I am a student of 11th grade and i have completed the syallabus of both 11th and 12th grade maths with complete understanding and it was possible coz of the love for this subject that i have. I don't want to sound "larger than life" here, but my curiousity has now increased to learn maths at a deeper level. As of now i am reading "Linear algebra done right" by Axler. Thats an amazing piece of work and now i truly understand what "matrix" is all about. I also want to extend my knowledge on the following topics :  1) Algebra (groups,subgroups,homomorphisms etc)   2) Analysis   3) Geometry/Topology  Why i am here is because i wanted you guys to recommend a book on each of the above topic that would be appropriate for a beginner like me (I must mention here I have been working on Apostol's volume 1 calculus, thats a great text, but for a beginner, its best if the concept is explained in a broad manner and in as simple and easy words as possible) . I just want a book which explains the concept broadly rather than coming to the conclusion directly (which is not a great sight for a beginner like me) .   Having said that, no book is complete i understand. Thats why i am asking your recommendation as you guys are aware which text would be the best to start with for a beginner. I have searched on the net about this, but there are dozens of works available, and out of them all , i want the one which is the best (approximation) for a beginner .   Please don't misunderstand me in any way. I am just confused which text to go for, and i understand the books which u may suggest may be for undergraduate level course as these topics are for undergraduate level courses, thats not a problem at all . I need a easy to learn (i mean easy in terms of "broad" explanation) book. I hope you guys don't mind me questioning such a question on this forum . Thanks for all the help you guys have been providing me on this forum . Maths Maths Maths... the world is beautiful coz of u! :))


Use induction to "establish" the divisibility statement $8 | 5^{2n}+7$

Use induction to establish the divisibility statement $8 | 5^{2n}+7$. I am going to assume that establish means prove here. Here a hint is given: $5^{2(k+1)} + 7 = 5^{2}(5^{2k} + 7) + (7 - 5^{2} * 7)$. As far as I can see from a glance it's obvious that the value of $0$ for n works but I still don't know  how to prove that using induction here.


to extract substrings from file path using regex in java

I am new to regex and i want to extract strings from file path. Below is the mentioned filepath from which i want to extract string:  input : c://dev-dl-data-d2-us=east-1-5148727/all/stage/clinical/cro/raw/c/ca209_040/2018/08/02/aesae.csv  Output: ca209_040,aesae.csv


So I was solving a previous year question paper and stumbled upon the following question- $${\lim_{n\to {\infty}}}\biggl(\tan x+\frac{1}{2}\tan \frac{x}{2}+\frac{1}{2^2}\tan \frac{x}{2^2}+\frac{1}{2^3}\tan \frac{x}{2^3}+{\cdots}+\frac{1}{2^n}\tan \frac{x}{2^n}\biggl)$$ The only limit with $\tan$ that I have learnt is ${\lim_{x\to 0}}\frac{\tan x}{x}=1$. I have tried the following with no success- 1)Representing $\tan x$ in terms of $\tan \frac x2$   2)Simplifying into $\sin x$ and $\cos x$   I do not want a complete solution but would greatly appreciate a hint on how to simplify the series.


cat a file to show the 1st line and the grep queried value


Fault tolerant cross datacenter MySQL replication & failover strategy

Which of the following method is the most fault tolerant way to achieve cross datacenter MySQL replication using  and why?   MySQL master-master replication with one primary/active node and the other acting as hot spare. When the active node is down, the DNS failover switches to hot spare. Question: Does this setup achieve two-way sync reliably & automatically since both nodes are slaves to each other? If yes, the only manual action required would be to switch DNS to primary once its up and sync is complete. MySQL master-slave replication with master as primary/active node and slave acting as hot spare. When the active node is down, the DNS failover switches to hot spare. This setup requires manual recovery of master from slave after failover as explained  or . Question: Is this more reliable or fault tolerant than option 1? (I've read of master-master replications having issues with conflicts and sometimes even where both the DBs are out of sync).   What other better options are there that are similar in complexity to setup/manage?  Updates:  Tested out option 1 today with a very complex stack and so far so good. The DNS FO and fault-tolerance is pretty good for production use.


Why do some authors use terms "non-ascending" and "non-descending" instead of ascending and descending?

In my math book, everywhere the author has used "non-ascending" instead of descending and "non-descending" instead of ascending. I was wondering if there is some special meaning or use associated with it?  Because the way I see it is that it just increases the number of words and wastes ink.


Tracking disk I/O by application in Windows?

Is there a utility for Windows that operates similarly to iotop for Linux?  I'm looking for simple tool that can tell me what applications are writing to disk and how much they're actually writing.


Why does the sum of 2 parseFloat variables give me an incorrect decimal number

If I have this little function:  <script type="text/javascript">   function printFloat(){       var myFloatNumber1 = document.getElementById('floatNumber1');       var myFloatNumber2 = document.getElementById('floatNumber2');       alert(parseFloat(myFloatNumber1.value) + parseFloat(myFloatNumber2.value))  }  </script>  <input type="text" id="floatNumber1"></input> <input type="text" id="floatNumber2"></input>  <input type="button" onclick="printFloat()"/>   in field 1 I enter: 221.58 in field 2 I enter: 2497.74  I expect the sum of 2 numbers in the input fields to be a 2 number digit: 2719.32 But the result is a incorrect number... : 2719.3199999999997  a round would do the job, but I just don't get why the code does that on this number... On other number combinations, the sum is correct...


No Indian (and Bengali) keyboard layout in Ubuntu 17.04?

I've upgraded from Ubuntu 16.10 to 17.04 today. I'm from Bangladesh, and Bengali is my native language. There was an option to set keyboard layout to Bengali in all previous Ubuntu versions I've used. But there's no such option in 17.04, strangely. I can use Bengali by installing the package ibus-m17n,  so I thought maybe there was some problem during my upgrade. But then I checked my friend's PC which runs ubuntu 16.10 and found that ibus-m17n was not installed in 16.10 but there's option for Bengali keyboard layout. So is Bengali keyboard support really removed from 17.04, or was there a problem during my upgrade?


I made this table (see attached picture) by mixing two tables but how could I create like this table


How can I make my own mesh and add it to Addmenu > Mesh?

As Blender is an open-source Program of coarse I can Edit its program files !  I want to make my own mesh (Car/Bus/) and I want it become a a regular mesh In add menu like a cube,sphere (Because I use it many times)  Why?  I do not want my mesh to be in file and every time i want to use i must imported.  How Can i Make it ? - Of coarse it will be made with Python - ( Are n't I right ? )  N.B : Plese in answer Be ware that i am new to blender python. bpy.  Refrence  Consider that this is my mesh:   And I Want Its Shortcut in This Menu Here:


I'm a Ubuntu novice and I'm trying to figure out how to use cloc to count lines of code in a directory.    I think I got it installed correctly using: sudo apt-get install cloc  However, I cannot figure out how to get it to scan a directory. The directory is here: Documents/My Work/Company/HostMedics/hm_site-updated  Although when I type in the terminal: cloc Documents/My Work/Company/HostMedics/hm_site-updated  I think this is the way I'm using the terminal. It seems to stop at My Work.  What do I type to get it to scan a directory?


Get a notification when new answers are added to other people's question

Possible Duplicate:             Is there a way to get a notification (either email or via the "stack exchange" drop-down/inbox), when a new answer was added to a question (which was asked by another user)?  I found this question: , but this is related to the envelope icon which no longer exists.


I built a cube under a white point light to build a material using Cycles rendering. When I finished building my material and went to bed after saving the file, the material was kind of white with grey spots.  When I opened the file this morning, the material is pink in color. Note, I have not made any changes at all to any aspect of the file, anywhere. So with it just becoming pink for no apparent reason, I have no idea how it happened or what to do to fix it.


Let $f:[0,\infty)\to\mathbb{R}$ be continuous and $\lim_{x\to\infty}f(x)=L$. Show that $$\int_0^{\infty}\frac{f(ax)-f(bx)}{x}dx=[f(0)-L]\ln\frac{b}{a}$$ where $0<a<b$.  I don't even know how to start.


How to change default viewport shading in 2.8?

Is it possible to change the default mesh color/shading in 2.8 to be more like 2.79? I'm finding it hard to see finer detail in 2.8. On the left is 2.8 and the right is 2.79


I simplified to get $6x^4-25x^3+12x^2+25x+6=0$  Or $6 (x^2+1)^2+25x(1-x^2)=0$  Then I substituted $z=x^2+1$, to get $6z^2+25\sqrt{(z-1)}(2-z)=0$  I can't find a way to proceed further.


Joint cumulative probability with dependent interval

Edit 2: Tried to make the question clearer by adding a graph  Edit: Please note: This is not a duplicate of another question I asked earlier (). The difference being that in the other question, $x$ and $y$ are correlated and hence their distributions are not independent -- i.e. $f_{X,Y}\neq f_Xf_Y$. Here, I am assuming that the two variables are independently distributed, but that the probability that I want to compute (i.e. the upper bounds of the interval) is a function of the other variable $a=u(Y), \ \ b=v(X)$.   I'm new to the site so please accept my apologies for asking anything to obvious.  I've got two independent continuous random variables $X$ and $Y$ with pdf's $f_X$ and $f_Y$, such that the joint density function is given by $f_{X,Y}$ and the joint cdf by $F_{X,Y}$.  I am looking for the joint probability $Prob(X \leq a,Y \geq b)$, where each variables' cut-off point is a function of the other variable, i.e. $a=u(Y)$ and $b=v(X)$. Essentially I need to integrate where the interval is dependent on the random variables:  $$\int^a\int_b f_{X,Y}(x,y)\,dy\,dx$$  Graphically, I am looking for the blue area:    which (I believe) should come down to $F_{X,Y} (a,y)-F_{X,Y} (a,b)$, but $a$ and $b$ depend on $X$ and $Y$, respectively.  Is there a way to find an analytical solution to this problem? Many thanks in advance even for a small hint. Much appreciated!


What is the definite integral $\int_{-1}^1 \frac{1}{x} dx$ equal to?

What is the definite integral $\displaystyle\int_{-1}^1 \frac{1}{x} dx$ equal to?  Is it $0$ like it would be if you just integrated and plugged in the bounds, or does the discontinuity at $x=0$ invalidate that line of reasoning and make this integral undefined. If you split up the integral $$\int_{-1}^0 \frac{1}{x} dx+\int_{0}^1 \frac{1}{x} dx.$$ You get $\infty-\infty$ which is undefined. I find it difficult to prove either of these solutions.


How can I recursively delete empty folders?   "Empty" is considered to be true if the directory has no directory and no files exist except for useless auto-generated files (Thumbs.db, .DS_Store, etc.)


Shortcut in Windows 7 to switch between same application's windows, like Cmd + ` in OS X

Is there a shortcut in Windows 7 to switch between windows in a given application only? I very much like this feature in OS X; what is its equivalent in Windows?


Can anyone tell me what exactly the difference between an completely abstract class and an interface?  An Abstract class can also have all its methods as abstract. An interface has all its methods as abstract. What is the main difference between the two in this scenario?  If there is difference between a pure abstract Class and interface? What is the use of interface? Where interface is being used we can make use of pure abstract class?


Lebesgue outer measure satisfies $\lambda^{*}([a,b]) \leq b-a$

Aaagain, I fail to understand the trivial:    Using compactness argument it is straightforward to show:  $$\lambda^{*}([a,b]) \geq b-a$$ And everything is OK.  But, regarding $\lambda^{*}([a,b]) \leq b-a$, Cohn says:      For any closed bounded interval $[a,b] \subset \mathbb{R}$ it is easy to see that $\lambda^{*}([a,b]) \leq b-a$ (cover $[a,b]$   with sequences of open intervals in which the first interval is barely larger than   $[a,b]$, and the sum of the lengths of the other intervals is very small).   From this hint I should be able to arrive at $\lambda^{*}([a,b]) < b-a + \epsilon$, for arbitrary $\epsilon >0$, but I don't understand how..  Help?


After 16.10 upgrade, ethernet is not working

Ok. I really need help. I messed up Ubuntu 16.04 LTS so I decided that upgrading to 16.10 will fix the broken packages. It did, but now I can't use the internet. At all. I have a Lenovo Ideapad with Realtek ethernet adapter. It says that the ethernet is "not managed". I tried modifying the managed=false to managed=true in /etc/NetworkManager/NetworkManager.conf but that didn't work. Can anybody help me?


There seems to be some sort of a network issue that is preventing Windows Update from downloading updates. The progress bar keeps on going forever.  I have done just about everything on the PC to make it work to no avail. This includes disabling firewalls and anti-virus software. According to this post which I believe sums up my situation there might be an issue with my Internet connection:    I am connected through a wireless Cisco router. Unfortunately I don't have access to another network. Neither do I have a network cable. But my Internet is working; I can download and upload files no problem.  The OS is not new but the user I'm logged in as is a new admin user.  How can I know what's wrong with my Internet connection, or more precisely what's blocking Windows Update?  P.S. One of the ideas I tried was upgrading the OS to Windows 10, but even the Windows 10 Installer gets stuck at the "Getting Updates" screen.  P.S. I am not able to connect my computers at home even though they are all in the same workgroup. The PC shows up as a shared computer on a Mac but is not connectable. All computers are connected wirelessly through the aforementioned router.


I'm learning jQuery by trying to understand other people's code.  I ran into this:  jQuery.fn.myFunc = function(options, callback) {  //stuff    jQuery(this)[settings.event](function(e) {     var self = this,     $self = jQuery( this ),     $body = jQuery( "body" );      //etc.   }  //more stuff  }   My understanding is that $ refers to the jQuery object.  So why put $ with $self and $body? And is self the same as $self?


How to copy only file attributes (metadata) without actual content of the file?

I've already copied terabytes of files with rsync but I forgot to use --archive to preserve files' special attributes.  I tried executing rsync again this time with --archive but it was way slower than what I expected. Is there any easy way to do this faster by just copying metadata recursively?


Key Derivation Functions vs. Password Hashing Schemes

Key derivation functions, such as HKDF (standardized in ), are meant to stretch some initial keying material having enough entropy, like a Diffie-Hellman shared value, into one or more strong cryptographic secret keys.   Password-hashing schemes, such as the  winner , are meant to hash usually low-entropy passwords with the goal of making the hash digest inversion as costly as possible for an adversary with respect to CPU and memory consumption, as well as parallelization.  Is it exact to consider that password-hashing schemes are actually key derivation functions specialized for low-entropy inputs? Or is there any other essential difference of theoretical nature between these two types of cryptographic schemes?


I've come across an exercise while preparing my OCA, i don't understand why the program print : abce 3 instead of abcde 3. Here the program :  'public static void main(String[] args) {         System.out.print("a");          try{             System.out.print("b");              throw new IllegalArgumentException();           }catch(IllegalArgumentException e){               System.out.print("c");               throw new RuntimeException("1");           }catch(RuntimeException e) {               System.out.print("d");               throw new RuntimeException("2");           }finally {             System.out.print("e");             throw new RuntimeException("3");           }         }'   Any explanations why it ignores the last catch block  will be really appreciated!


I am using TabLaout in Activity , but it showing NULL pointer

This is my code     package com.saverx.rushabh.saverx;  import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentPagerAdapter; import android.support.v4.view.ViewPager; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.os.Bundle; import android.support.design.widget.TabLayout; import android.view.ViewGroup;   public class MainActivity extends AppCompatActivity {       View view;     private static final String ARG_SECTION_NUMBER = "section_number";     ViewPager viewPager;     //TabLayout tabLayout;     TabLayout tabLayout;     LayoutInflater inflater;     ViewGroup container;     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          this.container=container;          this.inflater=inflater;         this.view= inflater.inflate(R.layout.activity_main, container, false);         viewPager=(ViewPager)view.findViewById(R.id.viewPager);         viewPager.setAdapter(new sliderAapter(getSupportFragmentManager()));         tabLayout=(TabLayout)view.findViewById(R.id.sliding_tab);         tabLayout.post(new Runnable() {             @Override             public void run() {                 tabLayout.setupWithViewPager(viewPager);             }         });                 //return view;     }      private class sliderAapter extends FragmentPagerAdapter {           public sliderAapter(FragmentManager supportFragmentManager) {             super(supportFragmentManager);         }          @Override         public Fragment getItem(int position) {             Log.e("adapter", ""+position);             //  return new CalendarFragment();             NewLeadsFragment obj= new NewLeadsFragment();           /*  Bundle bundle=new Bundle();             bundle.putInt("position",position);             obj.setArguments(bundle);             return obj;*/           return obj;          }          @Override         public int getCount() {             return 3;// 3 tabs         }           @Override         public CharSequence getPageTitle(int position) {             switch (position) {                 case 0:                     return "Leads";                 case 1:                     return "Meetings";                 case 2:                     return "Service";             }             return null;         }      }    }   Exception is     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.LayoutInflater.inflate(int, android.view.ViewGroup, boolean)' on a null object reference                                                        at com.saverx.rushabh.saverx.MainActivity.onCreate(MainActivity.java:33)   This code is working perfectly fine when I am using fragment instad of activity  I am using tablayout so that i can drag through signup and sign in using tablayout.  The runtime error is :  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.saverx.rushabh.saverx/com.saverx.rushabh.saverx.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.LayoutInflater.inflate(int, android.view.ViewGroup, boolean)' on a null object reference  I summarise that the error may be due to I havent inserted this.view=view but it is throwing same exception


My picture is missing on my profile page

The profile picture is missing on . The relevant part looks like    Since this profile picture appears almost everywhere when I am referenced, quite a few other pages looks buggy. For example,  , , , .  The url to my picture, which can be found by searching the source page is, . When I check that url directly, it does return "404. That’s an error."  As I would like to believe, http 404 should never be returned to a request for a profile picture, since the picture is either automatically generated or replaced by one selected or uploaded by the user.  I know there is simple workaround, I can edit my profile by changing my picture to an image I uploaded. However, I would like to raise this as a bug before doing that.   (Incidentally, I love my missing profile picture that was generated automatically, which looks like the following.)    This bug has been active for more than a week. I did not report it initially since it might be just a temporary glitch.  Apparently, the missing of profile picture happens to some other users, too. For example, .    Update:  Thanks to Discrete lizard's comment, now I see what is happening. When I registered my account on Computer Science Stack Exchange (CSSE) with my Gmail address, CSSE (or its mother engine at StackExchange) asked Gmail/Google for my avatar. Since I had never specified one for my Gmail/Google account, google had generated one for me, whose url was returned to and used by CSSE. However, I had only seen that avatar on CSSE, which caused me to believe that avatar was generated by CSSE. When Google updated the url for my avatar, which is the same as before a while ago to this new googleusercontent url, , the previous url saved by CSSE became invalid, causing the problem.   In light of above explanation, this broken profile picture can be considered a feature by design instead of bug of CSSE (or just StackExchange). Of course, some action could be taken by StackExchange to improve the situation as discussed by .  Depending on the situation, I might change the above update to an accepted answer so as to finish this question.


Is a Self-defining Table of Domains Normalized?

I don't really know the official name of what I've made but it can't be the first time this has been made, so apologizes up front for not knowing every term.  My question, is a table as outlined below normalized?  pk    fk    description 1     1     domains 2     1     people 3     1     cars 4     2     tom 5     2     smith 6     3     vmw 7     2     betty 8     3     ford   The main 'rule' this table confuses me about is A table should store only data for a single type of entity. It stores domain information, but it stores multiple domains' information.  A example use for this table, fetch the domain of people.  select * from domains where fk = 2   which returns  pk    fk    description 4     2     tom 5     2     smith 7     2     betty   The fk is the 'domain' the item is in, which is the pk of the domain. This is what to me is self-defining because this table defines which domains it contains.


I used the following to remove all mongodb packages so I can start fresh, but it does not seem to be working.  How can I totally remove mongodb?  I did:  sudo apt-get autoremove mongodb-* sudo apt-get purge mongodb mongodb-clients mongodb-server mongodb-dev   None of all that works.  When I do mongod --version I still get:  db version v2.6.10 2017-10-01T00:20:56.172-0400 git version: nogitversion 2017-10-01T00:20:56.172-0400 OpenSSL version: OpenSSL 1.0.2g  1 Mar 2016   When I run dpkg -S $(which mongod) I get the following:  mongodb-server: /usr/bin/mongod   The same for mongo.


Migration stats not consistent between sites

Apparently, as a result of  it appears that Yannis and myself see different statistics when going to the programmers.SE.com migration stats tool and the stackoverflow.com tool respectively.    :        while I see:        Why are the rejection rates so radically different?  Which is correct?  (Or am I simply misinterpreting the data somehow and these are representing different statistics)


Struggling to gain rep 'points' and unable to actually help the community

I'm trying to gain rep by adding to questions. Most of the questions I see have already been answered but adding to them as a comment would make the most sense as it's another added help.   Also, marking an answer as correct for me is annoying that I can't even do that and having a list of questions that I've searched for and found and answer would be helpful (this may already exist but I wouldn't know as I can't up-mark any correct/helpful answers).  I've asked questions on the forums but nobody can help with the ones I ask so again I'm stuck for gaining rep and getting answers. Whether I'm lower in the stack of viewable answers due to my rep I don't know?  Is there a simple way of gaining reps so I can fully contribute to Stack Overflow that I'm missing as a newbie?


Hey guys im new to Ubuntu so i installed Ubuntu 16.04 onto DOS OS of my HP.  Legacy support is Enabled.Security Boot Disabled in the BIOS Settings.  When i go to the additional driver i get nothing except the default Unknown one. The output i got after running iwconfig is eno1      no wireless extensions.  lo        no wireless extensions.  The ouput i got after running lspci -nn is 00:00.0 Host bridge [0600]: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers [8086:5914] (rev 08) 00:02.0 VGA compatible controller [0300]: Intel Corporation UHD Graphics 620 [8086:5917] (rev 07) 00:04.0 Signal processing controller [1180]: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem [8086:1903] (rev 08) 00:08.0 System peripheral [0880]: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th Gen Core Processor Gaussian Mixture Model [8086:1911] 00:14.0 USB controller [0c03]: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller [8086:9d2f] (rev 21) 00:14.2 Signal processing controller [1180]: Intel Corporation Sunrise Point-LP Thermal subsystem [8086:9d31] (rev 21) 00:16.0 Communication controller [0780]: Intel Corporation Sunrise Point-LP CSME HECI #1 [8086:9d3a] (rev 21) 00:17.0 SATA controller [0106]: Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode] [8086:9d03] (rev 21) 00:1c.0 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 [8086:9d14] (rev f1) 00:1c.5 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express Root Port #6 [8086:9d15] (rev f1) 00:1f.0 ISA bridge [0601]: Intel Corporation Device [8086:9d4e] (rev 21) 00:1f.2 Memory controller [0580]: Intel Corporation Sunrise Point-LP PMC [8086:9d21] (rev 21) 00:1f.3 Audio device [0403]: Intel Corporation Sunrise Point-LP HD Audio [8086:9d71] (rev 21) 00:1f.4 SMBus [0c05]: Intel Corporation Sunrise Point-LP SMBus [8086:9d23] (rev 21) 01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 15) 02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. Device [10ec:d723]  Output after running rfkill list all is 0: hci0: Bluetooth     Soft blocked: no     Hard blocked: no PLEASE HELP !


How to solve Operator '!=' cannot be applied to operands of type 'T' and 'T'

This code snippet works as expected for the int type:  public class Test  {     public int Value     {         get => _Value;         set         {             if (_Value != value)                 _Value = value;         }     }     private int _Value; }   When int is replaced by the generic T, the compiler complains with:     Operator '!=' cannot be applied to operands of type 'T' and 'T'   Why does this happen and is there a way to solve it?


I have a shell script ren.sh  #!/bin/bash /usr/bin/mv /home/imp/imp/msgs/$1.PK1 /home/imp/imp/msgs/$1.BRD /usr/bin/mv /home/imp/imp/msgs/$1.PK2 /home/imp/imp/msgs/$1.MIX   It works fine, but it only moves 2 files at a time (*.PK2 and *.PK1). I'd like for it to move all existing *.PK1 and *.PK2 files to *.MIXand *.BRD files  Is this possible?


Asymptotic behavior of the sequence $a_n=\sqrt{n+a_{n-1}}$

Let $a_1=1$,  $a_n=\sqrt{n+a_{n-1}}$, $n\geq 1$. Show that $a_n=\sqrt{n}+\frac{1}{2}+\frac{1}{8\sqrt{n}}+o(\frac{1}{\sqrt{n}})$.   How to prove, and is there any general method?


i want to get my div content with all its css styling as pdf file but when i click on button to get pdf it show only its html content not its css styling tere are my code of js and html    i do this work with jsPDF library       function Convert_Html() {         var doc = new jsPDF();         var elementHTML = $('#con').;         var specialElementHandlers = {             '#elementH': function (element, renderer) {                 return true;             }         };         doc.fromHTML(elementHTML, 15, 15, {             'width': 170,             'elementHandlers': specialElementHandlers         });         doc.save('id.pdf');     } </script>       my html code

                 @*

*@

Tony Stark

Strength: Ironman Suit

Weakness: None

Known as: Iron Man

 <button onclick="Convert_Html();">Get</button>      here i am getting problem it give only it html not all css


I am rather illiterate when it comes to mathematics, I am afraid. In an effort to change that, I grabbed a copy of 'What is mathematics? : An elementary approach to ideas and methods' and have already encountered some difficulty. It seems silly to waste so much time trying to solve it myself, so I decided to ask for some help in solving and illuminating the taken steps, so that I can solve some more on my own. I shall review some of the basics while awaiting answers, and hope that my session tomorrow shall be more productive...  The problem is as follows:  Prove by induction that $1^3 + 2^3 +3^3 ... n^3 = [ (n(n+1))/2 ]^2 $.  As is, at the point I decided to seek help and look up material for review, I have taken the following steps:  solved for the base case: n=1, $1^3 = [2/2]^2 $  $$ 1 = 1^2, 1=1 $$  Then after proving the basis, I stated the assumption that:  $1^3 + 2^3 ... k^3 = [ (k(k+1)) / 2 ]^2$ is true.  Then I tried to solve for the next case, $(k+1)^3$:    $$ 1^3 + 2^3 + 3^3 ... k^3 + (k+1)^3 = [ ( (k(k+1)) / 2 ) + (k+1) ]^2 $$  $$ [ (k(k+1)) / 2 ]^2  + (k+1)^3   =  [ (k(k+1) + 1(k+1) ) / 2 ]^2 $$  at this point after failing for a while and having spent quite some time looking up material, I sought help. I hope I'm going down the right path here, but I suspect I shall soon find out...   Help is greatly appreciated.


why isnt this working package com.company; import java.util.Scanner;  public class Main {    public static void main(String[] args) {   // write your code here     Scanner scan = new Scanner(System.in);     System.out.println("enter year: ");     int year = scan.nextInt();     int age = 0;     System.out.println("is your bday complete this year: ans 'Y/N'");     String bday= scan.nextLine();     scan.close();     if (bday=="Y"||bday=="y"){         age = 2021-year;     }else if(bday=="N"||bday=="n"){         age = 2020-year;     }else{         System.out.println("wrong input");     }     System.out.println(age);   } }


Prove for bounded $f$, if $f:[a,r] \to \mathbb{R}$ is Riemann-Integrable for $r \in [a,b)$ then $f:[a.b] \to \mathbb{R}$ is Riemann-Integrable and $\displaystyle \lim_{r \to b, r < b} \int_a^r f= \int_a^bf$.  Alternative definition for Riemann-Integrable functions :: $f : [a,b] \to \mathbb{R}$ is Riemann-Integrable if $\forall \varepsilon > 0, \exists$ step functions $f_\varepsilon, g_\varepsilon$ such that $\lvert f- f_\varepsilon \rvert \le g_\varepsilon$ and $Ig_\varepsilon \le \varepsilon$ where $Ig_\varepsilon = \sum_{j = 0}^{N}g_\varepsilon(x)(\Delta x_{j+1} - \Delta x_j)$.  $f$ is bounded so $\displaystyle \exists M \in \mathbb{R}^+$ s.t. $|f(x)| \le M, \forall x \in [a,b] $ so we know  $\displaystyle|\int_a^r f| \le \int_a^r|f| \le M(r-a) \le M(b-a) $. Now, for some index set $I$ where $r_0 \le r_1 \le \ldots\le r $ we have $\displaystyle \int_a^rf = \sum_{i \in I}\int_{a}^{r_{i}}f$  Do I need to show $f$ is Riemann-Integrable over $[a,b]$ before I can solve the limit? It seems like it but seems like the other way would give it to me.  EDIT:  Since $f(x) \le M, \forall x \in [a,b]$ and we have there exists $r \in [a,b]$ such that $b - \frac{1}{n+1} < r < b$ we have $\displaystyle \int_a^{b-\frac{1}{n+1}}|f| \le \int_a^r|f| \le M(b-a)$ Does this give me that $f$ is Riemann-Integrable over $[a,b]$?


What is meant by the notation “a polynomial $p(x_1, ..., x_n)$”?

Can someone please explain (with an example or two) what is meant by “a polynomial $p(x_1, ..., x_n)$”? Stillwell starts referring to them without defining them and they are beyond my elementary mathematics education. He usually adds “with integer coefficients.”


How to show the loading indicator in the top status bar

I have noticed that some apps like Safari and Mail show a loading indicator in the status bar (the bar at the very top of the phone) when they are accessing the network. Is there a way to do the same thing in SDK apps, or is this an Apple only thing?


How to fix this Minecraft 1.7.10 server error?

I've been having a problem with this one error when I try to log onto a server, and I've looked for answers but haven't found any. What causes the error and how to fix it?     Internal Exception: java.io.IOException: An existing connection was forcibly closed by the remote host


What happens on the NYSE during an IPO such that the first trade may be hours after the opening bell?

So, I understand that today's Spotify IPO isn't a traditional IPO. But I think my question extends beyond this. At about 12:45pm today, shares of Spotify finally started trading on NYSE. Opening bell was 9:30am though, and I thought that was the "real" open. What was happening before the first trade, in terms of stock exchange mechanics? Alibaba in 2014 did a regular IPO and also didn't trade until almost 12:00pm on its opening day.  Update: Following some WSJ live updates, it seems like they were waiting for the spread to narrow before trading would begin:  The price range of Spotify’s first trade has just narrowed to $167 to $170, a sign that the opening could be drawing closer. The range has moved up a few times, illustrating investor demand. ― Alexander Osipovich  What I don't understand is whether the exchange has put a barrier in place (e.g. like a pre-open or delayed-open state where only passive, liquidity-providing orders are allowed), or traders are choosing not to trade for whatever market reasons. I thought it had to be the former, but then this update makes it sound like the first trade was not a scheduled event:  Shouts and applause broke out on the floor of the New York Stock Exchange as Spotify shares started trading at $165.90. A total of 5.6 million shares changed hands in the first trade. ― Alexander Osipovich


SVM: Why does the number of support vectors decrease when C is increased?

I am learning how to use libsvm through sklearn.svm in python. I read  about what happens and why when you change the C value as part of your model. My intuition from what I've learned would be that lower C values would use less support vectors to make a more general classification, while higher C values would use more support vectors to attempt to 'overfit' and account for all outliers.   That is not the case. For an example where I looped through a set of C values like so:  print(c) model = svm.SVC(kernel='linear', C=c) model.fit(Xtrain, ytrain) print("support vectors:", len(model.support_))   I got results:  1.0 support vectors: 1810 10.0 support vectors: 1750 100.0 support vectors: 1626 1000.0 support vectors: 1558   As you can see, as C goes up, the number of support vectors used in the model goes down. Why does this happen?


How to find all irreducible polynomials in Z2 with degree 5?

I am totally lost on how to do this one. I am supposed to accomplish the following:  Find all irreducible polynomials in $\mathbb{Z}_2[x]$ with degree $5$.  I may use the fact that x, $x+1$ and $x^2+x+1$ are the irreducibles of degree less than or equal to 2  If someone could provide a step by step explanation of how to do this, that would be amazing! Thanks in advance!  P.S.: This is not a homework, but is a question on a past exam that I couldn't answer and I want to know how to do it.


Why is it happening? How can I get rid of this?


Thunderbird complains about this error. It's happened for two consecutive updates. Is this a fault with Thunderbird or the mail server?      Timestamp: 8/19/2015 3:54:37 PM   Error: uncaught exception: 2147746065      Timestamp: 8/19/2015 3:54:37 PM   Error: mail.spamarrest.com : server does not support RFC 5746, see CVE-2009-3555


Microkernel (e.g. GNU Hurd) more secure than monolithic kernel (Linux)?

I would like to understand (in relatively layman's terms) if and how a microkernel such as the -based  is more secure than a monolithic kernel such a .  Additionally, does a micro-kernel affect network security differently form a monolithic kernel?


Evaluate $ \int {(\tan x)}^{\frac{1}{3}} dx $

Evaluate the following indefinite integral. $$ \int {(\tan x)}^{\frac{1}{3}} dx $$ How could i do this integral ?  I tried multiplying the numerator by ${(\sec x)}^2$ and denominator by $1+{(\tan x)}^2$ but getting stuck after putting $\tan x=t$.


In The Walking Dead, if everyone is infected, why are the zombies trying to eat them and not other zombies?

If everyone is infected, why are the zombies trying to eat them and not other zombies?


I have Windows 10 as host O/S and Redhat-7 as guest O/S. Everything was working fine but one day I face error Network Error: Software caused connection abort. I have used bridged mode for the guest OS in VMware Workstation. I search with google spending around 3-4 hours but every solution provided and I got was bootless. For resolution, I again readded new ethernet but the problem still persists. I have exactly the same problem in link  . I think of reinstalling the new O/S, but same error occurred with the newly installed O/S too. So any help from experts is highly appreciated.


! Undefined control sequence. \Ginclude@graphics ...\Ginput@path \set@curr@file {#1}\edef \uq@curr@file {\

what mean this error and what should i do to solve it please help me  (! Undefined control sequence. \Ginclude@graphics ...\Ginput@path \set@curr@file {#1}\edef \uq@curr@file {...)


Virtual, Override and new keys in inheritance hierarchy

I have the following code:    class Animal     {         public virtual void Invoke()         {             Console.WriteLine("Animal");         }     }     class Dog : Animal     {         public override void Invoke()         {             Console.WriteLine("Dog");         }     }     class Dobberman : Dog     {         public new void Invoke()         {             Console.WriteLine("Dobberman");         }     }      class Program     {         static void Main(string[] args)         {             Animal dog = new Dobberman();             dog.Invoke();             Dobberman dog2 = new Dobberman();             dog2.Invoke();         }     }   Why would it print "Dog" in the first output? and why "Dobberman" in the second? What is going on under the hood?


For example we have $\frac{0}{0}$ which is undefined or we have a multiplication of $2\times2$ and $3\times3$ matrices which is also undefined. Is there any symbol for representing it?


Completing the square to find the Fourier transform of a Gaussian

I'm trying to find the Fourier Transform of a Gaussian, and I end up having to complete the square in the argument of an exponential so I can use the standard Gaussian integral. I basically have:  $$\bar f(k) = \int_{-\infty}^{\infty}e^{\frac{(x-c)^2}{a^2}-ikx}dx$$  And I have trouble finding the polynomial I need. I end up doing something like:  We require a function of the form $(\frac{x-c}{a} + A)^2$ such that  $$-2c+2Aa = ikx$$  as I believe  $(\frac{x-c}{a} + A)^2 = (x + (-c + Aa))^2$ should be equivalent?  $$\implies A = \frac{ikx + 2c}{2a}$$  However, this doesn't solve the problem. I need $A$ to not be a function of $x$. How should I instead approach this?


Maximum number of Upvotes in a day in Stackoverflow

I know that it is 40 Upvotes per day but i have got 42 today,     How is this possible?? Why does this happened. Please explain.


What WordPress API function lists active/inactive plugins?

After seeing thousands of useful API functions in the WordPress core, I'm surprised to discover today that there ain't a function that would list the active plug-ins. I don't know you but I'm quite surprised at that.   I was wondering if there is a reason for missing that?  If so, I'd like to know about it.   And, if there is a quick PHP snippet you know of that could give you a list of active plugins, ( the same way that a get_post_types('','names'); does for CPT's or get_taxonomies('','names'); does for CTs ), I'd appreciate it if you provide the code.


PCA is an autoencoder with linear transfer functions

As the title states: PCA is an autoencoder with one hidden layer with linear transfer functions.  Can someone explain this sentence to me? I understand that if you want to map something into lower dimensional space then PCA has essentially perfectly optimized this procedure. With this understanding, if an autoencoder has a loss function that aims to find the best representation in lower dimensional space (say dimension H) then PCA that takes H rank basis vectors will produce the exact same result as the autoencoder?   Which of these is quicker and a better approach?


Check linear and differential cryptanalysis of a new block cipher

I am developing a new block cipher primitive. I would like to test its robustness against attacks of linear and differential cryptanalysis. Is there a tool to evaluate this using only plaintext and ciphertext?


Associating two children to one parent in Forest

I am trying to draw a nice multi-dominance. I find the gap between the two lines above "V" is ugly. Is there any way to move the lower end of the line in red square so that the two lines meet at one point right north of "V"?   Thank you very much.  \documentclass{article} \usepackage{forest}  \begin{document} \begin{forest} where n children=0{tier=CV}{}     [\sg     [C, tier=CV]     [\mo[, tier=CV, no edge][V, name=V, tier=CV]]     [\mo, name=mo[, no edge, tier=CV]]]     \draw (mo)--(V); \end{forest}  \end{document}


What to do after you lost restriction code on the iPad?

I guess the title says it all. I've the restriction code long time ago, and when I wanted to do actuall in-app purchase it turned out I cannot recall the password. Worse, now after 10 tries I have to wait 60 minutes before each consecutive tries.  The threads on forums are somehow misleading. Some of them claim the only way is to do fresh install and recover all the stuph manually. Some other people post some not entirely clear solutions involving restore from backup. Closest I got was the iPhoneBackupExtractor tool, which is suppose to read the plain text key code from the iPad backup. It worked to the point of getting hands on com.apple.springboard.plist. Unfortunately the password is not in this file.  Please keep in mind, this is about the "restriction code", not the main lock code. iPad if fully functional and the one feature blocked is in-app purchase.


base64_encoding of an md5 string - php vs javascript problem

I have an issue with an API that requires me to run a BASE64 and MD5 of a string. While a JAVASCRIPT code I created works well with this API, I need it in PHP, and I get the worng answer.   While testing the issue, I came to a conclusion that the issue is with the way the base64_encode function works in PHP, differs, and that creates the problem. I am attaching a code that will demostrate it  var CryptoJS = require("crypto-js"); var testStr = 'hello world!'; console.log(String(CryptoJS.SHA256(testStr))); # outputs 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9 console.log(CryptoJS.enc.Base64.stringify( CryptoJS.SHA256(testStr) )); # outputs dQnlvaDHYtK6x/kNdYtbImP6Acy8VCq1498WO+CObKk=   <?php $testStr = 'hello world!'; echo hash('sha256', $testStr); # outputs 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9 echo '<br />'; echo base64_encode(hash('sha256', $testStr)); # outputs NzUwOWU1YmRhMGM3NjJkMmJhYzdmOTBkNzU4YjViMjI2M2ZhMDFjY2JjNTQyYWI1ZTNkZjE2M2JlMDhlNmNhOQ==   I need the PHP code to output the same BASE64 result as the JS code. Can you please clarify what I'm doing wrong, and how can I fix it?


Integral of 1/x- why does it behave this way?

First of all, I'm not entirely sure what to call polynomial functions that can have x raised to negative integers powers, so I will just call them polynomial type functions.  The integral of every polynomial type function is another polynomial type function, unless, of course, our polynomial type function has $\frac{1}{x}$ in it. In that case, our integral is obviously $\ln{x}$.  In the case of every other function in the form $x^{k}$ for some integer $k$, we can use power rule to find the integral. With $\frac{1}{x}$, there is a problem, since our integral will have had a constant of $0$ multiplying the term, nullifying it.  So my question is, why does it happen to be true that every single polynomial type function has a polynomial type integral, except $\frac{1}{x}$? $\frac{1}{x}$ happens to be the only function where using power rule to evaluate the integral doesn't work, and it also happens to the be the only one without a polynomial type integral.  This can't be a coincidence: the two special properties of $\frac{1}{x}$ must be related. What about $\frac{1}{x}$ makes it so special?


Textbook on Graph Theory using Linear Algebra

Is there any undergraduate textbook on graph theory using linear algebra? A request is a beginning with graph matrices that explain most concepts in graph theory?   P.s. This thread has more specific requests than this thread .


Community rejects edit with incorrect reason

Community properly rejected  due to edit conflict. The rejection was triggered by  by the author.   However, the review message by Community is      This edit did not correct critical issues with the post - view the revision history to see what should have been changed.   This message would imply a reviewer rejected my edit, but it can be seen this is not the case. No one reviewed the edit as "Reject and Edit", and the rejection took place at the exact same time the author made the edit above.  According to , the expected message would be      This edit conflicted with a subsequent edit.


Why or how did Smeagol's "name" became Gollum?

The corrupting effects of the One Ring on the hobbit Sméagol are well-known: when his relative Déagol found the Ring, Sméagol became instantly affected by its influence and strangled Déagol when he refused to hand over the Ring. The One Ring changed Sméagol into a grotesque creature that lived in the darkness and shadows of goblin tunnels and caves; and fed on stray goblins / fishes or basically whatever squiggly stuff that could be found. The ring also gave him unnaturally long life span and a personality like a crazy road lizard.  But how did Sméagol's name become Gollum? Why did people start to address him as Gollum? Was the name an inherent alter-ego that came with the ring? Did someone name him Gollum?


If $f$ is the quotient mapping, is $(Y,\tau_1)$ metrizable?

Exercise: Let $(X,\tau)$ and $(Y,\tau_1)$ be topological spaces and $f:(X,\tau)\to(Y,\tau_1)$ a quotient mapping. If $(X,\tau)$ is metrizable, is $(Y,\tau_1)$ metrizable?   Attempted solution:     Lemma: A metrizable space is Hausdorff.   If I assume $(X,\tau)$ to be a discrete space and $(Y,\tau_1)$to be a topological space endowed with the cofinite topology.  $(Y,\tau_1)$ is not Hausdorff.  Now I need to check if $f$ defines the quotient topology $\tau_1$. If $\{y\}\in Y$ then it is closed so $f^{-1}({y})$ is closed then ${Y}$ is closed in the quotient topology such as the union of all singular points, then $\tau_1$ is the cofinite topology.  Question:  Is this proof right? If not? Why not? What are the alternatives?  Thanks in advance!


Print category codes of all 256 possible input bytes?

The title.  Is there a way to print (to the log file) the category code of every single possible input byte, either in order, or in some tabular form?


How can I show random IDs to a Google form respondents?

I want to collect contact details for invitees using a Google form created for this purpose. I want the respondents who give me their contact details to also input an appointment entry in a public calendar. To maintain their privacy, I should not ask their names in the public calendar. I need them to input their unique ID so I can link their calendar's entry with their form contact details. I need a public calendar so they do not pick a conflicting data taken by another respondent. Is there any way to show a random ID for a Google form respondents? If not, are there any suggestions to link public calendar entries with contact details to contact the person?


Partial order is intersection of linear extensions also if poset is infinite?

I cannot understand the statement "every partial order is the intersection of its linear extensions. (See e.g. Davey and Priestley [DP]" . The book Introduction to Lattices and Order on page 32 assumes that $P$ is finite, not infinite. So suppose that the poset $P$ is infinite.   Is the intersection of linear extensions now the infinite $P$?


How to add tags to files in Windows 7 so that they appear in search results

In Windows 7, I want to add tags to my files (PDF, Word, Images etc) so that they appear directly in the search results, regardless of their content, title etc.    shows how to search by tag, but it does not tell how to add a tag in any file.  In the long term, I'm planning to add such tags programmatically as well.


What are the orbits of satellites; circular or elliptical?


Why did my $2.5 USO1 Call option increase in value today?

Today 4/30/20 my seemingly worthless USO call option increased in value.   Specifically: USO1 $2.5 Call 5/8  On 4/29 it was valued at $.04 and stayed there.   4/30 I checked after hours and now it’s up to $.08? Which was wasn’t even the highest it went to today.  So who is buying this contract?  Who is allowed to buy this contract? Bc I’m only able to sell and from what I understood, nobody is able to buy it.   I have screenshots and will post if requested. Thank you


Order of $xy$ when $\gcd(o(x), o(y)) = 1.$

I'm currently working on a problem where I have to find the order of xy in an abelian (not necessarily finite) group $G$, where I know that $o(x)=n$ and $o(y)=m$ are finite, and that $\gcd(n, m) = 1$. The proof I currently have is the following: Because the $\gcd$ of $n$ and $m$ is equal to $1$, we know that $\text{lcm}(n, m) = nm$. From this, we know that there does not exists $a \leq nm$ such that $n | a$ and $m | a$. Because of this, $nm$ is the first value in $\mathbb{N}$ for which $x^{nm} = e$ and $y^{nm} = e$, so $(xy)^{nm} = x^{nm} \cdot y^{nm} = e^m \cdot e^n = e$. By the definition of the order, nm has to be the order of $xy$. I know that my proof is wrong somewhere, but I can't really seem to find the problem, could anyone maybe help me? Thanks in advance!


Why does Firefox use the "chrome://" protocol / schema in URLs?

When I want to configure an addon, for example Ghostery, the tab shows a URL like this one:     chrome://ghostery/content/options.html   What does it mean? Does it have something to do with the Chrome browser?


On-board keyboard and trackpad not working 20.04

I'm on an Acer Aspire E5 and I haven't been able to get my laptop's onboard keyboard and trackpad to work, although the trackpad is detected as a Synaptics, and the keyboard is showing as an AT Translated Set 2 keyboard. External mouse and keyboard works fine, and are what I am currently using. I already checked whether I'm on Synaptics or Libinput, although I was fairly certain that upgrade happened a few years ago, and I am definitely using libinput, which I reinstalled, to no avail. I've made sure that the trackpad is enabled in the system settings, and I've switched it from advanced mode to basic in the BIOS, which for some seemed to have been the solution I'd like to note that the onboard keyboard works fine on boot, and its only when X is loaded (i'm assuming) that it fails. I have just recently installed Kubuntu on this machine after grappling with the same issue on Arch, thinking i had done something wrong in the installation. On Arch, I had no trouble using the keyboard on the TTY and live-USB (Arch and Ubuntu), but when i installed X for a GUI, they both stopped working. What should my next steps be?


Show that the centre of the circle $\dots$ approaches the point $\epsilon(s_0) = \dots$ - Elem Diff Geo Pressley

Help on getting started with this exercise    Another approach to the curvature of a unit-speed plane curve $\gamma$ at a point $\gamma(s_0)$ is to look for the `best approximating circle' at this point. We can then define the curvature of $\gamma$ to be the reciprocal of the radius of this circle.  Carry out this programme by showing that the centre of the circle which passes through three nearby points $\gamma(s_0)$ and $\gamma(s_0 \pm \delta s)$ on $\gamma$ approaches the point $$\boldsymbol \epsilon(s_0) = \gamma(s_0) + \frac{1}{\kappa_s(s_0)} \mathbf n_s(s_0)$$ as $\delta$s tends to zero. The circle $\mathcal C$ with centre $\epsilon(s_0)$ passing through $\gamma(s_0)$ is called the osculating circle to $\gamma$ at the point $\gamma(s_0)$, and $\boldsymbol \epsilon(s_0)$ is called the centre of curvature of $\gamma$ at $\gamma(s_0)$. The radius of $\mathcal C$ is $1/|\kappa_s(s_0)| = 1/\kappa(s_0)$, where $\kappa$ is the curvature of $\gamma$ $-$ this is called the radius of curvature of $\gamma$ at $\gamma(s_0)$.


Does an Obj important contain UV mapped textures?

I am almost a total beginner with blender. I purchased a model off of . which came with a .obj file, a .mb files and some .jpg textures. On the website it says its already been fully textured and UVmapped. But when I import the .obj into blender, it does not appear to have any textures applied (and when I switch to rendered view it's just black).   I also tried loading the .mb file into maya and I see this green blob, though it does appear to contain textures and material properties.    Given what you see, does the .obj file not have textures and is there no way to work with in blender?


Are colors grounded in physics or are they a matter of human perception?

My father was colorblind, and I always wondered if colors were a matter of physics or if different colors are just a human way of describing and differentiating our visual perception of the world?  For example, is the color blue by nature blue, or is it just what we see?


How long does a one-round spell last? Would it be start of the caster’s next turn, the end of the caster‘s next turn, or somewhere in between?

While I expect the quick answer to be “One round is one round or one round is six seconds?” I don’t think that ‘in game’ that is really true.  There are a number of one-round effects that last for more or less than one round.  So how long does that one-round effect last?  For example: color spray states:     each creature affected by this spell is blinded until the spell ends   So when would the blinded creatures see again?


Time to allow suggested edit on per site metas?

So I was just answering a question on Ask Ubuntu meta about code formatting and it was brought to my attention that users under 2k cannot even click the edit button to view the formatting. Looking around I think this was done because metas are low traffic and they didn't want the queue to fill up with suggestions that may never be reviewed and that makes sense. Now though many metas are quite healthy and have dedicated user bases that would review these edits. My suggestion is to lets sites choose to allow suggested edits on metas or not based on their needs. A site like Ask Ubuntu could benefit from this as we have a few users who are quite dedicated but fall below the 2k threshold for whatever reason. Letting them suggest edits could only be a benefit to the site as I see it. This seemed a popular request back a few years but nothing seems to of came of it. Related:


In VirtualBox can't get max display resolution for guest OS

I'm using VirtualBox with Windows 7 as the guest OS. However the max resolution setting I can get in the control panel is only 1264x602. How can I get up to the full HD resolution that I have in the Windows 7 host?


When do we use " public class Something { " vs " class Something { "

for example,  1.  public class Something {      public static void main(String[] args){         System.out.print("Hello World");       } }   2.  class Something {       public static void main(String[] args) {          System.out.print("Hello World");        }      }


Minimize $\int\limits _{0}^{1} f^2(x) dx$ if $\int\limits_{0}^{1} f(x) dx = 1$, $\int\limits_{0}^{1} xf(x)dx = 1$

Any hints? Using integration by parts didn't produce any result. Interestingly, I cannot find any function $f(x)$ which such a property.


How to stick a curve (with shape keys) on rig?

I used curves to do my character's eyebrows and gave them some shape keys. But I didn't know that I coudln't give them an armature (the one for the character). Is there a way to keep the shape keys and making the curves followings the rig?


Is it stylistically correct to use "me" after an adjective ? Like "Intelligent me"

I am a non-native speaker and I was just wondering whether it is stylistically and grammatically correct to write something like  "smart me made the same mistake again" or "Intelligent me could not solve the riddle"  is this similar to saying "fifteen-year-old me?" Can I say "my smart self" instead ?


Wind Field freeze at frame 250. Where can it be changed?

I have setup a project of 250 frames with a flag and a wind force field. It works fine until I change the length of the project to 520 frames, then the flag is frozen after frame 250. There must be a simple way to change this. Thanks for any help. Regards, Daniel.


the shift key in my keyboard has stopped working.(mechanical problem) so, is there a way so that I can make windows think like (caps-button) is new shift button. I'll buy a new keyboard ASAP but I need to do some urgent work that's why.


Finding sum of ratio of binomial coefficients

Find a closed form for $$\sum_{k=0}^{k=1000} \frac{\binom{1000}{i}}{\binom{2000}{i}}$$   My attempt: First I used the definition of binomial coefficients(*) to expand out the quantity being summed over as shown below: $$ \frac{\binom{1000}{i}}{\binom{2000}{i}} = \frac{\frac{1000!}{i!(1000-i)!}}{\frac{2000!}{i!(2000-i)!}} = \frac{1000!}{2000!} \frac{(1000+i)!}{i!}$$ Now, I sum this quantity over 'i' which gives me the following: $$ \frac{1000!}{2000!} \sum_{k=0}^{k=1000}  \frac{(1000+i)!}{i!}$$ Now I'm not sure how to proceed...  Footnotes: $$*: \binom{n}{k} =  \frac{n!}{(n-k)!k!}$$


keyword rankings being disappeared from SERP?

We would great appreciate if someone can help us out there to solve the issue that we are experiencing in regards to keyword rankings being disappeared from SERP. It’s been a month since we are struggling to find a reason/solution for this unexpected scenario. The keywords and sites were on 1st page for almost 6 to 7 years and we have always maintained our positions. Below are the impacted websites and keywords •     •     •     Effected Keywords •    dinner cruise Sydney •    sydney harbour dinner cruise •    Sydney dinner cruise •    sydney harbour cruise dinner •    dinner cruise sydney harbour •    harbour cruise dinner For the above set of keywords, all these brand websites were ranking on the first page, however all of a sudden it’s nowhere on the first 10 pages and technically vanished from the SERP. We have done multiple on page & off page analysis to check and ensure whether we had any spamming issues. Under this assumption we even checked whether the site being penalized. Unfortunately the end result of all our analysis did not triggered any sign of errors or warnings. And all of the above sites are being framed based on Google guidelines and criteria’s. These pages will rank if we add a USP along with the above set of keywords. We had kept a tab on search console to check if we have any warnings or manual actions which is again NIL so far. Unbelievably all these keywords are showing impressions and clicks on our search console. How could that be! When these keywords are being wiped-out from SERP . Our Observations  We noticed constant fluctuations in SERP other than the first 2 results, major fluctuations on SERP being happening! Even in that case why have our sites been effected is a mystery!  Currently for any of our keywords only one of our brands are ranking and that keeps on switching between our brands when searched after an interval. This was not the case before, for any of our keywords, all 3 brands use to show up in 1st page. Why, we are still not sure since it was not the case for the past 8 to 10 years  All of these websites are being hosted in the same server and this has not changed since these sites hosted for the first time  There was no major or minor changes happened on any of these sites to trigger such an impact   We would appreciate if someone can help us find the reason of this issue and solve this at the earliest. Our business is badly impacted due to this, since 85% of the traffic is from these above sites. We are eagerly waiting for any sort of response for our concern!


A new release of Ubuntu brought a new mouse settings window. However, it only lists a sensitivity setting, no acceleration. Where is the setting for acceleration? How do I disable it?  If I disable acceleration using xinput (e.g. xinput --set-prop 15 270 1, which sets the acceleration multiplier to 1) it returns if I disconnect and reconnect my mouse, and also if I reboot. Any way around this?


Direct Object or Complement or Something else

She failed to respond. She wanted to smile. She decided to return. She preferred to travel by train. She managed to save a little money.   Are the infinitival clauses complements or direct objects in these sentences? Are they complements in the last two sentences and direct objects in others?


Why is Stack Overflow so strict regarding comments, votes, or other feedback from newer users?

I know this is a terrible way to start a presence on a new community forum, but frankly, I'm frustrated that Stack Overflow is so restrictive regarding the ability to comment or vote on the feedback of others.  New users need 50 reputation points to comment on a thread, and 15 reputation points to 'vote' up or down a response to a topic. It is a bit ridiculous when considering how unfriendly this approach is for newer users. You're basically denying users any ability to participate on your forums until they've created several help topics.  I don't want to create new threads, as I'm doing now, for issues that many others have discovered and provided insight toward. I'd prefer to vote up or down comments that I found helpful, or provide my own related feedback or questions.  Overall, I find this a terribly unfriendly approach for reaching out to a community of developers. You should be mindful of the newer members who ACTUALLY want to become an active part of the Stack Overflow community. Sure, you're concerned some 'bot' will spam your forums with nonsense, or a n00b will ask dumb questions. But there are better ways to handle those problems than denying everyone the ability to participate in your forums until you've decided they are privileged enough.  I digress. My initial inquiries and issues regarding JQuery functionality were acknowledged and resolved in another topic; I was unable to participate in or thank the authors for their helpful responses likewise.


How do I theme the Nautilus background image?

I want to change the background image in the Nautilus file browser. My idea is to put my own style in the background. I'm using Ubuntu 11.10 and Nautilus is version 3.  I know that I have to change the nautilus.css file of the theme, but the problem is that there is not a parameter for the background. I just want to apply an image but I can't find the file or parameter to change it.  The CSS file is in the directory /home/UserName/.theme/MyTheme/gtk-3.0/apps. I've changed the nautilus.css file. I wrote two new lines using CSS style but I don't know where the correct place is to put it. The lines are:   background-image: url("carbon.jpg"); background-repeat: repeat;   Obviously I put the image called carbon.jpg in the same directory of nautilus.css, but this change doesn't work because I need to know whichs class displays the Nautilus file browsing frame. If I find this class I guess that this code will work.  If someone knows how to do it, please tell me because I really want to make this change.


How start Xpad and viber minimised in the system tray when OS start. 14.04

after this  Code:  sudo apt-add-repository ppa:gurqn/systray-trusty sudo apt-get update sudo apt-get upgrade   i have system tray in 14.04 LTS.  Skype have menu item - "Start Skype minimised in the system tray" and it's work prefect. But viber and xpad don't have this.   I install alltray. But it don't work. I can't launch viber with alltray options becouse command to start look like  /opt/viber/Viber   xpad start minimised but in tray i have two icon's and they buggy.


Can I declare a class in a CIL dll file that doesn't inherit from object?

My friend and I are doing a project in which we will be needing a base-class that is not System.Object, as well as to create other classes that derive from that class and do not implement System.Object either. Can this be done (perhaps in pure CIL)? If the base-class can be defined in CIL, can the other classes be defined in c#? Thanks!


How to find the numerical value of $\tan20\tan40\tan60\tan80$?

$$\tan20\tan40\tan60\tan80$$  I tried to bring $\tan20$, $\tan40$ in $\tan(a+b)$ form but couldn't get the answer. Using calculator I got it has $3$. Can anybody please tell me how to solve this?


Using possessive apostrophes after users' names

In this post I posted comment in response to another. In the post, I tagged someone's username, but in its possessive form. I put a space in between the username and the apostrophe, because I wasn't sure if the username tag would disappear if an apostrophe and an s was added.   I know this is a tiny problem, that can easily be avoided, but I'd like to know. Are there algorithms in place that keeps the tag in place even though an apostrophe and an s is added?


Where to post a question about Algorithm-Copyright?

I posted a question (which is deleted now) on Stack Overflow, but it got closed as off-topic, but nobody answered my comment about the appropriate Stack Exchange site.  Where should I post a question about the copyright/license of a random number generator?


Google Chrome Not updating (Do not want to re-install or disturb apt)

Hello so I got a notification from sofware updater to update google chrome but it said Failed to  download packages pleases check your internet connection but I was connected to the internet already and installing any other packages would be intalled easily. Here is the code from terminal: Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done The following packages will be upgraded:   google-chrome-stable 1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 75.8 MB of archives. After this operation, 55.3 kB disk space will be freed. Do you want to continue? [Y/n] y Get:1 http://dl.google.com/linux/chrome/deb stable/main amd64 google-chrome-stable amd64 89.0.4389.90-1 [75.8 MB] 42% [1 google-chrome-stable 39.6 MB/75.8 MB 52%]                  3,6248% [1 gooErr:1 http://dl.google.com/linux/chrome/deb stable/main amd64 google-chrome-stable amd64 89.0.4389.90-1   Hash Sum mismatch   Hashes of expected file:    - SHA256:f38a1699e1707dd76edadc671d54922992ea4fd2705d79645679a6abe3e9f7c1    - SHA1:fc795cf3607888405e36b61230019d6dcff508db [weak]    - MD5Sum:58c8bec946f3251a13cdb5b56aecd0bd [weak]    - Filesize:75841728 [weak]   Hashes of received file:    - SHA256:09f32fa3eebfe13f3d1d5ca981260e7c8015cb074d61ad95fddb8810b3df095c    - SHA1:c3856406fc05efa2e87959b67c3f1f866d0362c1 [weak]    - MD5Sum:c5fa4ed66c5980d8982561c68dc06881 [weak]    - Filesize:75841728 [weak]   Last modification reported: Fri, 12 Mar 2021 00:18:53 +0000 Fetched 75.8 MB in 23s (3,341 kB/s)                                             E: Failed to fetch http://dl.google.com/linux/chrome/deb/pool/main/g/google-chrome-stable/google-chrome-stable_89.0.4389.90-1_amd64.deb  Hash Sum mismatch    Hashes of expected file:     - SHA256:f38a1699e1707dd76edadc671d54922992ea4fd2705d79645679a6abe3e9f7c1     - SHA1:fc795cf3607888405e36b61230019d6dcff508db [weak]     - MD5Sum:58c8bec946f3251a13cdb5b56aecd0bd [weak]     - Filesize:75841728 [weak]    Hashes of received file:     - SHA256:09f32fa3eebfe13f3d1d5ca981260e7c8015cb074d61ad95fddb8810b3df095c     - SHA1:c3856406fc05efa2e87959b67c3f1f866d0362c1 [weak]     - MD5Sum:c5fa4ed66c5980d8982561c68dc06881 [weak]     - Filesize:75841728 [weak]    Last modification reported: Fri, 12 Mar 2021 00:18:53 +0000 E: Unable to fetch some archives, try running apt-get update or apt-get --fix-missing.  I have tried everything that the terminal gave me but nothing worked. Anyways Here is the video evidence of it from the software updater:


Number of binary trees of specific height (h)

I am having trouble figuring out how to find the number of possible binary trees that can be formed that has height (h).  I know from notes and other similar questions here regarding the number of nodes and using Catalan numbers to figure out possible combinations but what about starting off with a specific height and figuring out the number of binary trees that can be constructed?  It does not have to be a full binary tree. Just a binary tree that can have either left or right or both nodes.


Age replacement policy for hard disks and SSDs at servers

I'm planing an age replacement policy for our storage and servers. Most of them are for DBs and some for images (static content) so yes, they have an huge I/O everytime.  Also, we use Samsung 840 Pro SSDs for the RAID Controllers (PERC H700i) as CacheCade.  Are you guys managing the replacement of old hard drives and solid state drives?


How to identify floats that are not referenced in text

I would like to ensure that all figures in my document are referenced somewhere in the text.  With all the editing I've been doing, some of the figures are no longer being referenced and I would like to find out which (so I can either delete the figures or add appropriate references).  Is there a way (using a package, or custom function) to highlight or list any floats that do not have a corresponding \ref{fig:foobar} in the text body?  Example:  \documentclass{article} \usepackage{graphicx} \usepackage{flafter} \begin{document}  There's a lady who's sure all that glitters is gold (See Figure \ref{fig:gold}). And she's buying a stairway to heaven.  \begin{figure}[] \includegraphics{gold.png} \caption{Picture of gold} \label{fig:gold} \end{figure}  \begin{figure}[] \includegraphics{silver.png} \caption{Picture of silver} \label{fig:silver} \end{figure}  \end{document}   I'd like to run a function that tells me fig:silver was never referenced in the text  Note that I'm already using flafter to ensure floats only appear after they have been referenced.  Is there an argument I can pass to flafter or \listoffigures which has the functionality I'm looking for?


Gridding or interpolating elevation data?

I wonder if someone can recommend a method for gridding elevation data in QGIS, GRASS or similar?   The elevation data I have is collected along 1m spaced lines at approximately 1 reading per second. So far I've tried inverse distance weighted, bicubic spline, and triangulation methods for the elevation data but all these produce a striping effect in the direction which the data is collected. I am not entirely sure that the error is due to the methods of gridding/interpolation I have been using. However, in tandem with the elevation data I am collecting a series of magnetic measurements (higher density), and these show no linear striping.


Starup disc creator software freezing up

I bought Ubuntu 19.10 from Ebay on a dvd and installed it that way, but have been having numerous issues since then, such as my Brother MFC-L2703DW not working even after downloading driver installation tool from Brother for MFC-L2703DW. Brother finally called me up and asked me to install Teamviewer, which I attempted to do for debian 64 bit, but kept getting "file not supported" message", same thing for 32 bit. My desktop is 64 bit. Brother support suggested I reinstall Ubuntu 19.10 latest vesion, but again the usb stick I have (32 GB) gives me message "no permissions" when I try to download from ubuntu to the usb. Brother then said I should reinstall Ubuntu this time from web and try using usb.   I downloaded .iso from Ubuntu website onto my hard drive. Then I used Ubuntu's own Startup disc creator software to flash my usb stick. However after I changed the bios boot sequence to usb first then rebooted, the first screen showing "ubuntu" or "advanced options" etc appeared but would not let me change the highlighted portion or would not start the flash. It was completely frozen. I tried rebooted and did the whole process again and again - no luck.   I tried again on a different machine using Linux Mint - same thing - the startup disc creator software just freezes up.   ANy ideas?


I am not sure what type of virus I have on my computer, and I am not sure if this is the right site to ask this type of question on, but here it goes:  About a month ago I downloaded something i believe to be the source of my issue and most likely contained a trojan horse. i noticed some unusual activity from this program called peerblock - an IP detecting and blocking program that i use frequently. Unusual IP sources ranged from "Ministry of Defense" to "Botnet Russia" to "Limelight Co.". These attempted connections were all blocked from peerblock, but i still found it weird so i unplugged Ethernet and left it alone for a couple days.  After about a week, i turned my computer on and was greeted with this same spamming of attempted IP connections from these "botnets". I noticed my PC was much slower and and i began to get ad malware without even downloading anything.  A few days later, I noticed my laptop getting these same IP connections from Peerblock. These issues still occur and havent been fixed. i also noticed my phone acting strange too. I reset my HTC M8 to factory settings due to its constant shutting off, failed incoming/outgoing texts, and battery loss. This reset fixed the problem, so i decided to reset my PC, as i believed the botnet may have spread to my phone somehow and could be removed the same way i did on my phone.  So now here i am, 2 restores later, and my PC is still detecting IP connections from odd sources such as "Pakistan Education and Research Network" and "Telephia", companies i have never heard of. Also, my PC is shutting off at random times during use, which didnt happen before i reset.  However, i was required to reset to win 8.1 Enterprise evaluation edition as win8.1 pro cant be restored to factory settings. Could this be a reason to the random shut offs?  Sorry for the long question, but i really would appreciate an answer :) Thanks!


Show that exponential map between complex matrix and general linear group is surjective

$\textbf{Problem}$ Trying to that $\exp: M_n(\mathbb{C}) \rightarrow GL(n,\mathbb{C})$  is surjective. $\textbf{Attempt}$ I started by considering a complex matrix A $\in M_n \mathbb{C}$, to this matrix I applied the Jordan normal form so $ A = \lambda I + N $ where $I$ is the identity matrix and $N$ is an upper triangular matrix. Thus, using the exponential map I get: $$ M_n \mathbb{C} \rightarrow GL(n \mathbb{C}) \\ A = (\lambda I + N) \mapsto exp(\lambda I + N) $$ Expanding the exponential we get and using the following Jordan Formula: $\textbf{Jordan Formula:}$ $$\mathbf J=\begin{pmatrix}\lambda&1&&\\&\lambda&\ddots&\\&&\ddots&1\\&&&\lambda\end{pmatrix}$$ $$f(\mathbf A)=\begin{pmatrix}f(\lambda)&f^\prime(\lambda)&\cdots&\frac{f^{(n-1)}(\lambda)}{(n-1)!}\\&f(\lambda)&\ddots&\vdots\\&&\ddots&f^\prime(\lambda)\\&&&f(\lambda)\end{pmatrix}$$ $$exp(\mathbf A)=\begin{pmatrix}exp(\lambda)&exp(\lambda)&\cdots&\frac{exp(\lambda)}{(n-1)!}\\&exp(\lambda)&\ddots&\vdots\\&&\ddots&exp(\lambda)\\&&&exp(\lambda)\end{pmatrix}$$ and I can identify this last matrix as an element of $GL(N, \mathbb C)$? If yes, is this enough to prove the surjectiveness of the map? What am I missing? Thanks in advance! Edit: I used @BenGrossmann and @user1551 hint, so I defined: $ M = log(\lambda I ) + N $ and $J = \lambda I + N $ then $\exp(M) = \exp(\log ( \lambda I) + N) = \lambda I \exp(N) $ as N is nilpotent of degree 3 thus $exp(N) \approx I + N + \frac{1}{2} N^2$, I plug this in the above equation and I get: $$ \exp(M) = \lambda I (\approx I + N + \frac{1}{2} N^2) $$ How can I prove that $\exp(M) = J$ from this?


Prove by induction that the number of derangements of length $n$ is $D_n = (n-1)(D_{n-1}+D_{n-2}), n>2$

Prove by induction that   $$ D_n = (n-1)(D_{n-1}+D_{n-2}), n>2 $$  where $D_n$ is the number of derangements of $n$ objects.  I am a little rusty in induction, and here's what I have done so far.  Basis step:  This is easy to prove and trivial, it works for $n=3$ and this is the basis step.  Induction step: Suppose the formula holds for $n$. I will use the relation:  \begin{equation} D_n = nD_{n-1} + (-1)^n, n\ge2 \label{u28.eq.1} \tag{i} \end{equation}  which I know is true because I have proved it before. So  $$ D_{n+1} = (n+1)D_n + (-1)^{n+1} =(n+1)D_n-(-1)^n $$  I use again formula \eqref{u28.eq.1} for $(-1)^n$ and obtain  $$ (n+1)D_n-D_n+nD_{n-1} = n(D_n+D_{n-1}), $$  which is of course what I wanted to prove. The thing is that I didn't use the induction step and I think I am wrong at some step, but I cannot tell where.


Is it immoral to read scientific articles if you find them as pdf on Google without having access to some official libraries?

I like to learn things even outside my university degree and I wonder if it is moral to read articles found online on blogs and other sources?


Even though a question may be closed by receiving 5 close votes, the votes do not necessarily need to agree.  I think this is a good behavior, but  (which it was) and found the question was closed as "not a real question".  This is unfortunate, while I'm happy to display my username and acknowledge that I voted to close, I'd like some additional transparency.  That is, if it was a 4-1 vote for "not a real question" vs "exact duplicate" I'd be interested in seeing that level of information.  The point is to be transparent about why the question was closed, and though 5 users may agree the question needs to be closed they may not agree why.  It's important to recognize all the reasons for closure, not just the majority reason.  I'd suggest displaying this information as something like:     closed on Jun 21 at 4:26 as:         not a real question by foo, bar, baz   exact duplicate by alice, bob      Once a question has been closed I'd argue it's more important to understand the rationale than it is to worry about an extra 2 lines of text. If the votes are 2,1,1,1 perhaps keep just 2 bullets, the first showing the majority vote, the second saying "for other reasons" as a summary of the change.  The point is to aggregate the summary by reason.


Is it possible to customize the colors of TexStudio itself (menus, toolbars, etc)?

So, to make it abundantly clear what I am asking for, here is an example picture edited (poorly) in a drawing software:     At left, you can see my current TexStudio look: the are where real text is indeed entered had its colors properly customized with a .txsprofile object. However, the menu toolbar, the tabs area and so on are still colored in light-gray, while I would like them to have a darker look (as in the image to the right).  Is it possible to achieve that somehow?  I am aware that plenty of questions have been asked here and elsewhere on the topic of TexStudio's colors. For example:         However, none of them really addressed the main point at hand: how to customize the colors of TexStudio's menus, toolbars, etc (not the colors of the text-editor part of TexStudio). The colors of the text-editor of TexStudio can be modified directly at the Syntax Highlighting options in the Tools>Configurations menu. However, rarely something is said about the other parts of TexStudio.  When a question pops up about this, it gets either no answers or very low-detailed reactions. For instance:       I realize that what TexStudio is doing is probably just retrieving the operational system color for it's menus, tool-bars and such. My question is whether there is anyway to bypass that and customize such colors.


What powers do US authorities have to search electronic devices at the border?

I'm referring here to situations in which people are seeking to enter or re-enter the US. Here I mean border to include airports. I'm interested not just in what powers the authorities technically have but how these powers are generally applied. Related question about the UK .  By search I mean access the contents of the devices by requiring the owners to turn them on and log in to facebook (etc) accounts.  Presumably also the answer would be different for US citizens vs non-US citizens. I assume that non-US citizens are free to decline access to electronic devices (including social media accounts), but in return border authorities are free to decline entry. In practice how commonly do such situations occur? Is it very rare for tourists to be asked to provide access to electronic devices? What has happened when they refuse to do so?  With regard to US citizens, what happens if they just flat out refuse to unlock any device or to comply in any way?  What about green card holders and any US non-citizens with some residency rights?


Given the sequence $\{x_n\}=(1+1/n)^n$, by using Bernoulli's inequality, $(1+a)^n>1+{na}$, and a little creative, clever algebra, it is a straightforward proof to show that $x_{n+1}/x_n>1$ and hence $\{x_n\}$ is a monotone increasing sequence. I thought that the same approach (the ratio of consecutive elements) and the same basic set of algebraic constructions might be used to show that $\{x_n\}=(1+x/n)^n$ for $x>0$ is also a monotone increasing sequence but it's escaping me, I'm afraid. I've seen other solutions that refer to the arithmetic-geometric mean inequality but I'd like to attempt a more basic solution that doesn't refer to that. Any hints to push me in the right direction?


travel from Dublin airport to Direct Ferries Terminal

Will arrive in Dublin Airport at 10:20AM and need to find our way to the Direct Ferries Terminal. Our ferry leaves at 2:30PM and should arrive an hour before departure. What would be the best mode of transportation? Cheapest?


Determining power and resistor values for a zener voltage regulator

Above is a zener diode circuit used for voltage regulation.  In Art or Electronics textbook theres a following exercise about choosing the right zener:    Always Vz = Vout and 10mA is the zener current wanted;   so R = (Vin(max) - Vz) / 10mA = (25 - 10) / 10mA = 1.5k Ohm.  and for Pz = ( Vin(max) - Vout) / R - Iout(min) ) * Vz  Pz = ( (25 - 10) / 1.5k - 0mA ) * 10 = 100mW  But actually if we can use Pz = Vz * Iz   Pz = 10V * 10mA = 100mW  I found different answers to this question in different forums. Am I doing something wrong here?


Different Google Searches return different titles for the same page

This is a hypothetical example of an actual problem. I hope it's clear.  When I search Google for dogs I can see my website homepage http://dogs123.com.au with the title "Dogs a mans best friend!".  If I search for dogs australia I see my website homepage http://dogs123.com.au with an old page title "Dogs blah blah". Clicking through on this result gives the up to date, current page with the proper title.  i.e. for two different searches, returning the same result, one returns the correct page title, and one returns an old page title.  Why is this happening? Is it something on my side or Google's?


I am looking for the probability of an outcome (x in Win, y in Opponent Actions and z in Opponent Cards) in a poker scenario.  I need a mathematical proof to simplify  $\Pr (x \mid y, z)$ to $\Pr (x \mid z)$


How to proceed if a professor does not answer the request for letter of recommendation?

I have written an email to a professor asking him for a letter of recommendation. It's been almost a week and he didn't answer back.  I have already seen questions on this topic here, saying that when a professor doesn't answer is probably because he forgot or he overlooked it. However my question is: what is the best thing to do next? Send him another email? Or try and see him in person?


Let $I\subset \mathbb{R}$ be open interval ,let $f:I\to \mathbb{R}$ be differentiable on $I,$ suppose $f''(a)$ exist at $a \in I$.  show that $$f''(a)=\lim _{h\to 0}\frac{f(a+h)+f(a-h)-2f(a)}{h^2}$$  how can we approach this .i was thinking of MVT.  applying MVT on $[a,a+h]$, we have $$f(a+h)-f(a)=hf'(\alpha_1)$$, where $\alpha_1\in(a,a+h)$  similarly $$f(a)-f(a-h)=hf'(\alpha_2)$$ where $\alpha_2\in(a-h,a)$  subtracting these we get  $$\frac{f(a+h)+f(a-h)-2f(a)}{h^2}=\frac{(f'(\alpha_1)-f'(\alpha_2))}{h}$$  now taking limit $h \to0$ both side, can we somehow  connect right hand side to $f''(a)$   any hint?? or some other method .i have seen this question already on stackexchange ,but most of them are using taylor expension up to 2nd order, but we are given  function is  twice differentiable at $x=a$,we donot know about twice differentiability at other points,so how can we use taylor expansion in this case???


Calculating Feature Overlap Area within Single Shapefile

I have looked throughout this site to find a method to calculate the overlap area of multiple polygons within a single shapefile but haven't found one that works for my case. I've tried the intersect tool but that doesn't seem to accomplish my task as it requires multiple input shapefiles.     Above I have included a image of my shapefile and the polygons. Each polygon represents an animal's territory and has several attributes assigned to it (age, sex, etc). In this example, there are some polygons (animal territories) that don't overlap and others that overlap multiple polygons. What I would like to do is to calculate the total overlap area (dark purple) within the shapefile. Eventually I would like to know the identities of all the animals that overlap each other. In the entire shapefile I have 300+ territories and multiple years of data so I need an approach that would be somewhat efficient.


"Install Spotify" can't be opened because Apple cannot check it for malicious software

I'm running macOS 10.15 Catalina Beta.  When I try to install Spotify I see the following error:    Is this a Spotify issue or a Catalina issue?  Thanks.


Can ultracentrifugation (very high gravity) influence time? (continued)

I was questioning myself this month how to prove/disprove the general, specific, special Relativity law concerning the relation between gravity and time distortion.  Then I saw on the web this question above coming up a couple years ago on this site but could not answer it anymore (discussion was closed with no clear answer). I think that using the new ultracentrifuges (2 millions Gs), it can be done.  Putting a solution of Iodine 135 isotope in the centrifuge (half life 6,59 hours) and a reference Iodine 135 sample for the same origin outside the centrifuge and spinning it for one week, there should be a very significant difference. As you can see I am not a Physicist and not following all your discussions, I am a genome scientist working a lot in early years with ultracentrifugation for DNA isolation and now retired and interested in the relation between time and gravity.  The question here is a simple experiment where the decay of Iodine 135 that has been spun for one week at 2 millions Gs is compared to the decay of a reference sample that has been left on the table.  My intuition is that there will be a difference between the two samples.  It is a simple experiment (may not be at 2 millions Gs) with a simple measurement.  Any one interested in doing it?    The possibility of slowing time artificially will have many applications.


Can I use a ethernet splitter to connect a router to two devices?

I have a portable mini wireless router with different functions (AP/Client/Router).  Can I use a ethernet splitter to give internet access to two devices? The router only has a ethernet port and connects to a wireless network (Cliente mode).  I know that a switch would be the best option but I dont have one and they are expensive.


Question: Disprove that for all integers $a,b$ that if $d=gcd(a,b)$ then $d=gcd(a^2,b)$ or $d=gcd(a,b^2)$ Attempts. I thought to first try $a=b$, then $d=a$ and $gcd(a^2,b)=b=d$ Ok, how about $a=0, b \neq 0$, then $d=b$ and $gcd(a^2,b)=b=d$ Ok, if $a,b$ are co-prime, then the $d=1$ and $gcd(a^2,b)=1$ Ok, maybe $a=b^2$, then $d=b$ and $gcd(a^2,b)=b$ Not sure what else to try. Maybe the problem is wrong? I copied it down carefully. Hints appreciated.


First difference in logs transformation produces biased results on back-transformation

I have a strongly trended series where the trend appears to be exponential and I believe the errors tend to be proportional to the current value. In order to convert it to a stationary series for purposes of forecasting, I expected to do the usual difference in logs transformation. However, it seems that changes have to be really tiny, or else you get a consistent bias strictly from the numerical approximation when it is transformed back into levels. For example, if you have a three percent change from a base of, say, 100, log(103) - log(100) = 0.0295588  (approximately. All calculations done with R.) So 0.029558 would be my dependent variable in this case. To reconstruct the value of the change, take the base, 100, times one plus the estimated change, and subtract the base from the result. 100 * (1 + 0.0295588) = 102.9559 (3 – 2.9559)/3 = 0.0147  Which is to say, a consistent underestimation by about one and a half percent, less for smaller changes, more for bigger ones. Changes in my data are usually smaller than 3 percent, but are that high or higher in about one observation in 210. To me, this seems like a big enough bias to worry about, especially since it is largest when we forecast big changes. Is there a standard correction for this? Or a different way of doing the back-transformation that gives results that are more numerically accurate?


I have a number of raster files saved locally which I use for basemapping in QGIS. I have built virtual raster fields to load these in one go but I'm looking to store them within my PostgreSQL database to share with other users.  Does anyone know whether this is possible?


How does anti-aliasing work, in general, for raytracing?

I am working on a raytracing Java program for fun. Here's one rendering:   As you can see I still have to implement anti-aliasing (and there are huge geometry problems I won't get in to). How would one go about this in a raytracing program, where the renderer doesn't really render lines, but individual pixels? Is it even possible? For example, in a scanline rendering, you could apply anti-aliasing after filling a triangle. But in a raytraced rendering, the program works pixel-by-pixel, and doesn't know where object's edges are, or where to smooth things out.  Thanks


Indian customs rules on bringing packed iPhone

I am a US citizen, who is a Person's of Indian Origin (PIO) card holder. I am planning to buy an iPhone 6s (60 rupees) as a gift for my mother (who lives in India). I would like to bring it to her in an unopened box.  Will I have a problem at Indian Customs for bringing in an unopened, brand new iPhone, along with my old iPhone which I am using?


Platformer collision detection problem - player snapping onto sides

I am having problems with collision detection. I am trying to make a simple platformer but when the player is falling or moving too fast it sometimes detects the wrong collision side. I am getting the side of the collision by checking the distance between the player and the sides of a block that are exposed to the player. I also tried detecting collision one axis at a time but this glitch still occurs.    blockCollision: function(block) {         if(this.x + this.width > block.x && this.x < block.x + block.width && this.y + this.height > block.y && this.y < block.y + block.height) {             let distanceLeft = Math.abs(this.x + this.width - block.x)             let distanceRight = Math.abs(this.x - (block.x + block.width))             let distanceTop = Math.abs(this.y + this.height - block.y)             let distanceBottom = Math.abs(this.y - (block.y + block.height))              if(distanceLeft < distanceTop && distanceLeft < distanceBottom && !block.collisionSides.includes('L')){                 this.velX = 0                 this.x = block.x - this.width             }             if(distanceRight < distanceTop && distanceRight < distanceBottom && !block.collisionSides.includes('R')){                 this.velX = 0                 this.x = block.x + block.width             }             if(distanceTop < distanceLeft && distanceTop < distanceRight && !block.collisionSides.includes('T')){                 this.jumping = false                 this.velY = 0                 this.y = block.y - this.height              }             if(distanceBottom < distanceLeft && distanceBottom < distanceRight && !block.collisionSides.includes('B')){                 this.velY = 0                 this.y = block.y + block.height             }              if(distanceLeft == distanceTop && !block.collisionSides.includes('LT')){                 this.x = block.x - this.width                 this.y = block.y - this.height             }             if(distanceLeft == distanceBottom && !block.collisionSides.includes('LB')){                 this.x = block.x - this.width                  this.y = block.y + block.height             }             if(distanceRight == distanceTop && !block.collisionSides.includes('RT')){                 this.x = block.x + block.width                 this.y = block.y - this.height             }             if(distanceRight == distanceBottom && !block.collisionSides.includes('RB')){                 this.x = block.x + block.width                  this.y = block.y + block.height             }         }     }


What is the difference between these Debian ISOs?

On , there are three different ISO images listed:  debian-7.7.0-i386-DVD-1.iso        2014-10-18 14:23  3.7G   debian-7.7.0-i386-DVD-2.iso        2014-10-18 14:23  4.4G   debian-7.7.0-i386-DVD-3.iso        2014-10-18 14:23  4.3G     What is the difference between these different ISOs?


Can I get US sales taxes refunded for electronics purchased while on vacation?

I'm visiting the US for vacations (specifically Manhattan) and wanted to buy a digital camera.  The guy at the shop told me that I can get back what I pay in NYC taxes for that camera if I present the ticket at the airport, when I'll be returning home. And that this is not applicable to clothes but it does to electronic stuff.   Is any of this true?


Where can I download the chrome i386 deb file?

Where can I download the Chrome i386 deb file? Google does not allow installing Chrome 32 bit from its web anymore. I am running xubuntu 15.10


Background I'm reading A Midsummer Night's Dream, and a lot of the dialogues and monologues are rhymes. But some times, these rhymes aren't rhymes at all. For instance  So should the murder'd look, and so should I, Pierced through the heart with your stern cruelty  A bit of a stretch to say the least. There are also cases where the written words end similarly, but spoken, they do not.  About the wood go swifter than the wind, And Helena of Athens look thou find  Question Did these word pairs ever rhyme? Was the state of the language ever such that these lines would be spoken on stage and rhyme perfectly? With "I" and "cruelty", one could pronounce the latter "cruel-tie", and I wouldn't scoff at the idea that this may have been common at some point. EDIT The I/cruelty rhyme is perfectly explained in another Q&A:  The same question still remains for the wind/find rhyme.


If $P(A \mid E) > P(B \mid E)$ and $P(A \mid  \neg  E) > P(B \mid \neg E)$, then is $P(A) > P(B)$ true? If it is, how to prove it?  Intuitively, I'm thinking it should be true, but I don't know how to prove it.


How to prove that $\sqrt 3$ is an irrational number?

Possible Duplicate:          I know how to prove $\sqrt 2$ is an irrational number. Who can tell me that why $\sqrt 3$ is a an irrational number?


Why in the name "Two sum problem" there is "sum" and not "sums"?


What is the condition for example $(number^c)^b=number^{cb}$ to be true?

What is the condition for $(\text{number}^c)^b=\text{number}^{cb}$ to be true?  I can't find it on google.ze so I asked it here on math.stackexchange.com.


What does it effectively mean when the same unit is specified in Wants and Before?

Let's say a unit (Unit1) has the following unit file configuration:  [Unit] Wants=Unit2 Before=Unit2   I read Wants as "Unit1, when started, will try to run Unit2 (but it's ok if it fails)".  I read Before as "Unit1 should be started before Unit2".  If the Wants makes Unit2 (try to) start before Unit1, but the Before makes Unit1 start before Unit2, what exactly is the reality? What happens here?  Thanks in advance!