I am a regular user of Firefox and Thunderbird. I have been using solely Ubuntu for more than a year. An interesting thing I noticed is that while Firefox is updated as quickly as possible (with a lag of at most several days) in Ubuntu repositories, the same is not true for Thunderbird.  The latest official version for Firefox is 74.0; it was released just two days ago and Ubuntu just updated it today.  The latest official version for Thunderbird is 68.5.0 which was released more than a month ago; while Ubuntu repositories still have not updated Thunderbird since version 68.4.1, which was released more than two months ago:    Version 68.4.1, first offered to channel users on January 9, 2020 Version 68.4.2, first offered to channel users on January 24, 2020 Version 68.5.0, first offered to channel users on February 11, 2020  Note: I am only interested about the supported PPAs and I am not currently using the "snap store" for these software. However, checking the snap store will reveal that the same (68.4.1) Thunderbird version is provided there too.

Why are packages in the official Ubuntu repositories older than the latest (upstream) versions from Debian Sid, PPAs, the authors, etc.?


My 20mo grabs at her genitals whenever she's naked (which is often as it's warm outside and she's toilet learning). She yanks on the outer labia and pokes at the inside. It looks rough to me, though she doesn't seem to care. I keep her nails trimmed so she doesn't scratch herself. I'm hesitant to stop her because I don't want her to feel shame for being curious about and exploring her body.   What's an appropriate reaction to this? I want to teach her it's ok to touch her own body, but she should be gentle so she doesn't hurt herself (Is she cognitively able to understand that if it hurts she has to stop? Can she make this connection?)and there are appropriate times and places to do this. What language should I use?

This has been going on a little while and the health visitor says its normal but we are a bit concerned about the force our child is using when he pulls at his penis: He really yanks it and it looks like it could do some damage...  Particularly when he stretches both as far as he can!  And the other day his nail cut him on his scrotum while I was changing him so I was even more concerned about bacteria.  How can I encourage him to stop doing it so forcefully without teaching him it's wrong to explore his body?


I think the bounty's reason and the addition information by the bounty offerer is missing in the info box.    Is this a bug? Or is it intentional?

When I click the bounty info icon on the iOS app. The added bounty description and reason is not shown.  For example:


Today I asked a question about which  install package was best for an -based PHP web-development environment. This seems straight-forward enough, and I believed it to be well within the defined scope of Stack Overflow from the FAQ:     "If your question (generally) covers   software tools commonly used by   programmers then you’re in the right   place to ask your question!"   Although the question got four upvotes in five minutes, it also collected one close vote. When I asked why, a user commented that, "by using the verb install multiple times you have disqualified the question for being about the programming tool itself".  This baffled me considering the number of accepted questions on Stack Overflow about installing programming related tools:         Immediately after that user's comment, however, the question was then (unhelpfully) migrated to Super User, a place totally unsuited to questions about preferable programming environments. It lasted a few minutes there before Super User moderators saw it was out of place on and moved it to Server Fault.  A place specifically for server administration.  And there it sits:   Is it really outside of Stack Overflow's scope to ask a question about which version of a programming language is best suited for using in a development environment? I'm not setting up or administering a web server as professional system administrator, just as a programmer.

There seems to be more than a few computer science/programming Stack Exchange networks (is that the correct term?). Stack Overflow, being the first, has by far the most users, questions, and answers.  What is the reasoning for creating the others, and are there clear guidelines for which kinds of questions should be posted? I can see a large amount of potential overflow, many cases of people not getting a good answer to their question, because the person who has the answer isn't browsing that particular network at the moment.  I understand that they were probably created for organizational purposes, but wouldn't it almost make more sense to just have them as categories under Stack Overflow, keep them separated but still connected, instead of making people have to create multiple 'account's, one for each network?  I am sure there was a very good reason to break them up, but as someone that is new to SE, it can be somewhat intimidating to decide which one to post in to ensure you get a good answer. For example, if I am a computer science student, my first instinct might to be to post in the computer science network, until I see that it literally has 1% of the users as the Stack Overflow network, which still seems to be for programming/computer science related questions.  So my second instinct would then to be to post it into the Stack Overflow site on the basis that I have a significantly higher chance of my question being seen and getting a good answer. Then I notice that there is also a 'programmers' network, and I don't even begin to know where that fits in. I, and I am assuming most people, will probably just post on Stack Overflow to be safe.  My question is, other than the short little description blurb of each one, is there a clear cut set of guidelines which what each network is intended for, what kinds of questions should go to each one, and is anything being done to encourage people to post in these newer, smaller (more specialized?) networks as opposed to just posting in big daddy Stack Overflow?  Now again, this is for computer science/programming/"why isn't this code doing what I want?" related questions, I am not saying that if I had a question about Linux or WordPress or something I would have the same confusion.


I use neural network to do classification. But instead of outputing one label, I want to ouput four independent labels such as [-1,1,1,-1]. Each of them is either 1 or -1, indicating a classification for a specific part of my input(image). However, I have about 3/4 -1s and 1/4 1s in my dataset, so the network tends to predict -1 everywhere, I use a simple mean square error loss now. What can I do to avoid such situation? THX!

I'm aware that there are many ways of dealing with datasets where there is a strong class imbalance in the target variable: downsampling the more prevalent and less important class, over-weighting the valuable minority class, etc. Are there any loss functions that are ideally suited for these types of problems? I've heard of AUC, but AUC sounds like a means of evaluating a model once its training is complete (correct me if I'm wrong). Log loss and squared loss penalize a model's over confidence, but overconfidence and class imbalance seem unrelated. Is that true?


I'm trying to increase disk space available on /dev/mapper/centos-root, however, I'm not sure why df -h is not reporting increased size.  $ sudo fdisk -l  Disk /dev/sda: 68.7 GB, 68719476736 bytes, 134217728 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x000a12e4     Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048     1026047      512000   83  Linux /dev/sda2         1026048   132120575    65547264   8e  Linux LVM  Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes   Disk /dev/mapper/centos-root: 64.6 GB, 64634224640 bytes, 126238720 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes   versus:   $ df -h Filesystem               Size  Used Avail Use% Mounted on /dev/mapper/centos-root   18G   13G  4.8G  73% / devtmpfs                 906M     0  906M   0% /dev tmpfs                    914M     0  914M   0% /dev/shm tmpfs                    914M  8.6M  906M   1% /run tmpfs                    914M     0  914M   0% /sys/fs/cgroup /dev/sda1                497M  140M  357M  29% /boot .host:/                  465G  432G   34G  93% /mnt/hgfs .host:/-vagrant          465G  432G   34G  93% /vagrant .host:/-etc-bolt         465G  432G   34G  93% /etc/bolt   In the fdisk command there is: Disk /dev/mapper/centos-root: 64.6 GB, 64634224640 bytes, 126238720 sectors  In the df -h command there is: /dev/mapper/centos-root   18G   13G  4.8G  73% /

I'm new to LVM and have been very confused by this:  I am transfering a large file to a partition that I thought had about 1.5 terabytes of space on it.  Near the end of the transfer, rsync exits with an error claiming that the partition is full.  I investigate and find the following:  $ sudo lvm lvs   LV        VG     Attr   LSize   Origin Snap%  Move Log Copy%  Convert   home      system -wi-ao  97.66G                                         log       system -wi-ao  48.81G                                         log.audit system -wi-ao   9.75G                                         root      system -wi-ao 341.59G                                         swap      system -wi-ao   4.88G                                         temp      system -wi-ao  97.66G                                         var       system -wi-ao   1.46T     This seems to imply that /var (the partition that I'm transfering to, has the amount of storage I expect.  However, then I see:  $ sudo df -h Filesystem            Size  Used Avail Use% Mounted on /dev/mapper/system-root                       331G  1.3G  313G   1% / /dev/mapper/system-temp                        95G  188M   90G   1% /tmp /dev/mapper/system-var                        95G   90G     0 100% /var /dev/mapper/system-home                        95G  188M   90G   1% /home /dev/mapper/system-log                        48G  264M   45G   1% /var/log /dev/mapper/system-log.audit                       9.5G  340M  8.7G   4% /var/log/audit /dev/sda1              99M   25M   70M  26% /boot tmpfs                 8.0G     0  8.0G   0% /dev/shm   I'm guessing this has something to do with the volume being resized at some point.  While I have reliable backups, I'd rather not interrupt services for the time it will take to get the backup and restore.  Thus, is there anyway to make the filesystem seen by the OS match the space available according to lvm without losing data?


I have a basic setup for my data like this:  myObj = {}; myObj[3] = {}; myObj[3].stuff = 'hello'; myObj[4] = {}; myObj[4].stuff = 'hello';   Now at some point i want to remove [4] from myObj. Currently i set it to false but this still exists in myObj. Like this Object {4: false}.  The issue here is if i want to loop myObj it will still loop the 4 which i don't want it to do.  How can I setup my data correctly so I can remove a given object and thus won't be iterated in a for loop.  Example of my loop is:  var i = 0; for(var j in myObj){   i++; } console.log(i); // = 2   Is there no way to rid of [4] so the total is then only 1?

How do I remove the key 'bar' from an array foo so that 'bar' won't show up in  for(key in foo){alert(key);}


Im making a simple model. I have added subsurface and mirror modifier. Im getting a divider or partition line between 2 mesh. I have on the clipping and merge in the panel. How can i dissolve the divider or partition line between. Any suggestion. Thanks (Please do not tag duplicate plz reply with comment or answer)

When I add a mirror modifier it sometimes doesn't mirror correctly, giving me an overlapping mesh. How can I fix this?


When someone says, "It's important to get it back on line as soon as possible," is on line one word or two?

I am still seeing uses of on-line, though I think it is incorrect. For example:     A web browser enables a user to go on-line/online.   Can you tell me which is the more appropriate to use, on-line or online?


Show that ${(n!)^2>n^n}$.  I am trying to use the ${AM \geq GM}$ inequality but I am not getting what I should get. Please help! Thank you!! :))

Show that if $n>2$, then $(n!)^2>n^n$.     My work: I tried to apply induction. So, at the induction step, I need to prove, $n^n>(n+1)^{n-1}$ Here, I tried to use induction again without any luck. I also took log of both sides, but I did not get anything. Please help!


I am German and was blacklisted December 2018 at the Chennai Airport without any explanation. I had founded a Trust in Germany to support children coming from very poor rural Areas in South India (35 children, Sponsors offering 10-15.-€/month/child).    As I found out later the mistake was sending the money directly to our Indian workers, instead of sending the money to an Indian Trust with FCRA number. I resigned from the Trust and our German Trust joined with an Indian Trust with FCRA number. I have contacted the Ministry of Home Affairs several times as well as the Bureau of Immigration New Delhi, the Indian Embassy in Berlin and the Indian Consulate in Frankfurt. So far no reply. Do you have any suggestion how to proceed further?   Would it be counterproductive to approach an Indian Lawyer? Or do you happen to know an Indian Lawyer specified in the matter?    I would be so grateful for any advice or help!!

I am a Bangladeshi citizen. Back in 2013, I went to India with a tourist visa and overstayed for four days. It was due to a gout attack in my feet but I don't have my medical papers to prove that.  I applied again in 2015 for a visa, at Dhaka, and they refused my visa and blacklisted my passport, writing some numbers and date on it. Now I am not able to get an Indian visa.  How I can remove my passport from the blacklist and get a new Indian visa? Do I need a Indian immigration lawyer to do this?


Let m and n be any two positive integers. Then prove that :  Φ(mn) = Φ{ (m, n)Φ[m, n] } where (m,n)=the g.c.d.of m and n and [m, n]= the l.c.m of m and n

If $m, n$ be positive integers, prove that $\phi(mn)=\phi((m,n))\phi([m,n])$, where $(m,n)=$ gcd of $m, n$ and $[m, n]=$ lcm of $m, n$.   I have no idea to solve this question. Please help me to solve the problem.


I have no clue really, I know that $x$ can be written as $\ln (e^x)$ and that's it.

As the natural $\log(x)$ function is the inverse of the exponential $e^x$ and $\log(x +1)$ is the inverse of $e^x - 1$, what it the inverse of $e^x + x$?


I don't want to see the shadow cast on the wall like the circled one with red pen the picture. How can I cancel such light effect?  I found an answer that said to go the "word" and "surface" to remove it. I am not sure that it's the same thing (link: )  but I did not see the "surface" option in my "world" column.  Thank you for helping me, I really appreciate it

Zooming in to inspect texture details in 3D view clips some closer faces like shown in the image. It's not the camera view so changing camera settings doesn't help.   Where can the distance to the clipping plane be adjusted?


For any $n>2$, among $2^n-1$ and $2^n+1$, at most one is prime.    I have no clue :(

I am trying to prove that not both integers $2^n-1,2^n+1$ can be prime for $n \not=2$. But I am not sure if my proof is correct or not:  Suppose both $2^n-1,2^n+1$ are prime, then $(2^n-1)(2^n+1)=4^n-1$ have 2 precisely two prim factors. Now $4^n-1=(4-1)(4^{n-1}+4^{n-2}+ \cdots +1)=3A$. So one of $2^n-1, 2^n+1$ must be 3. which implies $n=1$ or $n=2$ (rejected by assumption). Putting $n=1$, we have $2^n-1=1$ which is not a prime. Hence the result follows.  I also wanna know if there is alternative proof, thank you so much.


I am trying to create a circuit to drive a hand drill motor as seen in this drawing with just relays. The current formation to make it go forward, switching 2 and 3 at the same time to make it go backwards, and switching 1 to make it stop. I expect it to be ~18V at ~20A when running. Do I need flyback diodes for this to work correctly and if so how would I go making that calculation and selecting that part? When switching 2 and 3 at the same time is there anything I should be concerned about?

I've got a motor hooked up to +12V on one side and -12V on the other, being driven in both directions by a Motor controller (). We were getting voltage spikes in the common ground after sending big impulses to the motor, so we put a flyback diode from the negative cable to the positive cable. However, this caused the motor to be less responsive in the reverse direction. How do we correctly prevent voltage spikes in the ground from this type of motor?


I'm trying to do a comparison in Java with 2 strings containing a extended ASCII character.  boolean result = "éasdfasdf".substring(0,1).equals("é");   Can somebody explain why this results false? I think it has something to do with character encoding, but I can't figure out what exactly the problem is here...  Update: ideone.com does successfully run these 2 lines, so the problem is locally in my box. I think I found some more proof of that:  System.out.println("éb".charAt(1) == 'b');   Does also fails... Can it be the problem of 2 different character encodings?

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


I have what appears to be a simple question but I do not know if my method is correct.  I have to find what the subgroup of $S_5$ generated by $(123)$ and $(12345)$ is.  So I have worked out that the product of the above permutations is $(52134)$ so now do I compute the 5th power of the product I calculated? Then somehow find out what subgroup that is?

The Question I am trying to solve reads :  Find the order of a subgroup of $S_5$ generated by the elements $s=(123)$ and $r=(12345)$. Is this group sovable ? Is it nilpotent ?  I tried to compute a couple of terms but then I realized this subgroup is way large, and computing the elements one by one might not be a good idea (Is there another way to compute the order ?)  My calculation shows : $r, r^2, r^3, r^4, rs, r^3s, sr $ are all $5-$cycles but there are elements like $r^2s=(14)(25)$ and also $r^4s=(354)$...It seems that all sorts of things can happen in this subgroup...I do not even know how to approach the solvability and nilpotency before I know what the subgroup is...  I already appreciate your hints/ideas/answers


I am trying to classify rings of order 10. I believe the only possible ring is $\mathbb{Z_{10}}$. Thus I am trying to find a map from my ring $R$ to $\mathbb{Z_{10}}$. The most obvious map $f: R \rightarrow \mathbb{Z_{10}}$ such that $f(1)=1$ and $f(n)=[n]_{10}$. I was able to prove that it was a homomorphism and surjective. However, I am stuck at proving injectivity. Can anyone please give me some hints

How do I prove that a finite ring $R$ of order 10 is isomorphic to the ring $\mathbb{Z}/10 \mathbb{Z}$?    I know that as a group under addition, $(R,+)$ is isomorphic to the group $(\mathbb{Z}/10 \mathbb{Z}, + )$, but the multiplication is rather mysterious to me.


I'm facing an issue when we redeploy Salesforce. The connect applications on each environments lose all of their correct settings. I'm hoping to find a way around this. My main goal is to keep the connected apps the same, with static values as they are connected to the likes AWS, so losing these settings basically breaks our setup and we have to manually fix each app. I've investigated using the developer API to refresh each connected app with the correct settings after each deployment.But the issue with that is it seems I have to manually go onto Salesforce after the app is created through the automated process and save the app for it to become exposed/available for use. I'm also looking into using DX Packaging to keep the settings static for each connected app. I haven't had much luck getting this to work yet as I haven't much Salesforce experience and our deployment process was setup by someone else. Apologies if I'm missing something obvious, I'm new to Salesforce and still becoming familiar with terminology of the technology

I am attempting to create a web app (ruby on rails) that requires access to a user's Salesforce environment to perform some REST api calls (SOQL queries) and in doing so I've implemented the . On a dev org I have access to I have created a connected app and am able to successfully connect to that connected app, authorize against it with a user from that environment and then with the returned authorization code I'm able request an access token and make REST calls. However my goal is to allow a salesforce user to authorize access to their org without having a connected app installed in their environment? How is this done?  To look at this same issue from a different perspective, how does a website such as  or  allow a salesforce user to authorize access to their environment?


I will first let you know the problem, then I will tell you what I tried : I have to solve the congruence system, $20x \equiv{9} \mod{30}$ $9x \equiv{12} \mod{33}$ $36x \equiv{49} \mod{60}$ With the Chinese remainder theorem, I tried to replace the equations because $30$, $33$ and $60$ have commons factors. I found prime decomposition for all modulo $30$, $33$ and $60$ and replaced those prime factor as new modulars. By simplifying I found : $2x \equiv{0} \mod{4}$ $x \equiv{3} \mod{5}$ $9x \equiv{1} \mod{11}$ I found $x=1728$ for the new system but it does not match with the first system. Maybe there is no solution?

Isn't finding the inverse of $a$, that is, $a'$ in $aa'\equiv1\pmod{m}$ equivalent to solving the diophantine equation $aa'-mb=1$, where the unknowns are $a'$ and $b$? I have seem some answers on this site (where the extended Euclidean Algorithm is mentioned mainly) as well as looked up some books but there is no mention of this. Am I going wrong somewhere or is this a correct method of finding modular inverses? Also can't we find the Bézout's coefficients by solving the corresponding diophantine equation instead of using the extended Euclidean Algorithm?


I want to figure out why my array that is declared outside of a for loop refuses to be properly initialized by a for loop in order to be used by another for loop. Googling "array null pointer exception" and "null arrays" kept bringing me to errors about not initializing the array. Hopefully that's not what's happening here. (I don't think it is.)  public static void main(String[] args)     {         Student[] students = new Student[25];               for(Student student : students)         {             int grade=(int)(Math.random()*4 +1);             student = new Student("bob",grade);             System.out.println(student); //debug 1         }         for(Student student : students)         {             // if (student.getGPA() == 0){             //     System.out.println("No data entered for student.");             // }             System.out.println(student); //debug 2         }     }   This block is just main, and it's in another valid class named after the file. Student is a class that I excluded because it has nothing to do with the question being asked, but for reference it takes a String name and an int gradeLevel as parameters and has toString() and getGPA() methods (among others).  What I want from debug 2 and get from debug 1: something along the lines of  bob: Freshman; GPA: 0.00 bob: Senior; GPA: 0.00 bob: Freshman; GPA: 0.00 bob: Sophomore; GPA: 0.00 bob: Senior; GPA: 0.00   What I have from debug 2:  null null null null null   I want the print statement marked "debug 2" to print the same thing as what "debug 1" does, which is a column of the toString values of the students. Instead, I'm just getting a column of null for debug 2 but the correct output for debug 1.   The commented-out code was the source of null pointer exceptions because null objects do not have getGPA() methods. I have no idea why the array remains full of nulls, though. The fact that there aren't nulls from debug 1 tells me that the array is indeed being initialized, but that the values aren't staying in the array.  I probably completely misunderstand something or the use of something here.

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


I have an issue with Dynamic cast  with inheritance.   I have Shape which is a base class and Rectangle which is a deviated class.  In my Rectangle.h file, I have the following  class Rectangle: public Shape   In my main class, I create a vector of Shape class named record  std::vector<Shape> record;   In my Shape.h file, I have the virtual function computeArea().   virtual double computeArea();   My Rectangle.h file contains the function double computeArea()  I am trying to dynamic cast the Shape into Rectangle to compute the area  for(int i=0; i < record.size(); i++)     {         cout << record[i].getName() <<endl;         if(record[i].getName() == "Rectangle")         {             Rectangle& rectest = dynamic_cast<Rectangle&>(record[i]);             cout << rectest.computeArea() << endl;         }     }   However,I got this error "terminate called after throwing an instance of 'std::bad_cast' what():  std::bad_cast Aborted"  Any one know what could be the issue?  Thank you.

Someone mentioned it in the IRC as the slicing problem.


The maximum likelihood estimator is often compared to the least squares method. I'm struggling to see how these things are related at all. I would like to understand what the maximum likelihood estimator means in practice. Can you adapt the maximum likelihood estimator to the example below and use the example to explain it?  Let's say we are trying to predict house prices (target) from the size of the house (as the only feature). We are using Linear Regression, so we are trying to learn (optimize) parameters B0 and B1 in predicted price = B0 + B1 * size. If we are using Ordinary Least Squares, we want to minimize the sum of squared differences between prediction and real target. For example, if we predict target 1000 for some house and the actual target is 900, the difference is 100. The squared difference is 100^2 = 10000. So this house would increase the sum by 10000. We want to choose B0 and B1 in a way that minimizes the sum of these squares. Simple.  Now substitute Maximum Likelihood Estimator in place of Ordinary Least Squares. Wikipedia tells us that it's "finding the parameter values that maximize the likelihood of making the observations given the parameters". How does this relate to the example with parameters B0, B1 and a difference of 100 between predicted target and real target?

I am new to Machine Learning, and am trying to learn it on my own. Recently I was reading through  and had a basic question.   Slide 13 says that "Least Square Estimate is same as Maximum Likelihood Estimate under a Gaussian model". It seems like it is something simple, but I am unable to see this. Can someone please explain what is going on here? I am interested in seeing the Math.   I will later try to see the probabilistic viewpoint of Ridge and Lasso regression also, so if there are any suggestions that will help me, that will be much appreciated also.


I had Windows 10 installed along Ubuntu, and would choose from grub loader.  I later uninstalled Win 10 and installed Win 7 in its place, I updated grub in Ubuntu but the Windows 10 entry in grub did not go away.  I now have two entries, both entitled Windows 10, one in /dev/sda1 and the other in /dev/sda2.  Both load Windows 7, but not on the first try. When I initially load it, the screen is dark, while Windows has loaded in the background (I can hear the sounds).  I have to power-off the computer, then choose Windows again for the screen to work. Sometimes I have to repeat this more than once.  I don't know much in Linux so I can't tell if the problem is from Windows or grub.

I know this might be a duplicate, but I've read a lot of threads about this and none pointed me to the solution.  When loading GRUB2 I have a black screen (with static white cursor on the upper left) which goes away as soon as the Ubuntu login page comes up, but stays there forever if I boot Windows (even though I can hear the 'login sounds').  I have a dual boot system with Ubuntu 14.04 and Windows 7 (both 64-bit) and I have a NVIDIA VGA. The Windows installation used to work just fine, with the VGA doing its job. My monitor was plugged on the motherboard when I fresh installed 'trusty tahr' (I have a integrated intel graphics CPU) and after that I immediately installed the video card drivers from the official repo (nvidia-331 I believe). Their installation was successful (at least from what I see from the 'Nvidia X serve settings' tool). After that, if I plug the monitor on the video card, grub goes on the black screen, but I can anyway boot Ubuntu and when the login page comes up the video output is normal. The same cannot be told when Windows boot.  I tried many suggested fixes: nouveau.modeset=0, nvidia.modeset=0, nomodeset options in the /etc/default/grub file and I also tried blacklisting the corresponding kernel modules adding a .conf file in /etc/modprobe.d. None of that solved my problem.  I insist that this must be a grub video problem, since if I plug my monitor on the mother board I can boot successfully both Ubuntu and Windows and also the boot-repair tool for Ubuntu doesn't find anything significant (see ).  I'm currently out of ideas, has anyone any suggestion? It would be much appreciated!  Lorenzo


i'm using a shared hosting for my Drupal Website and I'm having some security troubles especially with folders and files permissions. So after some researches in the  and some  and even in  , I made my configuration like this:     Any Drupal php file: 444  Drupal folders: 555 SITES folder: 755 SITES/DEFAULT folder: 505 SITES/ALL folder: 705 SITES/ALL files:604 settings.php : 404 SITES/DEFAULT/FILES folder: 775   Is there anything to correct or to adjsut for more security?

I'm gearing up to deploy a Drupal 7 site and I can't find any documentation about what the recommended security-conscious file and directory permissions should be set to.  Specifically default/files/ (also sub directories?), settings.php, .htaccess and anything else I should be aware of.


I have the following code:  #include<stdio.h> int main(int argc, char const *argv[]) {     float min, max, step;     min = -0.85, max = 0.85, step = 0.002;     int rank = 3, total = 4;     float step1 = min + (max - min) * rank / total; // should be 0.425     printf("%f %.7g\n", step1, step1); // 0.425000 0.4250001     float step2 = min + (max - min) * (rank + 1) / total - step; //should be 0.848     printf("%f %.7g\n", step2, step2); // 0.848000 0.848     float noc = (step2 - step1 + step) / step; //should be 212,5     printf("%f %.7g\n", noc, noc); // 212.499985 212.5     int nol = 1200;     int result = (int)nol * noc; //should be 255000     printf("%d\n", result); // 254999     return 0; }   This is a fragment of code isolated from a project I have to do. The final result should be 255000, but for some causes, it shows 254999. Can someone please explain me what happens in the process? I have read somewhere that multiplying a floating number with 10^k and then dividing back solves such problems, but in this case, due to the variable step varying from 0.000001 to 0.1, I can't actually use that (in the same way, I can't use a defined EPSILON). What else can I do?   Thanks in advance!  P.S.: I have used double and long double as well, but with same problems, only this time error propagates from a further decimal. I am using gcc 4.8.2, under Ubuntu 14.04.1.

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


Is there an Ubuntu Core image for the Ubuntu Core on Raspberry Pi 3 B+?  When I use ubuntu-core-16-pi3.img.xz on my Raspberry Pi 3 B+, the red LED lights up solid, and I see the rainbow screen.  I have tested the image, and it works on my Raspberry Pi 3.  I've also tested NOOBS v2.9.2 "Raspberry Pi Desktop, Debian" on the Raspberry Pi 3 B+, so I'm confident that that device is at least functioning.

If it's available, I can't seem to find it on the site. If it's not, can someone please link me to as much information as possible so that I can track progress on developments? Thanks.


I am a new beginner in stats. I have specifically diverted my attention towards this because, I wish to understand the concept of Deep Bayesian Learning, so I am starting with the basics. The question is:   The Bayes rule equation is given by   $P(X | Y)$ = $\cfrac{P(Y | X). P(X)}{P(Y)}$  But, I have noticed in some places, the denominator being ignored entirely and using just the numerator of the RHS of the equation. making it:  $P(X | Y)$ = $P(Y|X).P(X)$  Is there some special case where we can ignore the P(Y)? as in when P(Y) = 1? But, if that's the case, wouldn't all the things become very easy: P(Y | X) will become 1, and P(X | Y) will be just P(X) and done.

Bayes theorem goes $$ P(\textrm{model}|\textrm{data}) = \frac{P(\textrm{model}) \times  P(\textrm{data}|\textrm{model})}{P(\textrm{data})} $$  This is all fine. But, I've read somewhere:     Basically, P(data) is nothing but a normalising constant, i.e., a constant that makes the posterior density integrate to one.   We know that $0 \leq P(\textrm{model}) \leq 1$ and $ 0 \leq P(\textrm{data}|\textrm{model}) \leq 1$.    Therefore, $P(\textrm{model}) \times P(\textrm{data}|\textrm{model})$ must be between 0 and 1 as well.  In such a case, why do we need a normalizing constant to make the posterior integrate to one?


Let $V : \mathbb{R}^n \rightarrow  \mathbb{R}$ be (strictly) convex and continuously differentiable on $\mathbb{R}^n$. Show that for any $y \in \mathbb{R}^n$ and any $x \in \mathbb{R}^n$ $$ V(y) \geq V(x) + \nabla V(x)^\top(y-x) $$ For $n=1$ this implies that for any $x \in \mathbb{R}$ and for any $y \in \mathbb{R}$, $V(y)$ lies above the tangent line to $V$ at $x$.

I noticed many identical questions on this site relating to equivalent definitions of convexity, see for example , , , , , ,  and there might be more. So I wanted to create a "big list" of equivalent definitions of convex functions, I will start with some equivalent definitions and post my proofs in my answer below. Feel free to add any other equivalent definitions. This question can then serve as an abstract duplicate. Claim. Let $n\in\mathbb N$ and $f\in\mathcal C^1(\mathbb R^n)$. Then the following are equivalent:  $f$ is convex, i.e. $f(\lambda x_1 + (1-\lambda x_2))\le\lambda f(x_1)+(1-\lambda)f(x_2)$ for all $\lambda\in[0,1]$ and $x_1,x_2\in\mathbb R^n$. For all $x,y\in\mathbb R^n$, $\langle\nabla f(x)-\nabla f(y),x-y\rangle\geq0$. For every $x,y\in\mathbb R^n$, $f(y)\geq f(x)+\langle y-x,\nabla f(x)\rangle$.


Found this technique to verify if the email address is in correct form of not.  function check_email($email) {           if( (preg_match('/(@.*@)|(\.\.)|(@\.)|(\.@)|(^\.)/', $email)) ||              (preg_match('/^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/',$email)) ) {               return true;         } else {              return false;         }            }   I Am a newbie in php. What this big regex commands mean?

I don't really understand regular expressions.  Can you explain them to me in an easy-to-follow manner?  If there are any online tools or books, could you also link to them?


static Task<int> GetPrimeCountAsync(int start, int stop) is for counting the number of primes in a closed interval [start,stop] where 2 < start <= stop. static void WrapperAsync() is for printing a list of 10 executions of GetPrimeCountAsync, each with a closed interval spanning from i == 0 ? 3 : 1000_000 * i to 1000_000 * (i + 1) - 1, where i spinning from 0 to 9. Inside this method, there are 3 cases, only one is activated.   when case 1 is activated, the result is as follows:   when case 2 is activated, the result is as follows:   when case 3 is activated, the result is as follows:      Questions  If we compare case 1, 2 and 3, there are the same glitches in case 1 and 2 but not in case 3. The case 3 is the wanted result.  Actually the glitches can be removed by buffering the loop counter with local variables as follows:  int start = i == 0 ? 3 : 1000_000 * i; int stop = 1000_000 * (i + 1) - 1;   And then just pass start and stop to GetPrimeCountAsync and WriteLine.  The question is: What causes these 2 glitches in case 1 and 2?  Complete Code  using System; using System.Linq; using System.Threading.Tasks; using static System.Console;   class Program {     static void Main()     {         WrapperAsync();         WriteLine("Ended...");     }       static void WrapperAsync()     {         for (int i = 0; i < 10; i++)         {             //int start = i == 0 ? 3 : 1000_000 * i;             //int stop = 1000_000 * (i + 1) - 1;              // case 1: OnCompleted             var awaiter = GetPrimeCountAsync(i == 0 ? 3 : 1000_000 * i, 1000_000 * (i + 1) - 1).GetAwaiter();             awaiter.OnCompleted(() => WriteLine($"The number of primes between {(i == 0 ? 3 : 1000_000 * i)} and {1000_000 * (i + 1) - 1} is {awaiter.GetResult()}"));              // case 2: ContinueWith             //var task = GetPrimeCountAsync(i == 0 ? 3 : 1000_000 * i, (i + 1) * 1000_000 - 1);             //task.ContinueWith(t => WriteLine($"The number of primes between {(i == 0 ? 3 : 1000_000 * i)} and {(i + 1) * 1000_000 - 1} is {t.GetAwaiter().GetResult()}"));              // case 3: without OnCompleted and without ContinueWith             //var task = GetPrimeCountAsync(i == 0 ? 3 : 1000_000 * i, (i + 1) * 1000_000 - 1);             //WriteLine($"The number of primes between {(i == 0 ? 3 : 1000_000 * i)} and {(i + 1) * 1000_000 - 1} is {task.GetAwaiter().GetResult()}");         }     }      //  Note that 2 < start <= stop      static Task<int> GetPrimeCountAsync(int start, int stop)     {         var count = ParallelEnumerable.Range(start, stop - start + 1)                     .Where(i => i % 2 > 0)                     .Count(j => Enumerable.Range(3, (int)Math.Sqrt(j) - 1).Where(k => k % 2 > 0).All(l => j % l > 0));          return Task.Run(() => count);     } }

I met an interesting issue about C#. I have code like below.  List<Func<int>> actions = new List<Func<int>>();  int variable = 0; while (variable < 5) {     actions.Add(() => variable * 2);     ++ variable; }  foreach (var act in actions) {     Console.WriteLine(act.Invoke()); }   I expect it to output 0, 2, 4, 6, 8. However, it actually outputs five 10s.  It seems that it is due to all actions referring to one captured variable. As a result, when they get invoked, they all have same output.  Is there a way to work round this limit to have each action instance have its own captured variable?


Without updating update_history how can I ensure my text file will contain:  hello\ world john\ doe   That is how can I pass $greeting $name to a function or command as hello\ world john\ doe.    function update_history {   history=/tmp/hist   grep -qF "$1" "$history" \     || (combinations=$(echo "$1" | cat - $history) \         && echo "$combinations" > $history) }  greeting=hello\ world name=john\ doe  update_history "$greeting $name"

Or, an introductory guide to robust filename handling and other string passing in shell scripts.  I wrote a shell script which works well most of the time. But it chokes on some inputs (e.g. on some file names).  I encountered a problem such as the following:   I have a file name containing a space hello world, and it was treated as two separate files hello and world. I have an input line with two consecutive spaces and they shrank to one in the input. Leading and trailing whitespace disappears from input lines. Sometimes, when the input contains one of the characters \[*?, they are replaced by some text which is is actually the name of files. There is an apostrophe ' (or a double quote ") in the input and things got weird after that point. There is a backslash in the input (or: I am using Cygwin and some of my file names have Windows-style \ separators).   What is going on and how do I fix it?


I'm getting the following errors Xorg log file(Ubuntu 20.04). I have tried to google it but I have not found a reasonable answer. What does this error mean? [  7355.001] (II) event9  - 2.4G Mouse: SYN_DROPPED event - some input events have been lost. [  7358.334] (II) event9  - 2.4G Mouse: SYN_DROPPED event - some input events have been lost. [  7359.634] (EE) client bug: timer event9 debounce: scheduled expiry is in the past (-87ms), your system is too slow [ 10596.655] (EE) client bug: timer event9 debounce: scheduled expiry is in the past (-17ms), your system is too slow

whenever I move my mouse enough it causes high cpu usage. Screenshot provided is on a fresh X session.    This also causes some frequent freeze ups if I'm running some other programs e.g gaming.  [1075299.085] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077813.434] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077814.079] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077814.246] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077814.682] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077831.975] (EE) client bug: timer event4 debounce: offset negative (-18ms) [1077831.975] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost. [1077831.975] (II) event4  - Corsair Corsair Vengeance M90 Mouse: WARNING: log rate limit exceeded (5 msgs per 30000ms). Discarding future messages. [1120008.128] (II) event4  - Corsair Corsair Vengeance M90 Mouse: SYN_DROPPED event - some input events have been lost.   Is there any way for the CPU usage not to be this high?  EDIT:  I tried with other mice. The CPU usage appears to increase with the Mouse DPI or to be exact, a generic mouse will cause a CPU usage spike, but not as much as a gaming mouse.  I also checked if I have hardware acceleration enabled.  $ glxinfo | grep "direct rendering" direct rendering: Yes   EDIT 2:  CPU is an AMD FX-6350  GPU is AMD RX Vega 56


I wanted to get some numbers on how fast is multiplication over addition. I wrote a simple code where I am multiplying 2 numbers, finding the time taken. Then I am adding the 2 numbers and find the time taken. The results are a bit disturbing. Before I show the results, here is the code  package com.np.fun;  import java.util.Scanner;  import org.apache.commons.lang3.time.StopWatch;  public class HowSlowIsMultiplication {  public static void main(String[] args) {     Scanner scanner = new Scanner(System.in);     int x = scanner.nextInt();     int y = scanner.nextInt();     long z;     StopWatch stopWatchMultipy = new StopWatch();     stopWatchMultipy.start();     z = x*y;     stopWatchMultipy.stop();     System.out.println("Time taken for multiplication is : " + stopWatchMultipy.getNanoTime());     StopWatch stopWatchAdd_1 = new StopWatch();     stopWatchAdd_1.start();     for(int i =0 ;i <Math.min(x, y); i++){         z = z + Math.max(x, y);     }     stopWatchAdd_1.stop();     System.out.println("Time taken for adding in less for loops is : " + stopWatchAdd_1.getNanoTime());     StopWatch stopWatchAdd_2 = new StopWatch();     stopWatchAdd_2.start();     for(int i =0 ;i <Math.max(x, y); i++){         z = z + Math.min(x, y);     }     stopWatchAdd_2.stop();     System.out.println("Time taken for adding in more for loops is : " + stopWatchAdd_1.getNanoTime()); }   }  I tried this with varying values of x & y. Here is the output for x=10000 and y=5000 (all times are in naoseconds) Time taken for multiplication is : 61593 Time taken for adding in less for loops is : 1622599 Time taken for adding in more for loops is : 1622599  As you can see, multiplication is several orders of magnitude faster than addition.  Any reasons for this?

How do you write (and run) a correct micro-benchmark in Java?  I'm looking for some code samples and comments illustrating various things to think about.  Example: Should the benchmark measure time/iteration or iterations/time, and why?  Related:


I've been searching and came across to a lot of very useful information already on the VWP and implications on staying longer than 90days under the VWP. I'm fully aware of the fact that you can stay for a maximum of 90days under the VWP, and I have read a lot about other experiences but I didn't came read any topics about my scenario which is as follows.  I'm currently staying under the VWP in the US and my return flight back home is scheduled on April 5th. As I am planning to stay another 3 months in the US I considered the following solution to stay for another while.  Potential scenario  If I would fly to Colombia by the end of March and come back to the US, lets say on April 2nd, before my scheduled home flight. My understanding is that in general, leaving the country to Colombia and coming back would count as a reentry, and if I get admitted in to the country under the VWP I would get another 90days. After the admission I will cancel or reschedule my flight home to a later date (within the new 90 days).  However, what I couldn't find is: - Do I get a new reentry, even though I reenter before my initial scheduled home flight? I would assume that my trip to Colombia counts as "leaving the country" for my first admission to the US? - If yes, can I change my initial flight afterwards without having any troubles?  - Does anyone has any experiences with this and would you recommend to change my home bound flight before or after the reentry?  Hoping to hear some experiences from people who did this before. As mentioned, I did read a lot about this and I am aware of the risks, but I'm rather hoping to hear some experiences, especially suggestions about if and when to change my home bound flight would be very helpful.  Thx all!

I am a British citizen visiting the USA in early August for a two week vacation with friends. After the holiday I'm returning to my home in the UK for three weeks. After that I will return to the USA and will be working for my British employer under the Visa Waiver Program for a period of 80-85 days.  I have read already that there is technically no problems with this under ESTA rules, but should I limit this working period to a shorter time frame (e.g. 70 or so days) so that it does not negatively affect the decision made by the POE officer? Ideally I would love to be over in the states for the near-full 85 day period.  Any advice or previous experiences anyone can offer?  Some clarifications: As confirmed by the immigration attorney, as I am employed by my UK employer, it will be regarded as a business trip, the important part being that I will be working officially as a consultant for my UK employer just overseas for the allotted 85 or so days


I would like to know if there is a rule when to pronounce ah in RP versus ae in GA. Is it a question of vocabulary or is there a rule for that?  Examples: dance- in RP is pronounced ah  but in GA  it is pronounced ae  or: can't, romance, cast, fast, etc.

How can I know, precisely, when to differentiate the sounds of the letter a, like in: apple and vault?


I've been baking a fluid simulation for the past four hours, and I decided to set up the materials in my scene while I was waiting.  While doing the materials, blender crashed.  Is there anyway that I can resume the baking right where it left off?  Thanks!  (This is seperate from ).

It happens sometimes that after finishing bake (e.g., for fluid simulation) we wish we could continue the simulation for two more seconds :(    How to use the cached bake to continue the simulation?  We played with the settings, but with no success.


Can I make my computer use both Ethernet and Wifi connections to download files from multiparts supported servers simultaneously or download torrents faster and use both connections to download different parts of torrent file simultaneously, thus increasing my total speed for specific multipart supported download operations.  Note: I have 2 Internet services at my home both have their own routers so I want to use both of their speed at the same time to boost my total connection speed can I do that, if so how?

I am technically knowledgeable enough to know that this most likely isn't possible, BUT, I am curious just the same (it must be put to rest). Is there anything preventing us from creating a means to use two different internet connections, like two different ethernet cards or an ethernet card and a wireless card, and using the two IP addresses at once for more internet speed?  My specific situation is that I would like to use both a wireless card and my wired connection on my machine running Kubuntu 13.10. Using two internet connections would allow me to do things like:   Torrent and browse simultaneously without lag Open Firefox with multiple tabs faster (?) Download a couple or a few large files at once double time Increase overall internet connection speed (?)


I have a drupal in  and is working perfect, but when I move drupal to my root folder and run  the homepage is work but internal paths is not working, is to say:   drupalsite.com.mx  =>is work! drupalsite.com.mx/user  =>is NOT work! drupalsite.com.mx/products  =>is NOT work! drupalsite.com.mx/service  => is NOT work!   All paths show error 404 and I cant into the user /admin page.... Help me please!

I installed Drupal 7 on Wamp Server. I can't find any checkbox or link to enable clean URLs; I see only the Run the Clean URL Test button.  How can I enable clean URLs?


I am pretty new to QGiS and to cartographic software in particular. I wanted to create some maps of some cities in the Arab Gulf and wanted to use an Open Street Maps basemap. However, everything in the region is labelled in Arabic, which I can read but most of my target audience probably not. Is there a way to change the labels into English? Or do you know another good open source basemap for the region that I could/should use?

I added quite a few XYZ tile basemaps to my project, they all come out with Hebrew letters (I am in Israel). I overridden the ISR locale with no success. I gues there is a URL parameter that will do the trick but can't find it anywhere.  To clarify, My XYZ tile URL is (nothing mentioning none English): {z}/{x}/{y}.png  and my basemap (Below) has Hebrew labels which I cant use in English manuscript:


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

I have encountered a problem when trying to introduce new people to the SE network: they can't remember Stack Exchange.  So, for example, I might tell a non-tech user: "You should ask your question on this cooking website, it's called cooking.stackexchange.com." They remember the cooking part very easily (or the diy, or gaming, etc..), but they tend to forget the stackexchange part.  So what I propose is that we buy domains for all Area 51 site proposals that end in *.se. So, for example, cooking.stackexchange.com would be magically transformed into cooking.se.  I understand that it isn't a .com but it could be forwarded to *.stackexchange.com    Most (if not all) of the domains should be available since this is a . I'm not 100% sure if non-Swedish compaines/people can register these domains .  This is not the same as  since it proposes we use *.se.com. Also the accepted answer for  was basically that "all sites will get their own .com once they leave beta," which we now know isn't the plan.


This may be the wrong question to ask but, what's the best way to replicate a large load on an asp.net web application? Is there an easy way to simulate many requests on particular pages? Or is the best thing to use a profiler to track a single request and then work out from that if the performance is ok?  It would be good to know how well a web app works with a server spec. I'd like to be able to simulate heavy traffic on my testing server so that I can work out if the production server is good enough (specifically with iis/asp.net not db performance).

Is there a way to test an application where you simulate a hundred different clients connecting to a IIS server and asking the same data? At the customer where our project is running they have 400 computers and they often do stress tests with all computers. I on the other hand have only got my laptop... (and a development server).  (In my case the data is asked through a WebORB Gateway).


How to do dual bootable installation for Acer F5-573G-59V4.

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


On the main desktop site:      On iOS mobile:    Please swap it so the "edited" flair is consistently on the left.

The new attribution style on posts looks great, and brings some consistency with the website which is good. This is how it looks on an iPhone (in landscape, to emphasise the alignment; in portrait both boxes take up the whole screen width):        This is how it looks on the website:        Notice the switched order? That's confusing. Since the app version is aligned left it does make more sense in the order that it is, but since the website version is right aligned and the idea here is obviously consistency with the website could we switch the alignment and order to match?


I have a msi gt70 dragon edition laptop.I want to install Ubuntu, not sure if 14.04lts or the newer 15.04 would be better considering the internal hardware...   i7-4810mq Nvidia GeForce gtx 870m 12 gb ram Steelseries keyboard with programable back lighting ..   Thanks for the input

What are the differences between an Ubuntu Long Term Support release (LTS) and a normal release?


This is a really strange question, I know, but I have a computer here that refuses to boot with any ATi/AMD Radeon card installed.  When any Radeon card is installed in the machine, all fans will spin without issue (and do not stop, even after a period of five minutes), but the board never gives the initial chirp that it is powered up and nothing is ever output to the display.  The machine does not respond to any keyboard input (including toggling num lock) over USB or PS/2, though the desired build uses USB.  Probing the motherboard's power pins show 12V around 12.131V median, 5V around 5.013V median, and 3.3V at exactly 3.30V.  PWR_OK is solid and the total power output hovers around 92W.  When connecting a GeForce, however, the computer immediately boots up, chirps, and displays the Intel logo.  I feel like I'm going mad.  Certainly Intel didn't create a firmware that refuses to work with an AMD graphics card... did they?  Why would this machine refuse to boot with a Radeon card?  Cards that work:   EVGA GeForce 9800GTX+ OC edition (x16) XFX GeForce GTS 250 (x16) PNY GeForce GT 730 (x8)   Cards that don't work:   XFX Radeon HD 5770 (x16) MSI Radeon HD 6450M (x8) XFX Radeon R5 220 Low Power (x16) Gigabyte Radeon R7 240 (x16)   Computer specifications:   Intel DP43TF motherboard running firmware version NBG4310H.86A EVGA 550W power supply (additionally tested all cards on a 600W PSU) Seagate Barracuda 7200.9 LP 1TB disk on SATA port 0 Sony DRU-810A DVD+RW drive on IDE channel 1 6 GB DDR2-667MHz memory in two pairs - 2x1GB, 2x2GB No other PCI or PCI Express cards installed USB keyboard, mouse, and printer If it matters, Dell S2415H 24" monitor over HDMI   Considering the fact that my trusty old overclocked 9800GTX+ works, yet a very low power R5 does not work, it really does not feel power related.  However, I am open to any suggestion, and I may be able to pull a 730W PSU out of a friend's workstation for testing if it would be worth the test.

I have a pretty strange problem here and I would appreciate your help. I recently bought a new graphics card (MSi R9 390 8GB) and a new case as part of an ongoing upgrade to my existing, fairly ancient PC. I transferred all existing components to the new case and it works just fine - that is with all the components as they were in the old case.  When the new graphics card is inserted in place of the old one, I get an error message before I can even load the BIOS; "A bootable device has not been detected" and then a URL for Intel motherboard support. I don't think the GPU is faulty, because I am still getting an image on the screen. So what could it be? Could it be that the motherboard is simply too ancient for this GPU? Am I connecting power to the GPU incorrectly?  Things I have tried, among others:   Resetting CMOS. Using Guru3D to make sure old drivers are deleted. Checked every connector - the computer works exactly as it should with the old GPU in place. Reseated the RAM. Updated motherboard BIOS to latest version. Checked every setting of new BIOS, PCI-E slot is selected, boot drives are in right order. Attempted to boot in safe mode. Disconnected and reconnected every drive between attempting to boot.   PC current specifications:   Intel DP35DP Motherboard Intel Core 2 Duo 2.66GHz CPU Samsung SSD + 2x HDD Drives 4GB RAM Msi R9 390 8GB GPU (new) Msi GeForce 630 GPU (old - working) 750W PSU (within range for GPU and only a couple of weeks old)  Windows 10 Pro 64bit (no install disc available)


in our company I have a few computers that are already Windows 7 clients to a Windows Server 2008 R2 but are now supposed to receive an additional Linux installation as a dual-boot option. The licensing mode on the terminal server is set to "per device" and they have each pulled a license in their windows installation as they're supposed to.  Now how will this be handled by the Terminal Server if I connect the first time via RDP from the Linux OS? We also have 2 Linux Thin Clients who pull a licence just as the Windows PCs do but they only run linux, so its works just fine. I don't want those dual-boot computers to use up 2 licenses.   How is the "per device" policy enforced? Does the server check the computer name for that i.e. would I be able to solve the problem by making sure both OSs use the same computer name?  Please note that I'm asking about the Terminal Server Client Access Licenses (TS CALs) which are handed out to RDP-Clients and "used up".  Thanks a lot for your assistance

This is a  about Licensing.    Questions on licensing are off-topic on Server Fault.  If your question has been closed as a duplicate of this question, then this is because we want to help you understand why licence questions are off topic rather than just telling you "it just is". In all likelihood, this question will not address your question directly, it was not meant to.    I have a question regarding software licensing. Can the Server Fault community please help with the following:   How many licenses do I need? Is this licensing configuration valid? What CALs do I need to be properly licensed? Can I run this product in a virtual environment? Can I downgrade this product to an earlier version? Am I entitled to feature X with license Y?


I'm using Putty SSH client to connect to my Raspberry Pi (w/ Raspbian) from my windows 10 computer. Now that I'm in, I'd like to be able to copy my file from my windows computer's desktop called file.txt, to my Raspberry Pi's desktop. How can I do this?

when calling SCP in PuTTY on my Win7 box, it doesn't let me use C:/, but I also have no idea where on my local machine it will look for files by default. None of program directory or user directory worked. For example, I saved file.txt next to PuTTY.exe, and also in C:\Users\Me but calling SCP file.txt file.txt in PuTTY failed both times with      cp: cannot stat 'file.txt'   So, how do I transfer a file to my server using PuTTY?  EDIT: Also, calling SCP file.txt myserver:file.txt gives a similar error: file.txt: No such file or directory


I was told that numbers under two digits should be written out alphabetically (e.g. one, two, three, four, five, six, seven, eight, nine), and that anything two digits or over should be written out numerically (e.g. 10, 20, 100, 200, 1,400).  Is this best practice, and if so, how come? I feel that it looks better but I'm not quite sure why this is objectively better than writing them all out numerically (e.g. 1, 2, 3, 10, 20, 100 etc.)  Thanks

The junction has a stop sign on each of the four entrances.   The junction has a stop sign on each of the 4 entrances.   The first is preferred, for some reason, by many English texts. Why? I haven't seen this phenomenon in other languages.


I used to be able to rotate upon the origin of any given item that I was working on, but now blender just wants to rotate around the cursor, which i usual have at the world origin. This is a little annoying!! Any ideas or am i missing something? I have searched the web and not had any joy. Tried the full stop, still the rotation is of.

I have a sword that currently rotates around a pivot point thats off of the actual object. Im new to blender and im not sure how i would go about changing it so that the sword rotates around the handle. Any help would be appreciated!


Whenever I comment on a question like to post a fiddle or give more explanation on the problem statement, unless the OP does not mention my name I do not receive the comment what the OP or others might have commented. Can a feature be added for the same as I would be interested in that question and if I had commented from my mobile their should be a way that I get the response for that question.

There has been some discussion about getting notified on comments to questions or answers that don't belong to you, and the long-standing wish to be able to keep track of new answers or developments in questions asked by other people.  Previous discussion in regards to subscribing to questions:                  (very similar to this one)      In regards to subscribing to comments:                    The general feeling - at least here on meta - seems to be against broadening the notification rules, out of fears of useless notifications to flood users' inboxes, turning SO into more of a discussion forum than it should be, etc.   Here's a suggestion that would keep the user 100% in control what they get notified about, not generate any notifications by default, and require only minimal modifications to the User Interface.  Each question and each comment area would get an envelope symbol.    it is inactive (=white) by default.  When those envelopes are hovered over, the tooltip says click to subscribe or something.  When clicked on, the envelope lights up in green or some other colour (but different from the actual notification envelope's orange to avoid confusion.) You are then subscribed to any updates to that question or comment thread.    For each subscription, you receive notifications in the "responses" tab, as if you were the owner of the comment or question.     To unsubscribe from a question or comment thread, you open the page, and click the green envelope. It turns back white, and the notifications disappear from your responses tab (if technically possible - otherwise, there just won't be any new ones added.)    No further functionality, like managing subscriptions or anything, is necessary IMO. If the flood of notifications from a subscribed question starts to annoy you, you just open it and unclick the envelope. Done.   It would make it possible to leave a comment to a newbie's question and make sure their answer reaches you even if they don't know they need to address you using @username You could subscribe to those "oh, I'd like to know the answer to that" questions and receive active notification, instead of them getting forgotten in your favourites list You could subscribe to discussions you are interested in the outcome of, but don't want to participate in. It would (in my opinion) sort out a number of woes aired by many users in a good way, without adding annoyances to those who like the system just fine the way it is. It would not require a change in the visible layout. As far as I can see, the space the envelope would need to be is empty everywhere.   I don't know SO under the hood of course, but technically, the system would be doing what it's doing already, notify question owners of updates - just that the circle of internal "owners" would grow.


I make a html page. I want load step by step in page with jQuery but I don't know make it.  My HTML code:

   Fade-in burst in sequence!

I am trying to find a way to load a JSON page to display my content, which I currently have. But I am trying to fade in each element one after another? Is anyone familiar with a way to do that?  Fade in each element with a slight delay?  Here is an example of my code, I am using the jquery framework.  CODE:


I am a newbie with openldap 2.4 and I need to restrict read access to anonymous. Actually, if someone write ldapsearch -x -H ldap://myipaddrr he can see all entries of my HDB database.  How can I solve this using cn=config (dynamic configuration). By default there is a lot of olcAccess setup...  thank you

With slapd.conf you could globally disable anonymous binding and require authentication with the following static directives:  disallow bind_anon require authc   How can I achieve the same global settings, but using the new cn=config live configuration method?


How can I hide the /node page in Drupal 8?   This site:  describes the reasons for hiding it and the process for Drupal 6 and 7, though no information for Drupal 8 now  has been removed.

In other words, what is the Drupal 8 equivalent of ?  Drupal 8 still uses hook_menu(), but for what I can see, the information returned by the hook is different from what the hook returned in Drupal 7. For example, the definition given in user_menu() for user is the following.    $items['user'] = array(     'title' => 'User account',     'title callback' => 'user_menu_title',     'weight' => -10,     'route_name' => 'user_page',     'menu_name' => 'account',   );   The route_name property links to an entry in the  file.  user_page:   pattern: '/user'   defaults:     _content: '\Drupal\user\Controller\UserController::userPage'   requirements:     _access: 'TRUE'   This is different from what done with Symphony, and it confuses me about how a module can alter the route defined from another user.  The only function that is still invoking hook_menu_alter() is menu_router_build(), but that function still contains code that needs to be updated, since it is still using the now deprecated drupal_alter().    // Alter the menu as defined in modules, keys are like user/%user.   drupal_alter('menu', $callbacks);   foreach ($callbacks as $path => $router_item) {     // If the menu item is a default local task and incorrectly references a     // route, remove it.     // @todo This may be removed later depending on the outcome of     // http://drupal.org/node/1889790     if (isset($router_item['type']) && $router_item['type'] == MENU_DEFAULT_LOCAL_TASK) {       unset($callbacks[$path]['route_name']);     }     // If the menu item references a route, normalize the route information     // into the old structure. Note that routes are keyed by name, not path,     // so the path of the route takes precedence.     if (isset($router_item['route_name'])) {       $router_item['page callback'] = 'USES_ROUTE';       $router_item['access callback'] = TRUE;       $new_path = _menu_router_translate_route($router_item['route_name']);        unset($callbacks[$path]);       $callbacks[$new_path] = $router_item;     }   }


In the UK, there are several third-party services which consume data produced by Network Rail regarding the operational rail timetable and live train movements. These services produce data which are highly informative regarding my journey. For example, I often use such services to determine where a train originates, from which inbound service it was formed (if applicable), and to ascertain the timeliness of the service when en route. I am a particular fan of .  Are there any equivalent services for Deutsche Bahn trains? I'm aware of the , but am looking for a service which provides textual timetable information regarding train formation and intermediate passing points, rather than a graphical readout.  My current motivation is to search for the train I am shortly due to board in Brussels; the online timetable indicates it is delayed, and I wish to determine whether the train originates here and, if so, from which inbound service it forms, so I can determine whether it is likely to be in the platform already.  It would be particularly great if there was a service worked across borders into other Western European countries where DB long-distance services operate, but I can understand this is perhaps unlikely due to the cross-border data sharing required between the various network operators.

I am looking for a website like flightradar24 but for trains, or I like to follow more precisely where my train is than the limited "next departures/arrivals" information that is readily available.  Where can I find such information?


I want to generate a string-code for the user that represents his progress in the game (so he can load this state somewhere else). I don't want him to be able to guess the system and thus load a state which he hasn't yet achieved.  The following variables are involved:   A number X between 1-30 representing the highest level he unlocked. For each level lower than X a boolean representing whether he made the level on hard or not. For each secret object he could have found (also roughly 30) another boolean.   My idea was to just build a binary number from all these but that's just way too easy for the user to hack. If he beats level 1 and then saves, he will see his code being something like 0x1, while having bet level 10 will be something like 0x200.

How would I make a password system for a single-player game like the ones used in older console games?  For example, Mega Man X saves work by giving you a series of numbers that you can enter later to load your save.


I'd like to use the new San Francisco font on a site. I've tried:  font: 'San Francisco', Helvetica, Arial, san-serif;   to no avail. I have tried the answers to , but @font-face is not the solution here.

Is there a way to add some custom font on a website without using images,  or some other graphics?  For example, I was working on a wedding website, and I found a lot of nice fonts for that subject. But I can't find the right way to add that font on the server. And how do I include that font with CSS into the HTML? Is this possible to do without graphics?


i was working on emoji input for textarea which is contain to   const emojis = [0x1F557, 0x1F4A2, 0x2764, 0x1F49D, 0x1F498, 0x1F497, 0x1F496, 0x1F495, 0x1F494, 0x1F493, 0x1F44B, 0x1F445, 0x1F444, 0x1F64F, 0x1F64C, 0x1F64A,                    0x1F649, 0x1F648, 0x1F637, 0x1F635, 0x1F633, 0x1F632, 0x1F631, 0x1F630, 0x1F62D, 0x1F62B, 0x1F62A, 0x1F629, 0x1F628, 0x1F625, 0x1F624, 0x1F623,                 0x1F622, 0x1F621, 0x1F620, 0x1F61E, 0x1F61D, 0x1F61C, 0x1F61A, 0x1F618, 0x1F616, 0x1F614, 0x1F613, 0x1F612, 0x1F60F, 0x1F60D, 0x1F60C, 0x1F60B,                 0x1F60A, 0x1F609, 0x1F606, 0x1F605, 0x1F604, 0x1F603, 0x1F602, 0x1F601];  So let's say we have textarea for chat contain to <textarea name='message'>Good morning 😍</textarea>  while we in mysqli query part we will do something like $usermsg = htmlspecialchars($_POST['message'], ENT_QUOTES, 'UTF-8');  OR $usermsg = htmlspecialchars($_POST['message']);  so the output is going to be Good morning ????  i know we most use PDO / prepare statement to avoid Sql injection but right know we are in mysqli any solution / advice to keep emoji's stored in database while we using htmlspecialchars to keep us save from xss etc.. ?

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


Any comments on the usage of "a good knowledge in English"?

She tried to figure out how much knowledge my class had of the real Pocahontas.    Should I use of or on there?


please solve the initial value problem $dy/dx=2y^{1/2}$, y(0)=a. I wanted to know that this  problem admits infinitely many solutions for a=0 or admits infinitely many solutions for $a\geq 0$

Show that the first order differential equation $y'(x)=\sqrt{|y(x)|}$ with intial value $y(1/2)= 1/16$ has infinitely many solutions on the interval [−1, 1].  My thought were to show that this equation has two solutions (just by ansatz, or just looking at the interval $]0, 1]$ to get $y'(x) = \sqrt{|y(x)|}$) and deduce from that that there must be infinitely many solutions since the solution set forms a vector space. I've got a nagging feeling this isn't the way to go though. Can anybody give me a hint where to look?


According to this question:      It is the energy, and thus the frequency of a photon $E=hf$, that determines where it lies in the electromagnetic spectrum (for example its color). Wavelength is determined by the index of refraction of the medium it is travelling through via $λ=v/f$.    Does this mean that a photon would appear red in color regardless of how short or long its wavelength is, so long as its energy corresponds with that of red light??? Does this mean an x-ray or gamma-ray or radio wave is still what it was initially despite of a substantially different wavelength?  For example if you pass a red light through something with an extremely high $n$ such that $v=1 \times 10^{-6}\:\mathrm{m/s}$....

What determines the color of light -- is it the wavelength of the light or the frequency?  (i.e. If you put light through a medium other than air, in order to keep its color the same, which one would you need to keep constant: the wavelength or the frequency?)


At first I would like to apologize to the members who answered .  question had considerable information so  I asked different question.   Actual question I wanted to ask,  We know that $$\int (x + b)^n\,\mathrm dx =\frac{(x+b)^{n+1}}{n+1} + C$$  so while solving $$\int x^2\,\mathrm dx = \frac13x^3 + C$$  also, $$\int (x + 3)^4\,\mathrm dx = \frac15(x + 3)^5 + C$$  but for trig functions like,  $$\int \sin^2x\,\mathrm dx \neq \frac13\sin^3x + C$$  Instead, we have to simplify it first algebraically. So why does the intuition fail here?  I apologize once again. But still I learnt some new things.

We know that $$\int f(ax + b)\,\mathrm dx = \frac1aF(ax + b) + C$$  so while solving $$\int x^2\,\mathrm dx = \frac13x^3 + C$$  also, $$\int (x + 3)^4\,\mathrm dx = \frac15(x + 3)^5 + C$$  but for trig functions like,  $$\int \sin^2x\,\mathrm dx \neq \frac13\sin^3x + C$$  Instead, we have to simplify it first algebraically. So why does the intuition fail here?  Update: I seem to be confused with f. Till now $$\int \sin^2(1*x+0)\,\mathrm dx  \ $$, I have assumed f = (sin(x))^2 with a=1 and b=0. There seems something wrong with my understanding.


I've been trying to install Ubuntu 16.04 in VirtualBox (Windows 7 host), but keep running into the same problem regardless of what I tweak in the vm's settings:    This is the second time I've installed Ubuntu. The first, using the same .iso, ran into the same issue but eventually succeeded (wish I could remember what I did), but I deleted the first machine because I didn't know any better and wanted to have more memory for it.   What's even happening?

I installed  on VirtualBox. I logged in, installed VirtualBox additions and restarted the system. The system did not load again, instead I see this:    The aspect ratio of the image is preserved in this screenshot and it doesn't make much sense to me - no screen has such dimensions. I did not do anything else special that I could mention. This is the only thing I see before the screenshot above:


Show there doesn’t exist a non-constant polynomial $p(x)$ with integer coefficients such that $p(x)$ is prime for all non-negative integers $n$.   There is a hint: note in particular that $p(0)$, the constant term of $p(x)$, is prime.

I recently encountered this following proposition:  For every polynomial, there is some positive integer for which it is composite.  What is the most elementary proof of this?


I am learning about multithreading in C#. It is making me hard, so I am doing some simple programs to understand it better. I realized that if I have:    static void Main()     {         Task[] tasks = new Task[4];         for (int i = 0; i < 4; i++)         {             tasks[i] = Task.Factory.StartNew(() => {                 Console.WriteLine(i);             });         }         Console.ReadKey();     }  The output is 4444, no 0123 like I expected. Why is it? EDIT: Sadiq said in his answer that the reason of this behaviour is because i'm closing over a loop variable. But if I add to my code Thread.sleep(500); outside the lambda statement and inside the loop, I get 0123. So, why this behaviour supposedly caused by clousures don't occurs with adding this line of code? it seems to me that the reason of the asked behaviour is other. The code for if you don't understand what I've just written: static void Main()     {         Task[] tasks = new Task[4];         for (int i = 0; i < 4; i++)         {             tasks[i] = Task.Factory.StartNew(() => {                 Console.WriteLine(i);             });             Thread.Sleep(500);          }         //Now the output is: 0123         Console.ReadKey();     }

I met an interesting issue about C#. I have code like below.  List<Func<int>> actions = new List<Func<int>>();  int variable = 0; while (variable < 5) {     actions.Add(() => variable * 2);     ++ variable; }  foreach (var act in actions) {     Console.WriteLine(act.Invoke()); }   I expect it to output 0, 2, 4, 6, 8. However, it actually outputs five 10s.  It seems that it is due to all actions referring to one captured variable. As a result, when they get invoked, they all have same output.  Is there a way to work round this limit to have each action instance have its own captured variable?


I have been trying to take photographs of items in the mid-ground and am not getting sufficient blur on my foregrounds and backgrounds. I have tried using different distances between my subjects, adjusting my f-stops and I am only getting a slight blur effect at best.

I have a compact digital camera, and in macro mode I can manage to achieve a blurred background, if the background is far enough away. Can this be done when taking non-macro pictures, and if not, is there a way to simulate it?  When I shoot portraits with my brother's DSLR, it is quite easy to fade out the background. But with my point and shoot camera, I haven't been able to take such photos.   I choose a large aperture for my camera but it still doesn't work. I know that standing further and zooming will result in a smaller depth of field, but it doesn't seem to be enough to get the really nice "bokeh" look. I've tried macro mode, and that will work if the subject is close enough and the background far enough away, but how can it be done with non-macro pictures?   Why are DSLR cameras are so much better in this area? What are the general recommendations to do this using a compact or super-zoom camera?


I have three Ubuntu VM on Microsoft Azure. Every-time I login (through ssh) on my VMs in the Azure I see the following hint: * Kubernetes 1.19 is out! Get it in one command with:   sudo snap install microk8s --channel=1.19 --classic  I know Kubernetes is for resource manager But I didn't install Kubernetes in my VMs. What does it mean when I login in my VMs on Azure?? How I must to do??

When I ssh into my Ubuntu box I see the output below. I was surprised to see the quote and the link to the TechRepublic article. Is that an advertisement? Anyone know where that is coming from? Is there any way to remove that? Thanks, Ben Welcome to Ubuntu 20.04 LTS (GNU/Linux 5.4.0-37-generic x86_64)   * Documentation:  https://help.ubuntu.com  * Management:     https://landscape.canonical.com  * Support:        https://ubuntu.com/advantage    System information as of Sun 21 Jun 2020 10:06:54 PM PDT    System load:  0.05                Processes:                249   Usage of /:   43.6% of 227.74GB   Users logged in:          0   Memory usage: 8%                  IPv4 address for enp0s25: <redacted>   Swap usage:   0%                  IPv4 address for wlp2s0:  <redacted>   Temperature:  56.0 C   * "If you've been waiting for the perfect Kubernetes dev solution for    macOS, the wait is over. Learn how to install Microk8s on macOS."     https://www.techrepublic.com/article/how-to-install-microk8s-on-macos/  0 updates can be installed immediately. 0 of these updates are security updates.


THE SOURCE: LOST (tv series)      LOCKE: You told her not to talk to me. That made her pointless... Now, Charles, it's clear you're not afraid to die. So, there's only one way to motivate you to tell me what I want to know. Soon, this will all be over. I'll get what I want. And I'll finally leave this island. And when I do, the first thing I'm going to do is kill your daughter...Penny.   Why the writer did use “kill” instead of killing   Killing you daughter is the first thing I am ...

All he does is watching TV.   I said this sentence and my native friend corrected me and said 'you need to use bare infinitive here'      All he does is watch TV.   Why is this right while the other is false? If I change the placement of the complement and subject, I will have this sentence:     Watch TV is all he does.   Shouldn't it be 'watching TV (or to watch) is all he does'?  I searched for it online and I couldn't get anything. Is there a rule that I'm missing? When do they use bare infinitive after 'to be' verbs?  Thanks


I have the following problem:  I have a button like: <button id="button_show_countries" >Start</button> in the index.html and a click event in the view.js:          $("button#button_show_countries").click(function() {             debug('View Click Event triggered: notice the Controller that the user wants to see the Interests data');             Controller().countrieslandscapeasked();         });   This wokrs very well. Now I create with the view a button. This button I add to index.html. The button looks like:     <button class="insertButton" type="button" id="insert_button_0">insert here</button>   and in the view is also an eventlistener for this:  $("#insert_button_0").click(function() {             debug('Data should be add at Position 0');          });   But when I click on the button the event is not "fired". What is wrong with my code? :/  The button work, if I add him at the beginning like the show countries button.  Is it problematic that I add the button dynamically at runtime?  Thanks for help.

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


I ran the command sudo apt-get install update and as you can see my results below:  cyberwizard34@Hogwarts:~$ sudo apt-get install update [sudo] password for cyberwizard34:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package update

When I log into my web server via SSH I see the information:  88 packages can be updated. 80 updates are security updates   I tried apt-get update then apt-get upgrade but each time I log in I still see the message about updates. How do I install them?


How to prove the following equality? $$\sum_{n=1}^{\infty}\frac{1}{\prod\limits_{k=1}^{m}(n+k)}=\frac{1}{(m-1)m!}.$$


I wan't to make a program that logs keys. But is it possible to do this when the program is not focused? I only know how to do this when the program is focused.  Log keys when program is focused with pygame:  import pygame from pygame.locals import * import sys  pygame.init()  width, height = 300, 300  display = pygame.display.set_mode((width,  height))  while True:     for event in pygame.event.get():         if event.type == QUIT:             pygame.quit()             sys.exit()         if event.type == KEYDOWN:             print chr(event.key)

I'm looking for ways to watch mouse and keyboard events on Windows, Linux and Mac from Python.  My application is a time tracker. I'm not looking into the event, I just record the time when it happens. If there are no events for a certain time, say 10 minutes, I assume that the user has left and stop the current project.  When the user returns (events come in again), I wait a moment (so this doesn't get triggered by the cleaning crew or your pets or an earthquake). If the events persist over a longer period of time, I assume that the user has returned and I pop up a small, inactive window where she can choose to add the time interval to "break", the current project (meeting, etc) or a different project.  I've solved the keylogger for Windows using the .  On Linux, I have found a solution but I don't like it: I can watch all device nodes in /etc/input and update a timestamp somewhere in /var or /tmp every time I see an event. There are two drawbacks: 1. I can't tell whether the event if from the user who is running the time tracker and 2. this little program needs to be run as root (not good).  On Mac, I have no idea, yet.  Questions:   Is there a better way to know whether the user is creating events than watching the event devices on Linux? Any pointers how to do that on a Mac?


I am just analyzing my logwatch logs, and I see the following entries:   SMTP SESSION, MESSAGE, OR RECIPIENT ERRORS  ------------------------------------------   Mail Rejected:        Total:  6   Mail Deferred:        Total:  229   Total SMTP Session, Message, and Recipient Errors handled by Sendmail:  235   ---------------------- sendmail End -------------------------   I only use sendmail for logwatch, so what is causing all these errors, and especially, what are deferred emails.


Let $x,y$ be distinct real numbers greater than $0$. Prove       $$x^x+y^y>x^y+y^x .$$   Source: I think it comes from a Russian test given in 1991, but I haven't been able to verify this.

Let $x,y$ be positive numbers. Prove that $x^x+y^y \ge x^y +y^x$.   This question appeared in Summer 1991 Russian Olympiad team test. Apparently, I tried to come up with different approach such as Jensen, Karamata's inequality and nothing works so far. I just need a discussion here. Hints are not necessary.


From The Cat in the Hat,     I sat there with Sally. We sat there, we two. And I said, "How I wish we had something to do!"    How do modern linguists, eg CGEL authors or readers, characterize how We sat there, we two differs from the more basic or standard We sat there or We two sat there or The two of us sat there.   I know why, primarily, the variant choice was made by the author here. But it's an example of what? Are there common reasons to choose it aside from creating rhyme or emphasizing/stressing the subject?   I can think of simple similar constructions such as We lived in our own world, you and I. And I can see a relationship between such and emphatic pronouns or emphatic reflexive pronouns or similar: I made it myself.   There is also something similar and something different between the instant sentence and, for example, We sat there, we did.   My purpose in asking is to acquire language to help me make a point that what may seem like very basic or "low level" text usually contains relatively complex formations. CGEL pages or chapter would suffice to answer the question for my particular needs, and I'm hoping for an answer that, if elaborate, also contains a concise and fairly general summary, but which uses technical linguistic terms.

Is it now considered acceptable to follow a proper noun ... or any noun ... with a pronoun? E.g.      The President he issued a new executive order.


During the period between January and today, I have added many changes to my resume that i want to make an employer noticed of. I doubt between 'have done' and 'had done'.     " I would like to inform you that some changes have been brought to my resume from   the first time I had contacted you through your website(January 2014) "      Or      " I would like to inform you that some changes have been brought to my   resume from the first time I have contacted through your website(January 2014)"   Please to help me resolve the problem i have with past usage once and for all, any link or doc is highly appreciated.

Non-native speakers often get confused about what the various tenses  and aspects mean in English. With input from some of the folk here I've put together a diagram that I hope will provide some clarity on the matter.  I offer it as the first answer to this question. Consider it a living document. Input is welcome, and good suggestions will be  incorporated into the diagram.    Nota bene: What this is not is a discussion of whether there are  more than two tenses in English. , to which this question is not intended to supply arguments one way or the other.  Here, the aim is to provide an overview of what constructions English-speaking people use for conveying information about actions referring to past, present, and future, and to provide it first and foremost to precisely the people who are likely to use "tense" as a catch-all term in their search, rather than to linguists who know better.  Breaking News There is now an excellent ELU blog article titled  . It is highly recommended reading.


Evaluate the following limit without using L'Hospital method  $$\lim_{x\to1}\left\{\frac{9}{x^9-1}-\frac{5}{x^5-1}\right\}$$ My turn is $$L=\lim_{x\to1}\left\{\frac{9(x^5-1)-5(x^9-1)}{x^{14}-x^9-x^5+1}\right\}$$ $$L=\lim_{x\to1}\left\{\frac{9(x^5-1)-5(x^9-1)}{(x^{14}-1)-(x^9-1)-(x^5-1)}\right\}$$ then divide the numerator and the denominator by $$x-1$$ But I got again $$\frac{0}{0}$$

How does one evaluate the following limit? $$\lim_{x \to 1} \left(\frac{23}{1-x^{23}}-\frac{11}{1-x^{11}} \right)$$ The answer is $6$.  How does one justify this answer?  Edit: So it really was just combine the fraction and use L'hopital's rule twice (because function and its first derivative are of indeterminate form at $x=1$). This problem is more straightforward than it seems at first.


I would like to get back into cycling again, however over the last couple of years I have piled a few needless pounds on. I currently weight 178kg (392 lbs), would a standard bike frame withstand my weight? I'm hoping to loose substantial weight hopefully by cycling each day as I've never been much of a runner. But do I need to loose this weight before I start cycling. I had been looking at the Carrera Vengeance Mens Mountain Bike 2015 - 22".

A few years ago, I've bought  (see edit) bike. At that time I was around 90 kgs and I didn't have any problems.  Today I'm around 120 kgs and I was considering (among other things) starting cycling again. Is this bike "good" enough to carry me? What should I expect? Any tips?  EDIT! Apparently, Drag have renamed some of their bikes in the last few years, so the above information is a bit wrong.  seems to be my bike. At first I didn't recognize much difference, but this one has suspension on the front which mine also has. Does this change anything


My is there sound in this world whenever two (or more) things collide with each other?  Examples   When two cars collide When something with enough mass falls from a height When small drops of water fall into the any water container   There are so many things associated with a collision; why is Sound one of them?  This question is related to Earth’s atmosphere only, not vacuum.  This question is for sound related to collisions only. No vibrations.

When two objects collide and undergo a partially inelastic collision (so every one we experience in every-day life), they rebound to a certain degree, but kinetic energy is not conserved. Thus, the energy of motion must be converted to another type of energy. Thus, when two object collide, the most common forms of energy that kinetic energy is converted to are sound energy and thermal energy.   Some collisions are louder than others just because they cause a bigger local variation of pressure (which then propagates through air until finally gets heard). So, why some objects, even if the velocity before and after the collision seems to be the same, are louder than others? I mean, how do the different material properties enter in the phenomenon?  How and why, by means of solid and fluid mechanics or with an heuristical microscopical reasoning, can this process be explained?


How to write a SQL to combine data from multiple columns and rows into one row.  OrganizationId  Name    Type    Active --------------------------------------       1         Baker   County  Yes       2         curry   county  Yes   Expected result:  SomeColumnName ------------------------------- 1BakerCountyYes2currycountyYes

I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life).  In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently.  group_concat, by the way, does this: given a table of, say, employee names and projects...  SELECT empName, projID FROM project_members;   returns:  ANDY   |  A100 ANDY   |  B391 ANDY   |  X010 TOM    |  A100 TOM    |  A510   ... and here's what you get with group_concat:  SELECT      empName, group_concat(projID SEPARATOR ' / ')  FROM      project_members  GROUP BY      empName;   returns:  ANDY   |  A100 / B391 / X010 TOM    |  A100 / A510   So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat?   I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :)


I have a very big text file ~ 105 G it's includes a lot of <XXXX> (angle brackets including text in between).  I want to remove those brackets and text in between.

I have a file as below:  mime PI Name: ISHO SUCCESS RATE RT, Value: 95.663826 scr  PI Name: RRC Access Failures due to UU, Value: 0.13394141 prog PI Name: RRC Access Failures due to UU, Value: 0.16077702 sch PI Name: RRC Access Failures due to UU, Value: 0.11781933   I want to remove text PI till Value:. I tried   sed '/<PI>/,/<\/Value:>/d'    Any help?


I am about to finish my Ph.D. in civil engineering, I would finish it by the age of 28. I don't like my field that much and was pushed to pursue it from the beginning (at that time, was very confused and did not know what I want / I need and that is a huge problem in my personality, so my father pushed me to pursue it even though I did not like it at all !). (one could ask why did you pursue a PhD in a field you don't like; the answer is pretty simple; it was the only way to get out of a third-world country :D) seeing the big-fat salaries of data scientists/machine learning engineers around the world makes me jealous sometimes and makes me super unsatisfied with the work/research and the field I am pursuing. I am really considering getting some undergraduate courses once I finish my current Ph.D. and start applying for CS masters. I will try to apply for double grants also, don't know if my current Ph.D. could help get those grants which will make me financially comfortable pursuing research in other fields again. Also, I want to pursue a Ph.D. in machine learning cause I see the salaries are fatter for those dudes; I don't like academia and I don't like research and I really do hate teaching but I am used to doing a lot of things I don't like. What are your perspectives?

I am studying a combined bachelor of engineering (electrical) and bachelor of mathematics; I just started this year and will graduate in 2018. The reason why I am doing double degrees and not a single degree is because I love both electrical engineering and mathematics and I could not ignore any of them. So with this in mind, I am thinking of doing two PhDs when I graduate (one in electrical engineering and one in mathematics). Is this a good path or I should concentrate on only one of them?