLite database (I'm using a database because NPC states, for example, are quite complicated - the database models their relationships with other NPCs, changing personalities, goals etc., and can be affected by player interactions with them as well).   At any point in time during play, the player is in some 'sector' of the world map. Currently, only interactions in the player's current sector are modeled (e.g. NPCs talking to each other, NPCs fighting each other etc.).  How can I model interactions across the entire world map, without the obvious computational problems of modelling every single interaction that occurs?   Is there some pattern which can generalise interactions?   The game uses time heavily (where a minute of game-time is a second in real-time, and thus in-game minutes, hours, days, months and years can be used). Could I somehow compute large-scale estimations of changes overtime? Some of these changes could be computed on player entry into the sector, based on how long it has been since the player has been in that sector (e.g. NPC getting older, dying of age etc.), but some changes should occur as they actually 'happen' (e.g. cross-sector things like an army or a trader travelling across the map).

I've been developing  for a little while now, but I've found that I want to make the game world MUCH bigger. It's currently about 300*300 tiles, but has creatures and bad guys running around the whole thing, so I've got to keep track of all the enemies movement and hostile-finding algorithms. I'm wondering how I can scale something like this up? It seems (from code profiling) that enemies are the limiting factor, and it's mainly that for each enemy, I need to scan through all the player-units and creatures to see if they're close enough for the enemies to see/attack. Edit: W,S,A,D,B,Q, if anyone's interested in controls :) Edit 2: Please tell me if there's any way I could improve the question!


How can I prove that $x^2-y^3=1$ has only one solution in the domain of $N^+$? Namely $x=3, y=2$. My try: $x^2-1=y^3  => (x-1)(x+1)-1=y^3$. $gcd(x-1,x+1)$ is 2 if $x$ is odd and $1$ if $x$ is even.  In the case x-even the only possible solution would be if $x=1$ but $y>0$. Therefore $x$ is odd.  Let $x=2p+1$. We can rewrite the equation as $4p(p+1)=y^3$.  $gcd(p,p+1)=1$, therefore $p(p+1)=2$. Therefore $x=3$.  Is that correct ?

The equation $y^2 = x^3 + k$ for $k = (4n-1)^3 - 4m^2$, with $m, n \in \mathbb{N}$ and no prime number that p is congruent to 1 modulo 4 divids m, doesn't have any answer and its proof can be obtained by using quadratic reciprocity law.  Do you know answers of this equation for two or three different values of $k$? In addition, do you know any reference about that?


I am having four mysql tables  Table 1, t_source:  +--------+-------+ | cindex | cname | +--------+-------+   Table 2, t_language:  +--------+-------+ | cindex | cname | +--------+-------+   Table 3, r_src_cat:  +-----------+-----------+-------+ | src_index | lan_index | clink | +-----------+-----------+-------+   Table 4, r_source:  +-----------+-----------+-------+ | src_index | lan_index | clink | +-----------+-----------+-------+   I want to retrieve clink, source and language indexes or name from table 3 - r_src_cat which are not present in table 4 - r_source. For this I am using following query:  SELECT   r_src_cat.clink,   t_source.cname,   t_language.cname FROM r_src_cat, r_source, t_source, t_language WHERE r_src_cat.c_src_index != r_source.c_src_index       AND r_src_cat.c_lan_index != r_source.c_lan_index       AND t_source.cindex = r_src_cat.c_src_index       AND t_language.cindex = r_src_cat.c_lan_index ORDER BY r_src_cat.clink;   This is giving me wrong results. There are about 12 records missing from r_source, but result is giving me like infinite number of any record displaying same record multiple times and that record is present in table.  Please rectify my query.  Thanks  EDIT---  Foreign Key Relations  Table 3, r_src_cat.src_index=>t_source.cindex Table 3, r_src_cat.lan_index=>t_language.cindex  Table 4, r_source.src_index=>t_source.cindex Table 4, r_source.lan_index=>t_language.cindex  EDIT 2----  By different suggestions, i run this query  SELECT   r_src_cat.c_src_index,   r_src_cat.c_lan_index FROM r_src_cat   LEFT JOIN r_source ON r_src_cat.c_src_index = r_source.c_src_index WHERE r_source.c_src_index IS NULL;   Result  352 0 352 0 352 0 352 0 352 0 352 0 352 0 352 0 352 0 352 0 352 0 338 0 338 0 569 0 569 0 569 0   This result is correct, but not complete. For e.g.,I run following query on table 3:  SELECT   r_src_cat.c_src_index,   r_src_cat.c_lan_index FROM r_src_cat WHERE r_src_cat.c_src_index = 535 AND r_src_cat.c_lan_index = 11;   It is showing a result set with one row.  Now the same query on table 4 - r_source:  SELECT   r_source.c_src_index,   r_source.c_lan_index FROM r_source WHERE r_source.c_src_index = 535 AND r_source.c_lan_index = 11;   It returns and empty return set.  So combination 535,11 is present in table-3, but not in table 4. But the same combination is not present in running the Left Join query on table 3 & 4 mentioned above.


When I try to include a pdf file in my appendices, it gives the header and the label, and begins the pdf-file on the next page. I have a lot of pdf-files as my appendices, many only 1 page long, meaning I will have a lot of blank pages only saying:   \usepackage{pdfpages} \begin{appendices} \section{Interviews} \subsection{Interview: Christine} \includepdf[pages=1-2]{fig/interviews/christine.pdf} \end{appendices}   This results in:     The rest of the page is then blank, and the actual appendix begins on the next page.   Is there any way I can alter the pdf-file to begin on the same page as the headline, maybe by scaling it to be smaller than actual page-sizes, so it fits on the same page?

I am using pdfpages which works quite well.  But this time, I want to include a 5 page pdf and the first page should be scaled down a bit such that above the first page is enough space for a subsection (in the LaTeX document).  Using just  \usepackage{pdfpages} ...  \subsection{Interesting Letter} \includepdf{letter.pdf}   does not work, because includepdf inserts a newpage command before the first page.  I looked at the pdfpages manual but could not find options relating to that.  I hacked this command, which kind of works:  \newcommand{\insertrep}[1]{% \hspace*{-2.4cm} \fbox{\includegraphics[page=1,scale=0.8]{#1}} \includepdf[scale=0.8,pages=2-,frame]{#1} }  \subsection{Interesting Letter} \insertrep{letter.pdf}   The subsection is printed on the same page as the first page of the pdf, but an empty page is inserted before the section ...  The empty page vanishes if I scale the first page to 0.5 - which is too small ...  It seems that \includegraphics inserts an empty page before the graphic, if the inserted graphic violates the margins of the page.  Besides, the hspace value does not always fit.  Thus, my question: How to solve this right?


I have a pseudo code from university:  (0) initialize logic array prim[ n ] (1) prim[ 1 ] = false (2) for i = 2 to n do (3)   for k = 2 to i − 1 do (4)     if i % k == 0 then (5)       break (6)     prim[i] = (k == i) // Was loop (3) fully executed? (7) return prim[]   Now I have to calculate the Big O for this pseudo code.  We learnt to make it step by step, by adding up the number of operations.  This is what I got so far:  Comparisons:  (4): (n-1)(n-2) outer loop * inner loop (6): (n-1) outer loop  (4) + (6): n^2 - 2 n + 1 operations for all comparisons   Assignments:  (1): 1 (6): (n - 1)  (1) + (6): n operations for all assignments   Division:  (4): (n-1)(n-2) outer loop * inner loop  n^2 - 3 n + 2 operations for the division.   So if you add up those numbers:  (n^2 - 2 n + 1) + n + n^2 - 3 n + 2 = 2n^2 - 4 n + 3   I think there is somewhere a misconception from my side, because the Big O should be O(n^2) but here it is O(2n^2) from what I understand.  Can you guys please help me figuring out, what my misconception is. Thanks

I'd prefer as little formal definition as possible and simple mathematics.


Let's say that I have a bag of unfair coins. Each coin $\mathit{i=1...N}$ has a probability $\mathit{p_i}$ of giving heads when tossed. If I toss each of my coins once and count the number of heads, what distribution (and parameters) will describe the number of heads I get? I know that if I used the same coin $\mathit{i}=I$ the probability mass function would be a binomial distribution $Pr(k;n,p_I) = \frac{n!}{k!(n-k)!}p_I^k(1-p)^{n-k}$ where $\mathit{n}$ describes the number of times I tossed the coin. In this case however I have $\mathit{n}$ different coins with $\mathit{p_1, p_2, ..., p_n}$ probability of heads tossed one time each.

Let $X_{i} \in \{0,1\}$ be Bernouli random variable with probability of success $p_{i}$, i.e., $P(X_{i}=1) = p_{i}$ and $P(X_{i}=0) = 1-p_{i}$ and let $Y=\sum_{i=1}^{n}X_{i}$ for $n>0$. Is it relatively simple to estimate the pmf $P(Y=y)$ when $p_{i} \neq p_{j}$ for $i \neq j$?


It is said that we should always use std::unique_ptr instead of std::auto_ptr and it is said that we were not able to store a auto_ptr in a container But consider this example:  int main(int argc, char* argv[]){      std::vector< std::auto_ptr<int> > v;     std::auto_ptr<int> u(new int(5));     v.push_back(u);     v.push_back(std::auto_ptr<int>(new int(10)));      typedef std::vector< std::auto_ptr<int> >::iterator v_ap_it;     for(v_ap_it beg = v.begin(), e = v.end(); beg != e; ++beg)         std::cout << **beg << " ";        std::cout << std::endl;     return 0; }   The program runs fine. I've tested it on vC++ 6.0 and it works fine but doesn't run on C++11 and C++14 ! So how could it be not possible to store it in a container?  * does this mean VC++ 6.0 is erroneous? I think so because it a buggy IDE.

Why is it wrong to use std::auto_ptr<> with standard containers?


Error output:  C2065 : 'Shape':undeclared identifier   |   file: Scene.h  I searched around for an hour and I can't seem to solve this basic error. I'm lost a this point. I'm sure It's something basic and I'm going to get -1 for it, but I really don't see the problem.  Scene.h  #pragma once  #include <vector> #include <memory> #include "Shape.h"  class Scene { protected:     std::vector<std::unique_ptr<Shape>> m_shape_ptrs; // <<<<< HERE     //std::vector<std::shared_ptr<Light>> m_light_ptrs;  public:       inline Shape& get_shape(int i) { return *m_shape_ptrs[i].get(); }     std::pair<Shape*, float> intersect(const Ray& ray) const; };   Shape.h  #pragma once  #include "Ray.h" #include "Vector.h" #include "Material.h"  class Shape { public:     Material material;      virtual float intersect(const Ray& ray) const = 0;     virtual Vec3f get_normal(const Vec3f& p) const = 0; };   Material.h  #pragma once  #include "bitmap.hpp" #include "Renderer.h" #include "Shape.h"  // <<< HERE IT IS A CIRCULAR DEPENDENCY #include "Ray.h"  class Material { public:     enum class TYPE : unsigned char     {         NULL_MATERIAL =  0,         MIRROR,         TRANSPARENT,         PHONG,         DIFFUSE     };      TYPE type;      rgb_t get_color(const Shape& shape, const Ray& incident, const Renderer& renderer) const; };

I often find myself in a situation where I am facing multiple compilation/linker errors in a C++ project due to some bad design decisions (made by someone else :) ) which lead to circular dependencies between C++ classes in different header files (can happen also in the same file). But fortunately(?) this doesn't happen often enough for me to remember the solution to this problem for the next time it happens again.  So for the purposes of easy recall in the future I am going to post a representative problem and a solution along with it. Better solutions are of-course welcome.     A.h  class B; class A {     int _val;     B *_b; public:      A(int val)         :_val(val)     {     }      void SetB(B *b)     {         _b = b;         _b->Print(); // COMPILER ERROR: C2027: use of undefined type 'B'     }      void Print()     {         cout<<"Type:A val="<<_val<<endl;     } };       B.h  #include "A.h" class B {     double _val;     A* _a; public:      B(double val)         :_val(val)     {     }      void SetA(A *a)     {         _a = a;         _a->Print();     }      void Print()     {         cout<<"Type:B val="<<_val<<endl;     } };       main.cpp  #include "B.h" #include <iostream>  int main(int argc, char* argv[]) {     A a(10);     B b(3.14);     a.Print();     a.SetB(&b);     b.Print();     b.SetA(&a);     return 0; }


Someone i barely know said he wants to move into my country and wants to borrow my account to transfer some cash as he does not want to bring cash in hands. Is it safe for me to give him my account number

I have a friend since July online and Exxon owe him for a balance on a 2014 contract off the shores of Liverpool. He is presently in the Gulf of Mexico completing a contract that last for one year. During that year he cannot get off the boat there fore he cannot receive the money.  Exxon has notified him that his check has been deposited in Samba Bank in London. If he doesn’t receive his money within two weeks it goes back to Exxon and he said that there I not telling nohow long before he will receive the money again. He said that with him being off shore that he needs me to be his beneficiary to receive the money for him. He wants me to keep the money in my account and when he gets off the boat in 6 weeks he is relocating to where I live.  I am to buy a house before he gets here and then he wants us to start a business together. He talked with me for quite a while before he told me how much he makes. He knows I do not have any money to mention. I have stock in a formal shop but not any money.  He said if this money had not come in when it did he would have had to postpone his plan until he gets paid what Shell Oil owes him for this contract that he will finish October 15th. He said he had given enough of his life to the gas and oil industry and is not going to sign another contract.  What do you think about the safety of this?


I'm having a hard time finding the because or since symbol in latex. alternatively is there a way to just flip \therefore in latex?

I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out?


I've looked into the  but can't find that there. Situation: from time to time, a wget query says for a public server name, there is a "Temporary failure in name resolution." After that it works again. What does this mean, exactly? And where to look for the problem source?  A verbose DNS query with more information about the protocol error? Logs of the DNS server?

Have read quite a lot of questions about this problem, but everyone just explain how to solve it (which do not work for me) and none what I have found actually explain what the reason for it is. Personally I get this problem with my home network All The Time! Literally about 20 times a day and every time it happens it can last up to 3 months if I am unlucky. My ISP say that it is a problem with my router, I have 2 routers now. One ASUS and one Linksys, the ASUS have default firmware and the Linksys have dd-wrt. I run 2 arch linux PCs and one Android smart phone. All devices get the same problem when it occurs. At the moment I use the Asus one because the Linksys never recovered while ASUS have internet access for about 5 min before loosing connection for about 10 min. Have borrowed a friends router and it is the same problem with that one. I can with all of them setup a LAN without any problem. Is this a problem on my end or over at my ISP? I would really appreciate an answer for this because when I call them they say that I am doing something wrong and are responsible for it, but I honestly think they are to blame. When the internet goes down compleatly I can still share the wifi from my phone and it works, so do not believe I have miss configured the wifi on my PC's.


In , it says     A not-null constraint is functionally equivalent to creating a check constraint CHECK (column_name IS NOT NULL), but in PostgreSQL creating an explicit not-null constraint is more efficient.   I'm wondering   What exactly does it mean by "more efficient"? What are the detriments of using CHECK (column_name IS NOT NULL) instead of SET NOT NULL?   I want to be able add a NOT VALID CHECK constraint and validate it separately (so the AccessExclusiveLock is only held for a short period of time for the adding of the constraint and then a ShareUpdateExclusiveLock is held for the longer validation step):  ALTER TABLE table_name   ADD CONSTRAINT column_constraint   CHECK (column_name IS NOT NULL)   NOT VALID; ALTER TABLE table_name   VALIDATE CONSTRAINT column_constraint;   Instead of:  ALTER TABLE table_name   ALTER COLUMN column_name   SET NOT NULL;

Trying to add a NOT NULL constraint to a table with 1 billion rows. I cannot afford a table lock for more than a couple of seconds. Is there a way to prevent a full table scan during the alter table statement? I created an index on the column hoping it would be used but that doesn't seem to work. May be a check constraint? Other options? Thank you!


Got a faster internet today so decided to test it and ... figured out that I have the same 20-30 Mbps out of 50, when wired.   I tried to play with channels, as I found that there are multiple neighbors running wifi on the same channel. It didn't give any significant and stable result. It could even drop below numbers I mentioned.   I tried to use a router from a provider and also attached another router to it. Both show the same performance. I tried also to play with modes and leave only 802.11n without any significant result either.   EDIT1: Here is a link to the wireless-info output   EDIT2: Tried to disable 11n, speed dropped 2 times, so didn't help. Didn't notice if swcrypto gives any drawbacks/benefits. I also noticed that Cisco router in 11n only mode works 50% faster and gives me about 30Mbps  ##### lspci ############################# 01:00.0 Network controller [0280]: Intel Corporation Centrino Wireless-N  2230 [8086:0887] (rev c4)     Subsystem: Intel Corporation Centrino Wireless-N 2230 BGN [8086:4062]     Kernel driver in use: iwlwifi  wlp1s0    IEEE 802.11  ESSID:"F62Q7"         Mode:Managed  Frequency:2.437 GHz  Access Point: <MAC 'F62Q7' [AC1]>          Bit Rate=43.3 Mb/s   Tx-Power=16 dBm          Retry short limit:7   RTS thr:off   Fragment thr:off       Power Management:on       Link Quality=65/70  Signal level=-45 dBm         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0       Tx excessive retries:1  Invalid misc:237   Missed beacon:0   So, the question is - if it's possible to achieve higher speed than the current one?

I have looked through all the previous questions but turning power management off for the Wi-Fi card didn't work. This problem seems to be with the Lenovo Thinkpads. I switched to Ubuntu 11.10 from Windows 7 3 days ago so I'm new to the operating system.


Please, does anyone knows whether $\operatorname{tr} |AB| = \operatorname{tr} |BA|$ for general trace operators $A$ and $B$ in Hilbert spaces ? Do you have a counter-example or a proof ?  Thanks  ps : I know $\operatorname{tr} AB = \operatorname{tr} BA$

there is a similar thread here , but I'm only looking for a simple linear algebra proof.


I need execute un update statement over an sql server table, this table is used by another process at the same time. because that sometimes deadlocks ocurs. wich Isolation Level do you recomend for L1 and L2 to avoid deadlocks?  p1:   set transaction level L1     delete from t1 where id=2     select * from t1 where id=3   p1:   set transaction level L2     delete from t1 where id=3     select * from t1 where id=2

I have a long running transaction (called, say, T1) that performs some deletes, updates and inserts on a table in SQL Server 2008 R2. At the same time, another process periodically runs select statements from this table.   Under default isolation settings (READ COMMITTED I think?), T1 blocks any select statements from running until the transaction commits or is rolled back.   What I'd like to see is for the select statements to function on consistent data even while the transaction is underway. I believe SNAPSHOT isolation can help, but am not sure if I'm going in the right direction. Would this be the best isolation level for this application?  Secondly, I don't have any control over the process that is calling the select statements, but I do have control over the .NET application that calls T1. Would any isolation level changes be required on both the select statements and T1, or would it be sufficient to mark  just T1 as having a different isolation level?


Let $a$, $b$ and $c$ be three distinct integers and $P$ a polynomial with integer coefficients. Show that the conditions $P(a)=b, P(b)=c$ and $P(c)=a$ cannot be satisfied simultaneously.  Using polynomial remainder theorem:   Remainder of the division of a polynomial $P(a)$ by a polynomial $a-b$ is equal to $P(b)$. Remainder of the division of a polynomial $P(b)$ by a polynomial $b-c$ is equal to $P(c)$. Remainder of the division of a polynomial $P(c)$ by a polynomial $c-a$ is equal to $P(a)$.   I can't find example where $P(a)=b,P(b)=c,P(c)=a$.  How to prove this contradiction?

While studying polynomials a question struck in my mind that  To have a polynomial $p(x)$ with integer coefficients and $a,b,c$ are three distinct integers, then is it possible to have $$p(a)=b$$$$p(b)=c$$$$p(c)=a$$


I have a Tier 4 Student Visa for the UK and am an Indonesian national studying in NYU London for 6 months.    What will I need to ensure and provide to make sure I get the multiple entry visa as well as anything I should do to increase my chances?     I'm planning on applying through the Czech embassy in London as it will be my point of entry and the country I'll be spending most of my time in for the Schengen area.

While applying for a Schengen visa, an option is given to choose between a single entry visa or a multiple entry visa. There isn't any published policy on this, but if it's the first time time I'm applying for a Schengen visa does it hurt my chance of getting one in case I say I want to get a multiple entry visa instead of single entry?  (By 'hurt' I mean say I ask for multiple entry and a stricter rule is used for checking whether the visa is granted, then will I be given a single entry visa instead or will the whole application be rejected?)


Let $p,q$ be primes, $p≠q$, then I have to show that $\mathbb{Q}(\sqrt{p},\sqrt[3]{q})= \mathbb{Q}(\sqrt{p}\cdot \sqrt[3]{q})$  So far I've tried a lot of things with minimal polynomials and bases, but I'm far from any argument that I find sufficient.  This is an example from my algebra course, first chapter about field extension. So far we know about basic definitions, minimal polynomials and their properties, algebraic elements and algebraic fields.  Could someone maybe give me a hint about how to proceed? Thanks a lot!!!

Can someone please give me a tip how to show that for distinct prime $p,q$ that $\mathbb{Q}(\sqrt{p},\sqrt[3]{q})=\mathbb{Q}(\sqrt{p}\sqrt[3]{q})$ and how to find the minimal polynomial of $\sqrt{p}\sqrt[3]{q}$ over $\mathbb{Q}$ ?


I'm just trying to vertically align the image and the text so that the text is between the top and bottom side of the image ( the image's height is bigger than the text's ) but applying margin/padding to the
 class does nothing.    .navUsernameP {   display: inline;   color: #fff;   text-align: center;   text-decoration: none;   white-space: nowrap;   margin-bottom: 10px; }  .navUsernameLi {   float: right;   margin-top: 10px; }  .navProfilePicture {   display: inline;   border-radius: 50px;   vertical-align: inherit;   height: 24px;   width: 24px; }

Username

Why won't vertical-align: middle work?  And yet, vertical-align: top does work.   span{   vertical-align: middle; }
      Doesn't work.


I was wondering  how the effect in the included images is achieved, I have noticed it is a popular technique used in website banners and 'hero' images.  I am interested in specifically what adjustments might be helpful to achieve this. ie the muted colors, suppressed highlights and faded blacks. Another characteristic of this image (other than the 'bokeh' lens effect) that interests me is the 'hazy', 'soft light' feel to it. It appears the light is contouring and pouring over the edges of the subject(s) of the photograph.  Any thoughts and tips would be a huge help, regarding what the general workflow might be to achieve this.  Many Thanks for your time and help.  Reference Image

I would like to use the overlay effect used on the screenshot(s) below.    I've tried experimenting with several Blending modes but keep missing the mark. I'm sure this has a very easy answer but I'm having trouble recreating the effect on my own.  Here are a few more images for further context:        Thanks in advance for your help.


I'm getting the errors attached as screenshots above when I try to start the virtual machine so that it installs windows 8. When the first error popped out, I clicked on continue and it brought the windows 8 logo for 3 minutes then it showed the black screen with the second error. I have also tried it with Physical Address Extension disabled and it brings the Windows 8 Recovery error. The host machine is a 4GB ram Intel Core 2 Duo CPU T6570 @ 2.10GHz × 2 and the Virtual machine has 1GB with 1 CPU. How do i get this virtual win8 machine to work?

I am running on a dual core AMD E450 CPU. When I tried to run a 64-bit OS that requires hardware virtualization using VirtualBox, it showed me an error message that "AMD-V is not enabled".    My AMD processor is supposed provide AMD-V support, but I can find no option for enabling AMD-V in BIOS.    How can I solve this problem? How can I enable AMD-V for my CPU?  Thanks in advance  lscpu :-  Architecture:          x86_64 CPU op-mode(s):        32-bit, 64-bit Byte Order:            Little Endian CPU(s):                2 On-line CPU(s) list:   0,1 Thread(s) per core:    1 Core(s) per socket:    2 Socket(s):             1 NUMA node(s):          1 Vendor ID:             AuthenticAMD CPU family:            20 Model:                 2 Stepping:              0 CPU MHz:               1650.000 BogoMIPS:              3291.72 Virtualization:        AMD-V L1d cache:             32K L1i cache:             32K L2 cache:              512K NUMA node0 CPU(s):     0,1   EDITED:-  Error message from VirtualBox:-  Failed to open a session for the virtual machine XXX.  AMD-V is disabled in the BIOS. (VERR_SVM_DISABLED).  Result Code: NS_ERROR_FAILURE (0x80004005) Component: Console Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}


I want to start and stop an external program in Python3, on Linux. This program is an executable, called smip-tun,  located in the same folder as the source code and I'd like to be able to execute and control it from there with relative names.  Unfortunately, this does not work:  smip_tun = 0  def start_smip_tun(self):     smip_tun =  subprocess.Popen(['smip-tun',DEFAULT_SERIAL_PORT])  def end_smip_tun(self):     smip_tun.terminate()     print("end")   But says it cannot find smip-tun. Efforts to specify the relative directory have failed. I was trying with cwd but cannot figure it out. Any advice?  Edit:   Made Smip-tun global but the issue persists.  New code:  smip_tun = 0  def start_smip_tun(self):     global smip_tun     smip_tun =  subprocess.Popen(['smip-tun',DEFAULT_SERIAL_PORT])  def end_smip_tun(self):     global smip_tun     smip_tun.terminate()     print("end")   Error message:    File "/home/sven/git/cerberos_manager/iot_network_api.py", line 40, in start_smip_tun     smip_tun = subprocess.Popen(['smip-tun',DEFAULT_SERIAL_PORT])   File "/usr/lib/python3.5/subprocess.py", line 947, in __init__     restore_signals, start_new_session)   File "/usr/lib/python3.5/subprocess.py", line 1551, in _execute_child     raise child_exception_type(errno_num, err_msg) FileNotFoundError: [Errno 2] No such file or directory: 'smip-tun'

How can I create or use a global variable in a function?  If I create a global variable in one function, how can I use that global variable in another function? Do I need to store the global variable in a local variable of the function which needs its access?


Why don't I have this option?    here's my disk layout  sudo fdisk -l  Disk /dev/sda: 640.1 GB, 640135028736 bytes 255 heads, 63 sectors/track, 77825 cylinders, total 1250263728 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x5b53cc54     Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048      409599      203776    7  HPFS/NTFS/exFAT /dev/sda2          409600  1153767021   576678711    7  HPFS/NTFS/exFAT /dev/sda3      1216962560  1250050047    16543744    7  HPFS/NTFS/exFAT /dev/sda4      1250050048  1250261679      105816    c  W95 FAT32 (LBA)  Disk /dev/sdb: 4005 MB, 4005527552 bytes 32 heads, 63 sectors/track, 3880 cylinders, total 7823296 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x20d8782d     Device Boot      Start         End      Blocks   Id  System /dev/sdb1   *          63     7822079     3911008+   c  W95 FAT32 (LBA)

Any of the partitions makes in Windows was not recognised by Ubuntu, or Zorin OS, or LinuxMint. It's like a blank hard disc, 250 gb free. I'm a new Linux user, but what confuses me is that I was able to install Ubuntu alongside Windows on my laptop with no problems, but on PC... no way!


I need to prove the limit of: $$\lim_{n\to\infty}\frac{1}{\sqrt[n]{n!}}=0 $$  I have tried bounding it by a pairwise bigger sequence but I cannot find one that is suitable. I also cannot figure out an $\epsilon$-proof, since I don't know how to adequately handle the factorial to get a substitution for n such that the convergence criterion is fulfilled.

I used $$(n!)^{\frac{1}{n}}=e^{\frac{1}{n}\ln(n!)}=e^{\lim\limits_{n\to\infty}\frac{1}{n}\ln(n!)}$$ Then using Stirling's approximation and L'Hospital's rule on $$\lim\limits_{n\to\infty}\frac{\ln(n!)}{n}$$ I get $$\lim\limits_{n\to\infty}\frac{\ln(n!)}{n}=\lim\limits_{n\to\infty}(\ln(n)+\frac{n+\frac{1}{2}}{n}-1)=\infty$$ Now, $$e^{\lim\limits_{n\to\infty}\frac{1}{n}\ln(n!)}=e^{\infty}=\infty$$ Thus $$\lim\limits_{n\to\infty}\frac{1}{\sqrt[n]n}=\frac{1}{\infty}=0$$  Is this correct approach and what other methods could be used?


So by using ssh you will connect to a server by typing in ssh User@PrivateIP how would it be possible to turn that code into a piece of code that works like a VPN (so searching for example google from a different geolocation). FYI: By connecting I mean that you connect to a computer of your own and not a supplied VPN server.

I have a laptop running Ubuntu.  I also rent a VPS running Ubuntu.  I've bought a paid VPN-service, which I use on my laptop.  I was wondering how I can set-up a SSH-tunnel or something similar, from my laptop to the VPS I'm renting, so I then can run VPN (from my laptop) "through" it (to the VPS), to the VPN-server.  The reason I wish to do so, is that a place I often work blocks my VPN-service, but not my SSHing to my VPS...  While I have been using Linux for a while, I'm a novice when it comes to setting-up virtual network-devices, advanced routing, and so on... so please spoonfeed me (using small words and colorful pictures ;-)  I have been googling and looking at various answers on the StackExchange-network, but not seems to be exactly what I'm after.  SSH-tunneling seemed promising, but since I don't have/know an exact domain and port for my VPN, I couldn't figure out how to use it...  I guess I may need to set-up some virtual network-device on my laptop (which ends on the VPS), and connect VPN through it - but how to do this, sadly goes over my head.


I recently was convinced of the benefit of using align over eqnarray, but I am really not writing \begin{align} ... \end{align}  every time, so I just did what I always do: \def\bea{\begin{align*}} \def\eea{\end{align*}}  However, align do not seem to work with my defined commands. I even tried other ways of defining, with \let and \newcommand, but none seem to work. I always get the same error. To give an example, if I type: \bea     E = mc^2 \eea  which is very simple, I still get:  Runaway argument? E &= mc^2 \eea ! Paragraph ended before \align* was complete.  \par  However if I write the full commands, it does work. How can it be so and how do I solve it? I know LaTeX only expands \eea into \end{align*}, so there should be no way one can result in error and the error cannot.

I'm trying to define two commands \bal and \eal instead of inserting \begin{align} and \end{align} in my document, but in the code below, I'll get some errors. What is wrong with it?    \documentclass{article} \usepackage{amsmath} \makeatletter  \newcommand{\bal}{%  \begingroup  \align% \@ifstar{\nonumber}{}%  }  \newcommand{\eal}{\endalign\endgroup} \makeatother \begin{document} \bal* x=y \eal \end{document}


I wonder whether anyone can help me please?  I am a private individual and have been using Ubuntu for many, many years and am now 76 years old.  I have no programming experience at all but I can following instructions if they are clear enough for an amateur to understand and apply.  During the years using Ubuntu I have not experienced any problems until now. I am using Ubuntu 16.04 64 bit. I was using the computer a couple of weeks ago and a Security Update flagged up and as usual I installed it.    When restarting the computer later that day it loaded showing only my desktop but without ‘sidebars’ and the cursor was a black ‘X’. I was unable to move or exit from the desktop without switching off the computer. Right clicking the mouse showed a number of options but nothing to enable me to exit.  I restarted and an error message popped up;- Executable Path  /usr/lib/x86_64 linux-gnu/unity/compiz-config-profile-setter. Package Unity 7.4.5 +16.04.2017..    I was able to re-start in ‘Recovery Mode’ and the desktop appears I believe with all the relevant items that were there before, but the screen is elongated from left to right.  I shall be grateful for any assistance you can give to enable me to correct this situation and would like to express my thanks in advance for your help.  Best wishes,   Godfrey Dingley-Jones

This  forced removal of unity and ubuntu-desktop on my 16.04 Ubuntu system.   The offending package that is missing, but unity needs, seems to be compiz-core-abiversion-20151010. It seems to be a , and I can't find it to download.    As it happens, I mostly use LXDE on this system, but I'd be very unhappy if I used Unity...  Since I do occasionally use the Unity desktop, is there a fix for this?  Edit: related questions are rolling in. Looks like a major quality escape          Edit 2:


Let $D=\{z \in \mathbb{C}: |z|<1\}$, then which of the following are true?   There exists a holomorphic function $f:D\to D$ with $f(0)=0$ and $f'(0)=2$. There exists a holomorphic function $f:D\to D$ with $f(3/4)=3/4$ and $f'(2/3)=3/4$. There exists a holomorphic function $f:D\to D$ with $f(3/4)=-3/4$ and $f'(3/4)=-3/4$. There exists a holomorphic function $f:D\to D$ with $f(1/2)=-1/2$ and $f'(1/4)=1$.   Now for option $1$, I see that it is not true by Schwarz lemma. But I don't know how to decide the rest. Schwarz lemma says one more thing that if $|f(z)|=|z|$ then $f(z)=az$ where $|a|=1$. So $|f(3/4)|=|-3/4|=3/4$, is this going to help? How can I proceed further? Help needed please.     Edit: Ok I just found that this is a duplicate of , but I still appreciate some answers as I didn't properly understand the answer given.

Let, $D=\{z\in \mathbb C:|z|<1\}$. Which are correct?   there exists a holomorphic function $f:D \to D$ with $f(0)=0$ & $f'(0)=2$. there exists a holomorphic function $f:D \to D$ with $f\left(\dfrac{3}{4}\right)=\dfrac{3}{4}$ & $f'\left(\dfrac{2}{3}\right)=\dfrac{3}{4}$. there exists a holomorphic function $f:D \to D$ with $f\left(\dfrac{3}{4}\right)=-\dfrac{3}{4}$ & $f'\left(\dfrac{3}{4}\right)=-\dfrac{3}{4}$ there exists a holomorphic function $f:D \to D$ with $f\left(\dfrac{1}{2}\right)=-\dfrac{1}{2}$ & $f'\left(\dfrac{1}{4}\right)=1$.   With the help of Schwarz lemma & its applications, we find that $(1)$ is false & $(3)$ is true.  But, I can not think about options $(2)$ & $(4)$.


Consider a continuous function $f$ over an interval $[a,b]$. Let $S$ be the set of all values that $f(x)$ takes over $I$. Intuitively speaking, I believe this set has a maximal and minimal value. Is this the case? How can I prove it?

As the title indicates, I'd like to prove the following:     If $f:\mathbb R\to\mathbb R$ is a continuous function on $[a,b]$, then $f$ attains its maximum.   Now, I do have a working proof: $[a,b]$ is a connected, compact space, which means that because $f$ is continuous, $f([a,b])$ is compact and connected as well.  Therefore, $f([a,b])$ is a closed interval, which means it has both a minimum and, as desired, a maximum.  What I would like, however, is a proof that doesn't require such general or sophisticated framework.  In particular, I'd like to know if there's a proof that is understandable to somebody beginning calculus, one that (at the very least) doesn't invoke compactness.  Any comments, hints, or solutions are welcome and apreciated.


When travelling on an Australian travel document for refugees, do I need a visa to enter South Africa?

Do I need a visa to travel to South Africa with a Germany refugee travel document? If yes, what is the requirement for the visa application at the South African embassy?


Up until Facebook closed it's doors on 'Public Post Search' I used to run a site that allowed for this function. Right now am building a new site and have a landing page that allows for the visitor (old or new) to sign up to be notified when the new site is up and running. This is done via email. Unfortunately I have suffered some people inputting non email addresses so solved that with a PHP function, however more recently I've started suffering from what are clearly not valid email addresses like 'foo@bar.com' etc...  Is there a recommended PHP function to check whether the email address is fully valid? If not, is there a free service which has an API that I could use to check whether the address is valid?

I have come across this .  Has anyone tried anything similar or does it work for you? Can you tell if an email customer / user enters is correct & exists?


I had upgraded to 20.04 from 18.04 without noticeable problems, but after that I found out that GNOME Shell don't display any application, viz. screenshot  If I type any name of installed application in the Search Bar, it will search that indefinitely. PC parameters: Dell Latitude E7450, Intel® Core™ i5-5300U CPU @ 2.30GHz × 4; Mesa Intel® HD Graphics 5500 (BDW GT2)

I did an upgrade today to the latest version of ubuntu. Everything looked good and fine only for me to discover that I cannot find my applications after clicking the 'Show Applications' icon. The same applies when I search for an application in the search bar, I do not see it. It shows me an endless search.  These are the screenshot images of the problem:      In the meantime, I access my applications from the menu at the top bar and also use the terminal to run applications with CLI.


How can I have a question unmarked as a duplicate?  I have had two questions now which have been incorrectly marked as a duplicate. I have explained clearly in my response why they are different, especially where the so-called duplicate question hasn’t been successfully answered, and the responses are dated.  I think that incorrectly marking a question as a duplicate devalues the process, and makes it difficult to move the question forward.  What is the mechanism for fixing this? The message says “please edit this question”, but that doesn’t seem to help.

I asked a question regarding a very specific feature of a program and whether or not it works with a larger program.  Within hours someone had marked it with "This question may already have an answer here of a similar question, but not related to my question.  The question I asked IS NOT ADDRESSED in the referred-to question. It's frustrating to spend half an hour putting together an intelligent and specific question, and then have someone mark it as a duplicate (or possible duplicate), which apparently causes people to skip over my question. I haven't received any more responses since the question was flagged.   Two questions:  (1) How do I get this flagging removed and (2) what's the best way to prevent these "helpful" flaggings in the future?


I have a question about prime order group.  answer by amWhy says that:      It follows that any group of order 5 (and any group of prime order) must be generated by a single element and is hence, cyclic.    I understand previous part but this. If any group of prime order must be generated by a single element??

Show that every group of prime order is cyclic.   I was given this problem for homework and I am not sure where to start. I know a solution using Lagrange's theorem, but we have not proven Lagrange's theorem yet, actually our teacher hasn't even mentioned it, so I am guessing there must be another solution. The only thing I could think of was showing that a group of prime order $p$ is isomorphic to $\mathbb{Z}/p\mathbb{Z}$. Would this work?    Any guidance would be appreciated.


ive downloaded the latest ubuntu iso file and copied it to my usb stick. i'm trying to boot from the USB stick on an aspire one net book and its telling me that its missing the operating system.

I am looking at this:    I need to create a boot disk to test Ubuntu to make sure it will run on a PC (Compaq Mini CQ10-120LA) I was given. I can create the boot disk off of a Mac (in English) or Windows (but Windows is in Spanish and foreign to me).   Questions:     What format do I choose for the USB stick? (I wish the instructions stated this). What is Dash? (Will I know when I run the installer?) Can I do this from a Mac or Windows computer? Or only from Ubuntu?


Question: $1.$ Let $m_1<m_2<\cdots<m_k$ be positive integers such that $\frac{1}{m_1},\frac{1}{m_2},\cdots,\frac{1}{m_k}$ are in arithmetic progression. Then prove that $k<m_1+2$. $2.$ For any $k>0$, give an example of a sequence of $k$ positive integers whose reciprocals are in arithmetic progression.  I have tried to solve the problem in many ways, but haven't been able to reach to anything significant. Can someone help?

Let $m_1,m_2,\ldots,m_k$ be $k$ positive integers such that their reciprocals are in AP. Show that $k<m_1+2$. Also find such a sequence.     Whatever way I tried, whichever formula I used, I could not eliminate the $m_k$ term, which I reckon would be the ideal scenario to find the solution. I am exhausted of any further ideas, please help. Thank you.


In one of my computers I  installed ubuntu 14.04. Actually , I tried to dual-boot in along with windows 7 and I tried to do the partition during the ubuntu installation procedure.   Now all of my 500 GB hard disk has been occupied by ubuntu and I cannot access windows. Since, I have all my documents in windows and I want to recover it. Will I be able to recovery my files of windows ? If yes, can you please help me with the solution ?

I have a Toshiba satellite A-200 laptop with a Vista OS on it with 4 NTFS partitions  (C:) Vista  (D:) Entertainment  (E:) Work  (F:) Sources   and I wanted to start using Ubuntu instead. So I tried it first from the live CD and everything was OK and all the partitions were shown and working and so I decided to install Ubuntu to replace Vista on the (C:) drive. After I did that I can no longer find my folders and files on the (D:), (E:), (F:) partitions and the only file system that is shown is one 198 GB although my HDD is 320 GB.  I can't access the lost data on the remaining 120 GB which I hope is still there and not totally lost  I am now working from the live CD but I am unable to install testdisk. Can I recover the Vista partitions by the product recovery CD to get my laptop back to the factory settings? Can I recover the NTFS partitions using a recovery program for Windows or will that make the problem worse?   I need these data badly as I don't have a backup for them.


I have the following rule in my .htaccess file:  # 1 Month for most static assets <filesMatch ".(css|jpg|jpeg|png|gif|js|ico|woff)$"> Header set Cache-Control "max-age=2592000, public" </filesMatch>   And I have but when I check my page on Google page insights I still see that one .js file has not been cached , the file the following file:  http://www.google-analytics.com/analytics.js (2 hours)   Now how exactly do I cache this file? How do I cache a Google analytics file?

I'm trying Google's PageSpeed online service  Ironically, it's primarily highlighting Google's own services as something that needs improvement on my site  1) jQuery from Google: blocking. So I moved all javascript from <head> to the end of the document before </body>. That helped  2) Linking to external Google Font CSS (in <head>): blocking. But the font is critical to the design of the page and should load before much else  3) Google Analytics: Caching is not good. (Google has set it internally to 2 hours expiration). Don't know how to change this (this is also placed at the bottom of page)  The Google Font is highlighted as a big priority to change.  How can I fix this? Where/how should I call the the font?


Is it possible to find out when the first version of an app was issued?  Google Play only shows the date of the latest update in ADDITIONAL INFORMATION field (see picture).    Ideally, I'd like to see when all the updates were issued. Probably, that's too much.

When you are viewing an app in Google Play store, it displays the following : Updated, Size, Installs, Current Version, Requires Android, and Rating.  I am trying to do some research and figure out the initial release / publish dates of different apps. Is there a way to get this information from Google Play, or perhaps a website with this information?


After SQL Server 2016 (SP1-CU3) patching we are not able to open the user database properties. Whenever its opened am getting below error:     Method not found: System.collections.specialized.stringCollection   Microsoft.sqlserver.management.smo.server.getpropertynames(System.type)'.   (SqlManagerUI)

I'm using SQL Server Management Studio 2016. When I try to create a local database by right clicking on Databases and selecting "New Database" I get the following error:    I've tried restarting SSMS and the machine.  I can create the database through SQL, however I get the same error when trying to launch any GUI dialogs for the database. So creating it thru SQL doesn't work around my issue as I need to configure it also (and I don't want to write scripts for everything).


Should the name of theories be capitalized? Does this depend on convention, the particular theory itself, or whether or not it contains a proper name?   I appreciate any input, thank you!

This is my first post and as you can probably guess I am a mathematician so I have no clue about grammar. I am writing a mathematical document at the moment and I would appreciate some advice on my usage of capital letters. Can somebody please confirm if the following are correct?  1) "We know by Theorem 4.6.1 that..."   2) "the following conjecture, due to..."  3) In order to prove the "Mckay-Stevens $k$-covering Conjecture, once needs to show that..."  I'm particularly confused about 3).  Many thanks for any help


I have a function to read in a tab delimited file which puts each column in a list and returns a list of lists with all the values from the column. This works fine for my small test file that I used with 1 column and 1850 rows, but I am now trying it with ~30k columns and it has been running for a few hours and still not finished.   How can I modify the code below to do this faster? If reading in a file if 30k rows with 1850 columns is faster i can also transpose the input files.  public static List<List<String>> readTabDelimited(String filepath) {     List<List<String>> allColumns = new ArrayList<List<String>>();     try {         BufferedReader buf = new BufferedReader(new FileReader(filepath));         String lineJustFetched = null;         for (;;) {             lineJustFetched = buf.readLine();             if (lineJustFetched == null) {                 break;             }             lineJustFetched = lineJustFetched.replace("\n", "").replace("\r", "");             for (int i = 0; i < lineJustFetched.split("\t").length; i++) {                 try {                     allColumns.get(i).add(lineJustFetched.split("\t")[i]);                 } catch (IndexOutOfBoundsException e) {                     List<String> newColumn = new ArrayList<String>();                     newColumn.add(lineJustFetched.split("\t")[i]);                     allColumns.add(newColumn);                 }             }         }         buf.close();     } catch (Exception e) {         e.printStackTrace();     }     return allColumns; }

Can anyone recommend a simple API that will allow me to use read a CSV input file, do some simple transformations, and then write it.  A quick google has found  which looks promising.  I just wanted to check what others are using before I couple myself to this API.


5d mk iv - Problems setting the speed to faster than 1/200th using both Manual or TV when I have my speedlite attached. Totally confused as I can't figure out why I'd be limited to that or how to change it. I've looked at the manual and it's says High speed sync is possible but doesn't say how????  I was shooting a fashion show today indoors and really needed a faster speed for bits of it??   Any help would be appreciated :)

When referring to flash exposure, what does "max sync speed" mean?


When I try to merge the interface areas by dragging from the corner, it either merges them, or creates a new area. I don’t understand how it works, it’s like the principle of randomness - sometimes it merges, sometimes it creates a new area. I know about a working alternative, but I would like to understand how to work through dragging from the corner. My Answer - The corners of the area are not common, they are separated, respectively, the commands on the areas work normally, exactly as needed, if you, when executing the command through dragging the corner, take the corner of the area - from which you plan to perform the action - divide the zone the corner of which you drag, or merge it with the neighboring one zone

I can't figure out how to close or split windows or panels in 2.8. In videos, to remove a panel it seems you somehow click in the upper right corner-doesn't work for me. To split a panel you somehow drag from the border and a new window appears. Can anyone help?  Thanks, Rusty


I was writing a report using latex and got issues with the bibliography page margin. First -[9] references have more left margins than rest of the other margins. I am using report class with bibliography style "abbrv". I even tried "IEEEtr" style and nothing changed.   \bibliographystyle{abbrv} \bibliography{mybib}

I have problem on how to make the bibliography item left-aligned. My current bibliography output is below.    As  you can see, the reference item code is currently right-aligned, and I need it to be left-aligned. Any idea on how to achieve that?  My current code for the bibliography is  \usepackage{natbib} %.... \nocite{*} \bibliographystyle{alpha} \bibliography{references}   Thank you.  update  Below is the code after i reduce many of it. The problem still occur on this code. I use MiKTeX 2.9.  \documentclass[bahasa, 12pt, a4paper, final]{report} \usepackage{babel} \usepackage{natbib} \usepackage{url}   \begin{document}     \nocite{*}     \bibliographystyle{alpha}     \bibliography{references} \end{document}


Identity is one of ESRI ArcGIS Feature that clipping feature class by another feature class then union first feature class to the result of clip process.  The simple explanation is like this picture below.   Is there any plugin or feature like this in QGIS? I'm using QGIS 2.14 Essen.

In ArcGIS, there is a tool called "." Say you have a bunch of points. Some points fall in polygons of interest, some don't. Each polygon has a unique ID. This tool will add a field to the points and assign the unique ID of the polygon that contains it. Is there a tool that does this in QGIS?   question does not ask the same question I am.


So, my laptop died. I have an old netbook. It has Ubuntu 10.04, and the upgrade manager says I can install 12.04. My question is, will this netbook run smoothly with it? Also, will it support newer versions?  The netbook is a Point of View Mobii 9040, with these specs:   Processor:Intel Atom N450 1.66 GHz Chipset:Intel NM10 Express Chipset Graphics chipset:Intel GMA 3150 Storage:250GB SATA  RAM:1GB DDR2 SDRAM LAN:RJ45 10/100Mbps   Thanks!

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


There doesn't seem to be a way to extend an existing JavaScript array with another array, i.e. to emulate Python's extend method.  I want to achieve the following:  >>> a = [1, 2] [1, 2] >>> b = [3, 4, 5] [3, 4, 5] >>> SOMETHING HERE >>> a [1, 2, 3, 4, 5]   I know there's a a.concat(b) method, but it creates a new array instead of simply extending the first one. I'd like an algorithm that works efficiently when a is significantly larger than b (i.e. one that does not copy a).  Note: This is not a duplicate of  -- the goal here is to add the whole contents of one array to the other, and to do it "in place", i.e. without copying all elements of the extended array.

How do I append an object (such as a string or number) to an array in JavaScript?


$A$ and $B$ are square matrices of order $n$.  Given $AB=BA$, prove that $\dim(R(A)\cap R(B)) \ge \text{rank}(AB)$.  Can I say that:  $\text{rank}(AB) \le \text{rank}(A) = \text{rank}(B)$  and  $\dim(R(A)\cap R(B)) \ge \dim(R(A)) = \text{rank}(A)$  Thus, $\dim(R(A)\cap R(B)) \ge \text{rank}(AB)$?  I think there's a lot of flawed reasonings. Would appreciate it if someone can enlighten me. Thanks!

If $A$ and $B$ two $n\times n$ matrix such that $AB=BA$, then my guess is $\dim(A\cap B)\geq \dim AB$. But I am unable to prove this. Any help in this direction is highly appreciated.  Thanks.


Low-rep users can't leave comments. This leads to many users   While the rationale behind this limitation is understandable, seen from the outside, it looks  inane and bureaucratic. New users often have useful information to bring to the table. That information is often enough destroyed through deletion,  or has to be manually converted to a comment by a moderator.  How about, experimentally for a month or so, removing the limitation, allowing comments from (registered) new users, and countering the threat of garbage comments with    A comment review queue for low-rep users' comments A lowered flagging threshold for low-rep users' comments (say, 2 flags instead of 3 or whatever is required right now)   After all, features like  show that there's value to be gained from the input of the countless visitors who end up on Stack Overflow through Google, but are never going to become active members of the community. So why not use it?

I've seen so many should-be-a-comment "edits" or "answers" in the review queues by new users, and it's pretty obvious that to them this was the only way to somehow interact with a question due to their lack of allowance to leave a comment. And sometimes (just sometimes) this comment would contribute something useful. So it's a shame to waste reviewers' time to first figure out that a suggested "edit" / "answer" should actually be a comment and then not exactly having tools to turn the former into an actual comment. If the new user would instead have had the possibility to clearly indicate that they wanted to leave a comment which would then be put into a simple "comments (by low-rep users)" review queue, where reviewers could maybe even leave one of the (more specific) automated comments à la "You should ask this as a new question" (where new question might even not only link to the "ask question" site but put the users comment into the title or body). And until approval the comment would by default by hidden by a "on hold" line that only higher-rep users, say >500, could toggle to view (and vote to approve directly in place). This is typical practice in many blogs' comments, and I think since we're community reviewing anyway this might be improve the hijacking situation. edit Note that by design those automated comments would not need to trigger a notification to the post's OP but only to the commenter. Whether the un-reviewed comment should already trigger a notification to the OP or not is a different question. I propose not, since the obvious once-in-a-while spam comment would be easier detected by a reviewer who is currently concentrating on specifically determining the validity of a comment. edit2 As noted in  these auto-replies should not clutter the original post - once a comment has been determined "Actually I want to ask a new question" they (and the reply) won't show up below the post except for the original commenter who will also be notified if they registered.  In summary:  Low-rep user posts a comment -> Below the post there will be a "1 comment under review" link and that comment will be added to the comment-review queue (see images below). No notification will be triggered for the OP, since the high likelihood of an unjustified comment was the reason for comments originally not being post-able by just anyone If a reviewer approves the comment, it will show up like any usual comment and now a notification to the OP (and @replied-to users) will be sent If a reviewer rejects the comment (with an optional reason as reply), it won't be shown below the original post as "under review" anymore. It, together with the reply, will be visible to the original commenter who will be notified, but no one else will be bothered by it edit3 As per : The commenter will not be able to post further comments until their comment is either reviewed or self-deleted. As , a negative review/flag should refute that user's ability to comment any more (or reduce a very low contingent of unreviewed comments allowed)


Just for fun, I defined the following series. For $m\in\Bbb N$,  $$g_m=\sum_{n\geq1}\prod_{i=0}^{m}\frac1{n+i}$$ I am seeking a closed form for $g_m$. I found $g_1,\ g_2$, and a general expression involving a lot of integrals.  $$ \begin{align} g_1=&\sum_{n\geq1}\frac1{n(n+1)}\\ =&\sum_{n\geq1}\frac1n\int_0^1 t_0^n\mathrm{d}t_0\\ =&\sum_{n\geq1}\int_0^1\int_0^{t_0} t_1^{n-1}\mathrm{d}t_1\mathrm{d}t_0 \\ =&\int_0^1\int_0^{t_0}\sum_{n\geq0}t_1^{n}\mathrm{d}t_1\mathrm{d}t_0 \\ =&\int_0^1\int_0^{t_0}\frac{\mathrm{d}t_1}{1-t_1}\mathrm{d}t_0 \\ =&1 \\ \end{align} $$ Through the same process, it can be shown that $g_2=\frac14$. In fact, through the same process, it can be shown that  $$g_m=\int_0^1\int_0^{t_0}\int_0^{t_1}\cdots\int_0^{t_{m-2}}\frac{\mathrm{d}t_{m-1}}{1-t_{m-1}}\mathrm{d}t_{m-2}\cdots\mathrm{d}t_2\mathrm{d}t_1\mathrm{d}t_0$$ Which I don't even know how to approach. Any ideas? Thanks.  This isn't a duplicate question, because I would like to know how to evaluate those nested integrals, if possible.

Lets define the following series $$S_n =\sum_{i=1}^{\infty} \frac 1 {i(i+1)(i+2)...(i+n)}.$$ I know that $S_0$ does not converge so let's suppose $n \in N$ and define $S_n$ for some $n$. We have $S_1=1$ , $S_2=\frac1 4$ , $S_3=\frac 1 {18}$ , $S_4=\frac 1{96}$ , $S_5=\frac 1{600}$ etc.. the numerator in all results is 1the pattern in denominator is $[1,4,1,96,600...]$ and   that is equal to $n*n!$ Finally I want to prove the general equality: $\sum_{i=1}^{\infty} \frac 1 {i(i+1)(i+2)...(i+n)}=\frac 1 {n*n!}$


In my package, I request amsmath with \RequirePackage{amsmath}, resulting in this basic setup:  \documentclass{minimal} \usepackage{amsmath} \usepackage{mathspec} \RequirePackage{amsmath} % part of another package, \usepackage{...} \begin{document} hi \end{document}   This leads to the error     Package mathspec Error: 'amsmath' must be loaded earlier than 'mathspec'.   at the 2nd request for amsmath, although amsmath is already loaded.  I could, of course load my package before mathspec. However, a user of my package has the problem that he uses a template and cannot load packages before  mathspec, only after it.   I'd consider this a bug. The error should not be raised when amsmath is already loaded. Do you agree? Is there a way I could change my package (replace \RequirePackage{amsmath}) to avoid this error?

MWE: greatly trimmed from a large document; XeLaTeX; full TeXLive2012 completely up-to-date:  \documentclass{memoir} \usepackage{fixltx2e} \usepackage{amsmath} \usepackage{mathspec} \usepackage{glossaries} \usepackage{lipsum} \begin{document} \lipsum[1] \end{document}   Fails with "! Package mathspec Error: 'amsmath' must be loaded earlier than `mathspec'."  Now, if I eliminate glossaries, or move it above mathspec in the file, things work. But it isn't very convenient to have to sort ones packages whenever anything gets a new dependency. And in any case, I do load amsmath before mathspec, don't I?  Really puzzled by this one. Any illumination would be most welcome.  (BTW, not strictly MWE, as it also fails with article.


So the full question goes as following:  Let $0<r<1$.   If $x>0$ or $-1\le x<0$, show that $(1+x)^r < (1+rx)$  I'm having a real hard time getting the idea of the usefullness of MVT. It seems every approach I take is faulty.  I don't know how to think. If I take $f'(c)$ for $0<c<x$ I get $(1+c)r -1 / c$ which I can conclude is larger than $0$,  which leads me nowhere.  Help is very appriciated!

Using Bernoulli's Inequality show that $$\left(1+\frac{1}{k+1}\right)\left(1-\frac{1}{(k+1)^2}\right)^k\geq 1$$for all $k\in\mathbb{Z^+}$.   My initial thought was to start be noting that \begin{align*}1-\frac{1}{(k+1)^2}&\geq 1-\frac14 \text{ for all natural $k$}\\\implies\left(1-\frac{1}{(k+1)^2}\right)^k&\geq\left(1-\frac14\right)^k\geq1-\frac k4,\end{align*}by Bernoulli's Inequality. Multiplying both sides by $(1+1/(k+1))$ gives the required expression on the left hand side, but the expression on the right hand side is not always greater than or equal to one. So my approach is clearly flawed.   However, if I use Bernoulli's Inequality as follows $$\left(1-\frac{1}{(k+1)^2}\right)^k\geq1-\frac{k}{(k+1)^2}$$ and multiply both sides by $(1+1/(k+1))$ I get an expression greater than or equal to one. However, this seems to me completely false; isn't Bernoulli's inequality $$(1+x)^k\geq1+xk$$ supposed to work for a variable real $x>-1$ and a fixed natural $n$?  Any help will be appreciated.


When I'm specifically not mentioning if its MS or MEngg degree. What is the correct way to say -  pursuing master's/masters/Masters/Master's in Electrical Engineering and during my bachelor's/bachelors/Bachelors/Bachelor's in Electrical Engineering at Univ f Gotham?

When someone states "I have a Masters in Computer Science" should the word masters have a capital M?  I've seen arguments for both and can't determine which is correct.


I've had a Canon T3i for about a year now, getting it as an upgrade to a small Canon point-and-shoot.  I mainly got the T3i for the additional shooting setting controls and the ability to change lenses.  However, a year has gone by, and I find myself leaving my DSLR on my desk more often than not.  I dislike carrying the camera, since it is so large and obtrusive, making taking photos day-to-day feel like a big production.  I have only bought one additional lens (50mm f/1.8 prime), and I feel that the ability to swap lenses is a bit of a waste on me.   What this year with the T3i has taught me is that I enjoyed photography more when I had a smaller camera, which I could be more spontaneous with and was more willing to carry.  As such, I have been considering selling my T3i and getting a Fujifilm X20, which I would feel more comfortable carrying, yet still have the same degree of control over shooting.    My question is, what is the potential for regretting the change from a DSLR to an X20?  Some additional information:   I do not shoot sports or other very fast subjects. (I've heard the X20 has rather quick phase-detect AF)  Image quality is not paramount, as I only shot JPEGs with the T3i anyway. I want to be able to carry my camera comfortably and discreetly every day. Lens interchangeability is not a concern.   Thank you

Why should I put up with the inconvenience of lugging around a DSLR?  They look cool, but is there more substance to it?


So, I was marking a C++ test while our senior programmer was away and the very first question was something like this:  Without compiler optimizations, which method will run faster? Method 1 for(int i = 0; i < 100000; i++) { } Method 2 for(int i = 100000; i >= 0; --i) { }  Now, If you're like me and almost every other developer I've encountered (save now for one), you've been led to believe that pre-increment & pre-decrement operators (++i and --i) are inherently slower than post-increment & post-decrement operators.  So naturally I went with Method 2. However, our senior programmer returns and tells me that the two functions will run in equal time. Thinking it was all some elaborate joke, I set out to prove him wrong and whipped this up: #define ITERATIONS  (1000000000) clock_t start = clock(); for(int64_t i = 0; i < ITERATIONS; i++) {} auto first_clock = clock() - start;  start = clock(); for(int64_t j = ITERATIONS; j > 0; --j) {} auto last_clock = clock() - start;  Much to my surprise: first_clock = 25333 last_clock =  25277  For all intents and purposes, these methods are equal! So, where did this myth come from?  Was it true at one time and became false in newer compilers?  Looking forward to an interesting discussion. :)

Is there a performance difference between i++ and ++i if the resulting value is not used?


I´m currently working on a calculator and i want to skip 2 lines of my code if the second Scan equals a specific word. In this case the word is either "Wurzel" or "wurzel" because i wont need to scan b then.       Scanner eingabe = new Scanner(System.in);     BigInteger a, b, ergebnis;     String Operator;     System.out.println("Bitte gib die erste Zahl ein:");     a = eingabe.nextBigInteger();     System.out.println("Bitte gib die Rechenart ein:");     Operator = eingabe.next();     if(Operator == "Wurzel" || Operator == "wurzel" ) {         //skip to switch(operator)     }     System.out.println("Bitte gib die zweite Zahl ein:");     b = eingabe.nextBigInteger();     switch(Operator) {        ...      }

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?


Let's say I have example.com domain, and I force the user to use the HTTPS over HTTP.  The question is as browsers just accept and load the forwarded/new page (when the request for http://example.com -> https://example.com), does the Googlebot (or other search engines) accept the forwarded page and index the new page and just ignore the old page?  In other word, does search engines accept HTTPS beside the HTTP?

I have a website http://www.domain_1.com/ hosted in a shared webserver.  I have used SSL for another website https://www.domain_2.com/ on the same server.  Due to some technical limitations (single IP), if you try https://www.domain_1.com, browser will show the same domain_2 website. But this is not a concern for me.  Question: will this scnario impact SEO of domain_1 (non-HTTPS) site?


I've always appreciated the "main" link in the MSO header, just as I appreciate the "meta" link in the SO header, as I frequently go back and forth between the two.  I just wanted to confirm that there are currently no plans to bring a "main" link back and no alternative in the current design to the tedious "click, search the drop down, navigate to the MSO link, click again" process that's now in place to navigate back.  (That's four physical/mental operations vs. one).  Along the same line, should I expect the "meta" link to go away from SO when it migrates to the new design?  Update: See in particular this  to the close-as-dup question reference.

EDIT Dec 4 -  We're doing it live! Please post bugs or concerns as questions tagged [top-bar]  We have rolled out our 95% completed top bar for feedback.  Note:   We are still adding a few final features, so if you have a request for a feature that is not there you might hold off on that for a day or two Yes, the bar is black1. Also give that a day or two to sink in.   I also want to specifically address the meta/main/chat links.  I'm very aware that many of you like having the links at the top of the page and that this new version is different.  The thought process behind moving these links is that the "site switcher" should be an automatic place to go when you are on a site and want to go to another one. If you haven't already developed the muscle memory for these links, getting between them required a bit of a cognitive load: You must first decide that you want to switch sites and then you have to decide which area to go to to switch.  Also, we find that less familiar users aren't entirely clear what a standalone link that says "main" or "meta" actually does... Not to mention that it hurts my UX sensibilities that we are dynamically changing links in an element that should be fixed.  It is true that we have added a click in the process, but we have also removed a lot of clicks for other common actions that are much more frequent than switching between main and meta.  All I ask is that you give it a few days and see if the new "switch sites at the top left" paradigm grows on you.  What do you think?  1.  points out that technically it's not quite black.


I am running 19.10 on a Lenovo flex 11 and all seems to be working smoothly. I regularly check for updates and often get something new installed apparently. Well, today I checked for updates and get the message "Failed to load repository information". My network connection is good...hello, my question is getting in here...so what is going on? Fetching e-mail works, surfing the web works, streaming works, but am unable to download repository information. What's up? results of update attempt:  tom@tom-Lenovo-FLEX-6-11IGM:~$ sudo apt update [sudo] password for tom:  Ign:1 http://dl.google.com/linux/earth/deb stable InRelease Hit:2 http://us.archive.ubuntu.com/ubuntu eoan InRelease                     Hit:3 http://us.archive.ubuntu.com/ubuntu eoan-updates InRelease             Hit:4 http://us.archive.ubuntu.com/ubuntu eoan-backports InRelease Get:5 http://dl.google.com/linux/earth/deb stable Release [933 B] Get:6 http://dl.google.com/linux/earth/deb stable Release.gpg [819 B] Hit:7 http://security.ubuntu.com/ubuntu eoan-security InRelease Ign:6 http://dl.google.com/linux/earth/deb stable Release.gpg Reading package lists... Done W: GPG error: http://dl.google.com/linux/earth/deb stable Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 78BD65473CB3BD13 E: The repository 'http://dl.google.com/linux/earth/deb stable Release' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. tom@tom-Lenovo-FLEX-6-11IGM:~$   my ignorance is nearly complete, but it appears to me that something may be lacking in the place where updates live - I am grateful for the assistance I get here.

I added some extra repositories with the Software Sources program. But when I reload the package database, I get an error like the following:     W: GPG error:  trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8BAF9A6F   I know I can fix it using apt-key in a terminal, according to the official Ubuntu documentation. But I would have liked to do it graphically. Is there a way to do this without using a terminal?


If I may ask: How can the orbits of binary pulsar stars, with similar mass, be calculated from Kepler's laws? Considering that both large central masses must be located at their mutual foci. Also, how can the period be in proportion to each semi-major axis? Can one closed implicate calculation be used, or is it only arrived at recursively (excluding computer algorithms).

For simulation purposes, I'm trying to create a binary star system. If I have a conic equation such as $ax^2 + by^2 = c$, and the masses of two stars, how would I find the $x$- and $y$- velocity vectors (let's assume one star is the reference point, fixed in space), so that one star's orbit is stable and described by the conic equation?


all. I'm trying to get a value from a document, that looks like this:  {       "id" : player:(some number)",       "name" : "Martinez, Javi",       "type" : "midfielder",       "jersey_number" : 8,       "position" : "Central defender"     }   I have players in an ArrayList<Document> playersOnPitchHome and want to find one with a particular "jersey_number"  My code (below), however, is giving me a NulPointerException in the row I've highlighted with the //here comment. As far as I understand, the exception is not occuring due to me accessing playersOnPitchHome  The Code:  Document player = playersOnPitchHome.get(0);        int i;        for (i=0; i<playersOnPitchHome.size(); i++) {            player = playersOnPitchHome.get(i);            int numberTemp = (int) player.get("jersey_number"); //here            if (numberTemp == playerNumber) break;            if (i==(playersOnPitchHome.size()-1) && numberTemp != playerNumber) {               throw new Exception ("there is no such player on the pitch");           }      }   Thank you in advance.

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 trying to pass a function name and its parameters as parameter and call it   Here is the code  $(document).ready(function(){     runfn(getUserName,paramValue); });  function runfn(fnName,param){     fnName(param); };  function getUserName(userId){     alert(userId); };   Feel free to edit   i want to call function with parameters using this method

I have the name of a function in JavaScript as a string. How do I convert that into a function pointer so I can call it later?  Depending on the circumstances, I may need to pass various arguments into the method too.  Some of the functions may take the form of namespace.namespace.function(args[...]).


How do I export a System.Web.UI.WebControls.Datagrid to an Excel file in C#? (without any 3rd party sw). Note that I am starting with a DataGrid, not GridView or DataGridView. I see examples for this with DataGrid and DataGridView on SO, but not DataGrid. I also see examples like this:  which converts to html and apparently has performance issues.

whats the best way to export a Datagrid to excel? I have no experience whatsoever in exporting datagrid to excel, so i want to know how you guys export datagrid to excel. i read that there are a lot of ways, but i am thinking to just make a simple export excel to datagrid function.i am using asp.net C#  cheers..


Just out of curiosity: Is there a way to compile latex document with two document classes at once?  Suppose that I have a paper which start with line: \documentclass[preprint,authoryear,12pt]{elsarticle}  But finally I would like to compile it with such line: \documentclass[final,5p,times,twocolumn]{elsarticle}  Obviously I can replace these lines and compile file twice, but I wonder if there is any trick to avoid double compilation?

I'd like to be able to create a TeX file that will output multiple PDF files with one compilation.  I'm not even sure if this is possible.  Here is the setup:  I am writing dozens of cover letters for job applications, and wish for them to all look "personalized".  So I defined a function which calls multiple variables, such as the address, name of the institution, open position, etc., and outputs a "personalized" cover letter for each function call.  The problem is that compilation of the TeX file outputs just one file.  Since I will be submitting all of these files online eventually, I would like each letter to be in its own file.  Is there a way to do this at the TeX level?


So, I have a list of strings in python, and I am trying to find which keys are numbers. I am trying to use list.[key].isdigit() but it only works with '0' For instance:  list = ['0', '0', '0', '0.450000000000000', '0', '0', '0', '0.550000000000000']   will only determine that '0' is a digit, but '0.45' and '0.55' are not. How can I fix this problem?  Thank you very much

What is the best possible way to check if a string can be represented as a number in Python?   The function I currently have right now is:  def is_number(s):     try:         float(s)         return True     except ValueError:         return False   Which, not only is ugly and slow, seems clunky. However I haven't found a better method because calling float in the main function is even worse.


I've just started learning Java and now I'm into for loop statements. I don't understand how ++i and i++ works in a for-loop.  How do they work in mathematics operations like addition and subtraction?

Is there a difference in ++i and i++ in a for loop? Is it simply a syntax thing?


I am porting a lot of code from PHP to Java (an Android application). Everything is done but I am facing a problem here,  I got this PHP code:  class SenderKeyGroupData{   const MESSAGE = 1;   const SENDER_KEY = 2;   /* @var array Field descriptors */   protected static $fields = array(       self::MESSAGE => array(         'name' => 'message',         'required' => false,         'type' => 7,       ),       self::SENDER_KEY => array(           'name' => 'sender_key',           'required' => false,           'type' => "SenderKeyGroupMessage",       ),   );   However I want this code in Java, for example I created this Java code:  class SenderKeyGroupData {     int MESSAGE = 1; // Must be const     int SENDER_KEY = 2; // Must be const      // These two Maps must be in the $fields array?     Map MESSAGE = new HashMap(); //Duplicate conflict here     MESSAGE.put("name", "message");     MESSAGE.put("required", false); // Map can't contain booleans?     MESSAGE.put("type", "7");      Map SENDER_KEY = new HashMap(); //Duplicate conflict here     SENDER_KEY.put("name", "sender_key");     SENDER_KEY.put("required", false); // Map can't contain booleans?     SENDER_KEY.put("type", "SenderKeyGroupMessage"); }   I described the problems as comments. All ideas are welcome.  Note that the const contain 1 and 2 as value in the constructor, but also get an array assigned. So please give an example instead of pointing it as duplicate.

I've seen examples like this:   public class MaxSeconds {    public static final int MAX_SECONDS = 25; }   and supposed that I could have a Constants class to wrap constants in, declaring them static final. I know practically no Java at all and am wondering if this is the best way to create constants.


Is $I=(x,y)$ seen as an $\mathbb C[x,y]-$module is free ?  I would say that $\{x,y\}$ is a basis but since $x$ and $y$ are in $\mathbb C[x,y]$, may be it's not true.

Given a field $K$ we have the polynomial ring $K[x,y]$ in $2$ variables, which is also a left module (over itself). How can we prove that the ideal $(x,y)$ is not a free module?


I know there are many other same related questions, but as my profile says I don't have a mentor, I just wanted you guys to check my solution. First I noticed that, $11$ = $10 + 1$, $111$ = $10^2+10+1$, Similarly, $\underbrace{111\cdots111}_{n\,\text{times}}$ = $10^{n-1}+10^{n-2}+...+10+1$, which  can easily be evaluated as it is a finite geometric series. $$\sum_{i=0}^{n-1} 10^i=\frac{10^n-1}{9}$$ for $n \ge 2$. After this, I checked perfect square modulo $4$, Let $j$ be any integer, then if $j$ is even, then $j=2k \Rightarrow j^2 = 4k^2 \equiv 0 \mod 4$ and if $j$ is odd then, $j = 2k+1 \Rightarrow j^2 = 4k^2+4k+1 \equiv 1 (\mod4)$ Then, Since $\underbrace{111\cdots111}_{n\,\text{times}} = \frac{10^n-1}{9} \Rightarrow (9) (\underbrace{111\cdots111}_{n\,\text{times}}) = {10^n-1}$ $\equiv$ $2^n-1$ $(\mod 4)$ $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv 2^n-1 \mod 4$ Since for $n \ge 2, 2^n$ is always a multiple of $4$. Hence, $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv -1 \mod 4$ $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv 3\mod 4$ But a perfect square leaves remainder $0$ if it is even and $1$ if it is odd. So, clearly for $n \ge 2,$  $(\underbrace{111\cdots111}_{n\,\text{times}})$ is not a perfect square. I know there are other questions related to this but I just wanted to verify if my solution was correct. Thank you and suggestions would be appreciated!

Please help me with solving this : prove that none of $\{11, 111, 1111 \ldots \}$ is the square of any $x\in\mathbb{Z}$ (that is, there is no $x\in\mathbb{Z}$ such that $x^2\in\{11, 111, 1111, \ldots\}$).


Got this question during an interview.  I was talking about two threads modifying one same dictionary which causes wrong data.

I've been trying to wrap my head around how threads work in Python, and it's hard to find good information on how they operate. I may just be missing a link or something, but it seems like the official documentation isn't very thorough on the subject, and I haven't been able to find a good write-up.  From what I can tell, only one thread can be running at once, and the active thread switches every 10 instructions or so?  Where is there a good explanation, or can you provide one? It would also be very nice to be aware of common problems that you run into while using threads with Python.


So, I have a batch that runs through a file system, and checks the size of the files in it and renames them with a different extension if the size is zero bytes. That part was easy, but now I have to check to see if what's currently being looked at is a file or a folder.   here's my code so far.   SET FTPFOLDER="C:\temp"  rem this goes thru a folder system. for /f %%f in ('dir /b %FTPFOLDER%') do (call :Search "%%f")  EXIT /B 0   REM GOES THRU EACH OF THE FILES IN EACH OF THE FOLDERS :Search for /f %%g in ('dir /b %FTPFOLDER%\%~1') do(call :checkType "%%g", "%FTPFOLDER%\%~1\%%g\", %%~ng  ) pause EXIT /B 0  :checkType if exists %~1\* (call :Search %~1) else (call :checkSize %~2, %~3) EXIT /B 0  REM CHECKS IF ZERO  :checkSize set file=%~1 @echo %file% for /f "usebackq" %%h in ('%file%') do set size=%%~zh if %size% EQU 0 (call :Rename "%file%", %~2) EXIT /B 0  REM - RENAMES FILE TO .EMPTY :Rename ren %~1 %~2.empty  EXIT /B 0   Nothing I've tried so far has worked. I am extremely new to batch, so any and all help would be appreciated, especially with explanations.  Edit: I feel that it's also important to mention that no file names or folder names will have spaces.   Edit: I have changed my code to remove the extra function, and do it in the for loop. My new code is as follows  SET FTPFOLDER="C:\Users\nmavis\Desktop\gndjufsb"  rem this goes thru a folder system.  for /f %%f in ('dir /b %FTPFOLDER%') do (call :Search "%%f")  EXIT /B 0  REM GOES THRU EACH OF THE FILES IN EACH OF THE FOLDERS :Search for /f %%g in ('dir /b %FTPFOLDER%\%~1') do (if exist %%~sg\NUL (echo dir) else (echo file)) pause EXIT /B 0  REM CHECKS IF ZERO  :checkSize set file=%~1 @echo %file% for /f "usebackq" %%h in ('%file%') do set size=%%~zh if %size% EQU 0 (call :Rename "%file%", %~2) EXIT /B 0  REM - RENAMES FILE TO .EMPTY :Rename ren %~1 %~2.empty  EXIT /B 0   However, whenever I run it, no matter whether or not it is a file or a folder, it displays "File"

Is there any way to find out if a file is a directory?  I have the file name in a variable. In Perl I can do this:  if(-d $var) { print "it's a directory\n" }


Yesterday I deleted  (now undeleted again) because . That plan worked. What I find strange is that in my  the link to that answer is not present.  Should I blame caching or is there another reason that the deleted answer didn't make it onto my list? My answer was posted on sep, 11th and edited on sep, 30th...

On the bottom of questions tab of the user profile, there is a link that states "Deleted recent questions".    This links to http://site.stackexchange.com/users/recently-deleted-questions/xxxxx.  The title of the page is 'User Flair', which seems odd in itself.  What is this page meant to show?  Whenever I have looked at it it is blank for me, to test I deleted  on Android.SE however six hours later the recently deleted questions page was still blank.    Is this feature not working, am I incorrectly interpreting it (for example is it only moderator/community deleted questions) or was my experiment a failure due to long term caching? Having now re-read the link I see that whilst the title is "Recently deleted questions", the link is to "deleted recent questions" - does the question have to have been recently asked?


I'm trying to understand the reason for a difference in speed on my Wifi network vs using an ethernet cable. Hooking a laptop directly into the cable modem shows speeds 28 Mbps down and 5 Mbps up (Speedtest.net results). If I hook it up via ethernet to the router it maintains that speed. So the router itself doesn't cause a slowdown. But if I switch to wifi my download speed drops 8-10Mbps.  This is when the laptop is right next to the wireless router so it's not due to distance. I have also tried switching to the different channels and have received similar results. I realize the 54Mbps advertised by the wireless router is somewhat of the theoretical speed and it might be below that. But it should be able to handle the 28Mbps I would think without a problem. The link speed showing on my computer is 54Mbps so the computer thinks it has a good connection. What else am I missing?

Using a wired connection, I get a 38 Mbit/s download speed. When I switch to wireless one (Linksys WRT54GL router with Tomato firmware), the speed drops to 23 Mbit/s even if the distance between the router and the computer is 2 or 3 meters.  Is that a maximum effective bit rate I can expect from an 802.11g connection? Are there any settings I can tweak to to increase the download speed?


I vaguely recall a made-for-tv? movie (25ish years ago) and I remember some plot points but I can't seem to track it down by googling. I may be mis-remembering some of the details. A corporate suit comes home and starts to get romantic on the kitchen floor with his wife but the dishwasher overflows and water spills out on to the floor. Sparks fly and low and behold, his "perfect" wife is revealed (to the audience) as an android. He's told that she's a (rare? obsolete?) model, and there's no parts to repair her. But there may be some in this lawless-dystopian-post-apocalyptic-wasteland-type area. So he hires this guide (female, red hair?) to help him search for the parts. They end up falling for each other. They eventually find the parts and repair robo-wife, but he realizes that her companionship is shallow compared to the hard-living and very real woman he hired to help find the parts and I seem to remember that he leaves the android behind as explosions are happening.

I vaguely remember watching a science fiction movie with my mother sometime in the 80s (I was born in 84, so I'd be quite young at the time)... The movie was from the 80s, and this is what I remember about it:  The main character has a female "companion" droid that looks just like a human female.  Something happens to her, and he wants to "fix" her, but there is only one place he might find an identical model, which is somewhere in a desert?  Her "mind" (hard-drive/emotions/memories) is stored on some kind of removable media, I want to say it was like a CD, but I'm not sure. It was located somewhere around the back of her head, maybe under the hair?  I seem to remember the droids being stored in clear-vinyl body-bags inside a pyramid-type structure in the desert?  I want to say the film had a lot of visuals and themes reminiscent of blade runner, flying cars and such.


I want to know the difference between 'to be' and 'to become'.  There are two sentences below   I want to be a president. I want to become a president.   I think the two sentences are same. If not, what is the difference in meaning? What do you think of this?

I am not good at English. And I used to say that I want to become a software developer. But Some people are using that I want to be a [something]. Which one is correct? And at what situations we should use which one? I read in many websites. Answers I have found so far are  Be is abbreviation of become. Both are same. Be is representing continuous thing. Become represents future.  I can't understand it because of people usage. Could anyone please further explain the difference between these two?