Let $U_i$ be i.i.d Uniform(0,1) random variables, and let $X_{(1)},\dotsb, X_{(n)}$ the order statistics of the random variables. Then find distribution of $Y = U_{(n)} - U_{(1)}$. I used two methods to solve this problem.   Using joint pdf of order statistics  we know pdf of $(X_{(r)},X_{(s)})^t$ $(1 \leq r<s \leq n)$ is $f_{X_{(r)},X_{(s)}} (x,y) = {n! \over {(r-1)!(s-1-r)! (n-s)!}}[F(x)]^{r-1}[F(y)-F(x)]^{s-1-r}[1-F(y)]^{n-s}f(x)f(y)$ So, $f_{X_{(1)},X_{(n)}}(u_1,u_n) = {n! \over {(n-2)!}}(u_n - u_1)^{n-2} I_{(0<u_1<u_n<1)}$ Let $X \equiv X_{(1)}$ and $u : \begin{cases}X = X_{(1)}\\Y = X_{(n)} - X_{(1)}\end{cases}$, $u^{-1} :\begin{cases}x_{(1)} = x\\x_{(n)} = x+y\end{cases}$ , u : one to one , $\vert det( {\partial(x_{(1)},x_{(n)}) \over {\partial (x,y)}}) \vert = 1$ $\therefore f_{X,Y}(x,y) =f_{X_{(1)},X_{(n)}}(u_1,u_n)\vert det( {\partial(x_{(1)},x_{(n)}) \over {\partial (x,y)}}) \vert = n(n-1)y^{n-2} I_{(0,1)}(x) I_{(0,1)}(y)$ $\therefore f_Y(y) = \int_{0}^{1} f_{X,Y}(x,y) dx = n(n-1)y^{n-2} I_{(0,1)}(y)$    Using Beta distribution  We know $X_{(r)} \sim Beta(r,n-r+1)$ So, $X_{(n)} \sim Beta(n,1),X_{(1)} \sim Beta(1,n),Y = X_{(n)} - X_{(1)} \sim Beta(n-1,2)$ $\therefore f_{Y}(y) = {\Gamma(n+1) \over {\Gamma(n-1) \Gamma(2)}} y^{n-2} (1-y) I_{(0,1)}(y) $  I don't understand why the results of these methods are different. I don't know where I got it wrong, can you help me please?

Let $X_1,...,X_n$ be iid as $U \sim [0,1]$ with pdf $f(x) = 1(0 <x< 1)$. Determine the range distribution.   I have managed to determine the distribution of the minimum and the maximum, however I cannot/do not know how to determine the distribution of range.   Minimum:  $f_N = n(1-x)^{n-1}$ and maximum $f_M= nx^{n-1}$   I am aware that the calculation of range distribution is based on convolution: $f_R=\int f_{N,M}(x,x-r)dx$, However I cannot get the correct result, which according to my lecture slides is : $f_R= n(n-1)r^{n-2}(1-r)$  Could someone break this down for me ? My math background is not great


If i have a text file with the line qwertyuiop, how can i select the first character and after that each characters by jumps of 2 without using more than 1 pipe in my command ? In qwertyuiop i would have qetuo printed in the cmd.

This line of code does exactly this except I want it to start at the first character not the 7th. $ echo 1234567890abcdefghijklmnopqrstuvwxy | sed 's/.\{1,7\}\(.\{0,1\}\)/\1/g'  What I'm looking for is 19gow


If I have a range $x \to y$ and I want to map it to $x' \to y'$, what is the logic behind the mapping process? I found the formula online as:  $$R = (y' - x') / (y - x)$$  $$\text{output} = (\text{input} - x) * R + x'$$  I understand that $R$ is the ratio of both ranges, but I don't understand the second part where we subtract $x$ from the input? Why do we do this, I can't seem to wrap my head around this.

I'm stuck in a problem of mapping numbers from one range to another. I want to calculate popularity of a web page based on the number of page hits on a scale of 10. The problem is total number of web pages are around 41,00,000 and the web pages for which page visit is given are only 1,70,000. Also, the page visit for a web page is between 20,000 and 1.  Now, I'll try to rephrase the above problem in more mathematical problem, I have 41,00,000 objects for which I need to calculate some factor "po". Out of these 41,00,000 objects, 1,70,000 objects contain some number 20,000 <=y <= 1. Now how can I calculate "po" for each object on scale of 10.  The data mostly looks like,  O1: 20,000 O2: 17,000 O3: 16,000 . . . . . . . O19: 334 O20: 300 . . . . . . . On: 1 and so on......   Mostly, objects have page visits = 1.  I tried calculating page visit for each object/maximum page visit for an object but that gives me very small values(like 1/20,000 is a very small number). I want my resulatant po values to be at some distance from one another so that I can differentiate between them.  Can anyone please suggest me some solution ?  Thanks


How do i make python listen for changes to a folder on my desktop, and every time a file was added, the program would read the file name and categorize it it based on the extension?  This is a part of a more detailed program but I don't know how to get started on this part. This part of the program detects when the user drags a file into a folder on his/her desktop and then moves that file to a different location based on the file extension.

Is there a function to extract the extension from a filename?


Given $R$ a commutative ring and $I,J$ ideals of $R$, such that $I+J=R$, show that $I^m+J^m=R, \forall m \geq 1$   My problem is that I don't know what is the meaning of $I^m$ and in literature I didn't find anything. I know that, given $A,B$ ideals, then $AB= \{ \sum_{i=1}^n a_ib_i |a_i \in A, b_i \in B, n \in \mathbb{N} \}$, but with this notation $I^2=II=I$, so what is the meaning of $I^m$? It could be $I^m = \{ x^m | x \in I \} $?

Let $R$ be a commutative ring and $I_1, \dots, I_n$ pairwise comaximal ideals in $R$, i.e., $I_i + I_j = R$ for $i \neq j$. Why are the ideals $I_1^{n_1}, ... , I_r^{n_r}$ (for any $n_1,...,n_r \in\mathbb N$) also comaximal?


I know there're some other articles talk about how to simulate ternary operator in Python, but my question here is not how can I simulate it, but why do these ways work.  As we all know simulating a ternary operator (condition: if_true ? if_false) is done by  a if condition else b   However, there're at least two other ways to accomplish that, e.g.  (if_false, if_true)[test]   and  (expression) and (if_true) or (if_false)   Example would be  (4, 5)[4 > 5]   gives 4  4 > 5 and 4 or 5   gives 5

If Python does not have a ternary conditional operator, is it possible to simulate one using other language constructs?


I am trying to write a regular expression to get all occurrences of the pattern !\d+ that are not between specific HTML tags.  Example input (available on ):  bla bla !1234 abcd
 every occurrence here should be ignored !12345 but it is not
 here should be captured !54321 but
 here it should be again ignored !76453
 and here again captured !123456   I tried this RE:  (?:<(?P<tag>code|pre)>.*?<\/(?P=tag)>)?(?!<(code|pre)>)*!(\d+)   The logic is this:   (?:<(?P<tag>code|pre)>.*?</(?P=tag)>)?: capture all text between the relevant tags in the first part of the RE, so that if the pattern appears between the tags, it will be consumed by this RE (?!<(code|pre)>)*: Make sure there are no other opening tags between the first part of the RE and the required pattern !(\d+): Match the pattern and grab the number   This does not seem to work, and I don't quite understand why. Numbers between tags are still matched. Why is that?  Thanks.

I want to grab the value of a hidden input field in HTML.  <input type="hidden" name="fooId" value="12-3456789-1111111111" />   I want to write a regular expression in Python that will return the value of fooId, given that I know the line in the HTML follows the format  <input type="hidden" name="fooId" value="**[id is here]**" />   Can someone provide an example in Python to parse the HTML for the value?


I have the following string :   a = "/home/user/Downloads/repo/test.txt"   My goal is just to create a string which contains only test, hwo can I do this ?  actually a comes from   f = tkFileDialog.asksaveasfile(mode='w', defaultextension=".txt")   and a is equal to a = f.name  but I realized f.name does not give me just the name of the file.

How to get the filename without the extension from a path in Python? For instance, if I had "/path/to/some/file.txt", I would want "file".


I have a 2 in 1 laptop that allows me to use the touchscreen for painting with a stylus. The biggest pain I have right now is that whenever I'm in tablet mode I don't have access to the keyboard for Undo/Redo operations besides using the menu for edit > Undo. What I'm looking for is something like Artistpad from Tablet pro which has the feature I'm looking for, however it stands separate from blender, takes up a large part of the screen, and is too expensive for how little of the features ill be using. See picture below for example. Is there some sort of history browser, custom toolbar or gizmo maker that I can use within blender to add a button onto the viewport to let me undo/redo? Would this be possible via scripting?

I was watching this  on making a custom UI tab using Python, and in the line from bpy.types import Menu, Panel, UIList, I see the names of objects that look like they can all be used to make different UI elements. Does bpy.types contain all the objects that people use when they want to make custom UI elements?


Could the Borg have been a result of a civilization in the Delta Quadrant trying to develop advanced medical nanites and the experiment went awry?

Was there any explanation of the origin of the Borg from Star Trek?  I've seen most of the TV shows but not read any books - is it explained there?


I'm not going crazy or anything but after I hibernate my PC it just decides to turn back on again without me doing anything. I have checked my BIOS and it shows nothing that will turn it back on.  Any suggestions on what I should check?

After clicking sleep or hibernate in Windows 7, my computer loads for a while and then goes into sleep mode, but not 1 second later it powers back up. The event log has no errors and no warnings appear when it comes back out of sleep/hibernation.  Here's my system specifications:    Windows 7   I believe this is all that's relevant. I've installed the latest chipset drivers, but I'm unable to update my BIOS (but this is another matter; maybe because the motherboard in the  is different).  I've also tried turning off the "Allow this device to wake up my computer" for the network card, keyboard, and mouse -- but this makes no difference.  If flashing the BIOS is the only thing that will fix this, then I will create a new question to this effect.  Maybe I should change the suspend mode from S3 to S1?


Is there any function, $f(x)\neq x$, for which $f(f'(x))=f'(f(x))$?

I am wondering whether or not there is a reasonable characterization of differentiable functions $f: \mathbb{R}\to \mathbb{R}$ such that $f'(f(x))=f(f'(x))$ for each $x\in\mathbb{R}$. (Or, if you like the composition sign, $f'\circ f=f\circ f'$).   I could only come up with trivial examples of such functions: $f(x)=0$ and $f(x)=e^{x}$.   This reminds me of a recent Putnam problem (2010), which asked whether or not there exists a strictly increasing function $f:\mathbb{R}\to\mathbb{R}$ satisfying $f'(x)=f(f(x))$. (The answer is: No).    Note: I see that a question of similar type has been asked .


Two days ago, after putting my computer for less than one hour in sleep mode, I noticed weird lines of different colors around all windows as you can see on this screenshot:    Lines are both horizontal and vertical, from different colors, they look like barcodes and on the edges horizontal and vertical lines are scrambled. Those lines appear whether the window is active or not, in the foreground or not.  The lines also appear on the "X" "-" "|_|" icons on the top left hand corner of each window.  The bug also happens in search results in Chrome for instance, actually in any input field with autosuggestion on an HTML webpage:    It also happens when a context menu is open. For instance after a mouse right click there are lines all around the menu.  I use Ubuntu 16.04. I upgraded from Ubuntu 14.04 last week. When I upgraded to Ubuntu 16.04 I had a graphic issue (Computer in low graphics mode, solved with:  ), but after solving the initial issue everything was fine and I don't think I installed anything special after.  If I reboot my computer, the problem is solved. But it reappears after sleep mode.  Specs:   Asus N56VM BIOS: N56VM.206 01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 630M] (rev a1)   Kernel driver in use: nvidia Kernel modules: nvidiafb, nouveau, nvidia_375_drm, nvidia_375  00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)   Kernel driver in use: i915 Kernel modules: i915

After some gorgeous updates I witness this:


I have a few questions, and I was hoping you could help me clear my mind😅   Would you say, “I was watching her dance,” or “I was watching her dancing”?  Would you say, “I was watching you sleep,” or “I was watching you sleeping?” Would you say, ”they were watching them argue, ” ”they were watching them arguing,” or “they watched them argue/arguing”?   And lastly, would you say, ”I’ve never heard you laugh before,” or ”I’ve never heard you laughing before?”    Thank you in advance :)

Meta: I found a very similar post asking the difference between "I saw him cross" and "I saw him crossing". I have three additional questions on sentences of this form.    In , the accepted answer was "I saw him cross the road" implies I saw the entire event of him crossing the road and "I saw him crossing the road" implies I saw him in the middle of the crossing but I didn't wait to see whether he finished crossing the road.   Q1. But what if we watch instead of see? Consider the sentences below.     I watched her dance alone in the room.   I watched her dancing alone in the room.   Watch implies something that goes on for a while. But does the original explanation still hold, i.e. does the first sentence imply I watched the entire dance and the second imply I did not?    Q2. What if you see actions that are almost instantaneous? Does the explanation still hold good? Here is an example:      I saw a flash of lightning strike the pole.   I saw a flash of lightning striking the pole.   Here, we cannot stop seeing in the middle of a lightning since it happens so fast. Does that make the second sentence wrong or can we still use either sentence to mean the same thing?     Q3. Which of the sentences below is/are correct?     I caught her steal the diamond ring   I caught her stealing the diamond ring   When you catch someone in the act, that person could not finish the act. So does that make the first sentence incorrect?


The following problem is from  book     Let $G$ be a finite Abelian group. If $G$ has at most $m$ elements of order dividing $m$ for each divisor of $m$ of $(G:1)$, show that $G$ is cyclic.   I do not understand the notation $(G:1)$. Also I would highly appreciate any hints (need not solve the problem as it coincides with my assignment) for solving the problem.

In Grove's book Algebra, Proposition 3.7 at page 94 is the following     If $G$ is a finite subgroup of the multiplicative group $F^*$ of a field $F$,   then $G$ is cyclic.   He starts the proof by saying "Since $G$ is the direct product of its Sylow subgroups ...". But this is only true if the Sylow subgroups of $G$ are all normal. How do we know this?


Laptop: HP Probook 4520s Windows: Windows 8 x64  This is what I want  I want to install Ubuntu 13.04   When my computer starts, I want it to give me option to choose to load Windows 8 or Ubuntu    As Windows 8 boot loader option (that blue screen, not the Ubuntu screen asking for it) If i dont choose within 15 seconds, windows 8 loads default as automatically Also I want to be able to change the defaults   Can anyone help me and guide me step by step what should I do to install Ubuntu over windows 8 to get what I want  Thanks in advance!  Edit: There are already similar questions, but in this case, Windows is not UEFI, I have installed windows 8 myself, built in windows was Windows 7 in my laptop And I can not understand or find the easy steps to do the above anywhere

I have two partitions on my hard-didk , I have installed ubuntu on my 1st partition and windows 8 later on another partition.Now i can only boot into windows 8 because it doesn't recognize Ubuntu.  How would i dual boot my PC without using grub . I would like using Windows 8 boot manager as its pretty neat.  This is what i have tried :  I tried using easyBCD but it doesn't work.It causes the boot manager to switch to windows 7 Boot Manager .  EasyBCD creates a C:/NST/AutoNeoGrub0.mbr file .  As EasyBCD was causing the boot manager to switch i created a manual entry to the BCD store uisng windows bcdedit command and point it to the C:/NST/AutoNeoGrub0.mbr file created by EasyBCD. This gave me the Windows 8 Boot-Manager with Ubuntu Entry,but grub is unable to find the root partition.  Is there any other work around or solution for this ?  Any help would be appreciated.  Note: The windows 8 boot Manager is sky blue color interactive menu with mouse and other options and windows 7 boot manager is the normal black and white one where you can only use your keyboard  I don't want to install grub because it would prevent my windows 8 from updating as its a genuine MSDN version and various other reasons


I have MS Office 2010 64 bit SP2 (from my university) which I would like to install on Ubuntu 14.04, how do I go about doing that?  I have Wine 1.6 (not sure if there is a specific -bit version I need) as well as PlayOnLinux  Regards

I want to know how to install Microsoft Office (specifically, Microsoft Office 2010) in Ubuntu?   I am a die hard fan of MS Office and I want to know if there is a way I can use it in Ubuntu.


We always assign a voltage drop to a resistor when a current goes through it in a closed circuit. I was wondering if this voltage drop is due to dissipated heat from the resistor or is there another reason?

OK, very basic question here.  I read lots of books, searched quite a bit, and every description I read seemed to talk about the flow of electrons and right away go too deep in theory for me to grasp the basic principle of their use.  I understand a resistor limits the "flow", so that an LED doesn't blow up for example. But I fail to understand exactly what a resistor does to current and voltage...  Do resistors affect both current and voltage? In what manner?


Now I'm using two methods, one as StartCoroutine and one not.  What I want to do is to have just one method and when I set the StartCoroutine variable to true or false when the game is running I want it to switch between the coroutine and the main. Is there a simple way to do it with one method and not two, if not, how do I achieve this?  using System.Collections; using System.Collections.Generic; using UnityEngine;  public class Grid : MonoBehaviour {     public GameObject gridBlock;      public int worldWidth = 10;     public int worldHeight = 10;     public bool StartCoroutine = false;      public float spawnSpeed = 0;      void Start()     {         if (StartCoroutine)         {             StartCoroutine(GenerateGridSC());         }         else         {             GenerateGrid();         }     }      private void GenerateGrid()     {         for (int x = 0; x < worldWidth; x++)         {             for (int z = 0; z < worldHeight; z++)             {                 GameObject block = Instantiate(gridBlock, Vector3.zero, gridBlock.transform.rotation) as GameObject;                 block.transform.parent = transform;                 block.transform.name = "Block";                 block.transform.tag = "Block";                 block.transform.localPosition = new Vector3(x, 0, z);             }         }     }      IEnumerator GenerateGridSC()     {         for (int x = 0; x < worldWidth; x++)         {             yield return new WaitForSeconds(spawnSpeed);              for (int z = 0; z < worldHeight; z++)             {                 yield return new WaitForSeconds(spawnSpeed);                  GameObject block = Instantiate(gridBlock, Vector3.zero, gridBlock.transform.rotation) as GameObject;                 block.transform.parent = transform;                 block.transform.name = "Block";                 block.transform.tag = "Block";                 block.transform.localPosition = new Vector3(x, 0, z);             }         }     } }

I'm generating a level, and I have an optional delay to show the steps level generation one by one.  If my generationDelay boolean is true, I want to use StartCoroutine to spread the generation out over time. If it's false, I want to call the same method but without StartCoroutine.  The problem is that the method is type IEnumerator.  I can make two methods one type of IEnumerator and one not. But I wonder if there is a way to use one method.  In the first script top i did:  public bool generationDelay = false;   Then in a method:  private void BeginGame()     {         mazeInstance = Instantiate(mazePrefab) as Maze;          if (generationDelay == true)         {             StartCoroutine(mazeInstance.Generate(generationDelay));         }         else         {             mazeInstance.Generate(generationDelay);         }     }   Then the other script where the method Generate is: In the top:  public float generationStepDelay = 0.01f;   Then the method Generate:  public IEnumerator Generate (bool generationDelay) {          if (generationDelay == true)             WaitForSeconds delay = new WaitForSeconds(generationStepDelay);         cells = new MazeCell[size.x, size.z];         List<MazeCell> activeCells = new List<MazeCell>();         DoFirstGenerationStep(activeCells);         while (activeCells.Count > 0) {             yield return delay;             DoNextGenerationStep(activeCells);         }     }   I'm getting an error on the line:   WaitForSeconds delay = new WaitForSeconds(generationStepDelay);      "Embedded statement cannot be a declaration or labeled statement"   And an error on the line:  yield return delay;      "The name 'delay' does not exist in the current context"   The reason I want to use a bool variable is that when i'm using StartCoroutine it's kind of slow, even if I change the value of generationStepDelay to 0 it's kind of slow. And if I'm not using StartCoroutine and not using the Generate method as IEnumerator it will work fast.  So i wonder what should I do and how?


How can I find email older than 10 years in Gmail? I need my messages since the beginning; I guess 2003 or 2004. I see only since 2007!

There are similar questions and several answers. I tried to follow the methods provided in the answers.  They did not work. So I am going to ask it again with more specifics.  I only knew the date of the email in the in-box in 2012 and the content of it but did not know the exact wording of the subject. Is it possible to find this email?


I have converted a GIS shapefile of Botswana from the geographic coordinate system GCS_WGS_1984 to the projected coordinate system Africa_Albers_Equal_Area_Conic to be able to calculate the area of the polygons of the shapefile (and later to calculate buffers etc.). But the scale of the projected shapefile is completely wrong, which skews the area (and distance) calculation. For example, when I use the ruler to calculate the distance between two points, a ~113km distance in reality is measured as a 0,001087 km distance on the data frame, thus about 100 000 times too small...   But when I do the same distance measurement with the ruler when the shapefile is under the geographic coordinate system GCS_WGS_1984, there is no problem.   Does someone have an idea how to fix this problem, and end up with a correct scale when I'm using the projected coordinate system?

I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I cannot figure out how to make the other 3 show up at once on top of each other.  Before I opened ArcMap, I used ArcCatalog where I right-clicked 3/4 of the shapefiles and  clicked Properties → Coordinate system → Import and then clicked on my Trees layer, which has the coordinate system I want the other 3 to have. But when I opened ArcMap the 4 layers did not overlap, nor could I move them above or below each other.


We run stand alone instances all virtual. SQL 2012 - SQL 2017 Backups are performed by a third party tool so the server has no need to access anything on the network.   Agent jobs are all run via proxy accounts.   I've started to use virtual service accounts since i don't see the need to setup AD accounts and also Microsoft indicates to use a VSA or MSA (if network access is needed).  I just noticed today that, in my sp_Blitz results, the lowest priority issue indicates AD accounts are preferred.  Now of course it is the lowest priority, which to me is a non issue, but I'd really like to know why there is a preference (at least from Brent) to use AD accounts.

My question is, if you create a new domain user account for each of the SQL Server processes, what permissions should be set for each account? Or does the SQL configuration manager actually take care of this, and I just had an unforeseen issue?  I quite often have to setup Microsoft SQL Server and wondered if anyone can provide advice on configuring the accounts the services should run as. IMO this has been vaguely documented by Microsoft, while they point you in the right direction I have never been able to find any concrete examples.  To summarize what I've seen so far:  For simple deployments\development environments it is OK to use the virtual account defaults the installer uses: e.g. NT SERVICE\MSSQLSERVER  Avoid using the SYSTEM account, this is not secure.  For production and in domain environments it's recommended to use either a Managed Service Account, or create a domain user account (not an admin) for each service. Allegedly if you use a domain account at installation time the installer will set any required permissions for you.  If changing the service account on an existing install from a virtual account to a domain account the recommendation is to use the SQL Server configuration manager to set the new service accounts. Allegedly this will set any required permissions for you.  I just tried changing the service account in an existing install to a domain account and it would give me a logon failure until I granted the account log on as service permission, which contradicts the part where the SQL Server configuration manager will set any required permissions. (Although I'm not sure if a GPO may have interfered with setting this local security policy)  Microsoft does provide a list of the permissions that the SQL Server Setup grants .  But it's not clear to me if that is something I should be doing manually for the user I create to run the service as, or whether using the SQL config manager should automatically set these permissions.  SQL Server 2014, Domain Controller is on Windows Server 2008 R2.


This morning while I was doing a bit of work on my production server, when I accidentally executed the following command: sudo rm -r /*   Sadly, the server no longer accept my public key or password for any user via SSH. And files were hosted on /home directory instead of /var/www is there any way to restore the files? And after this incident happen I took AWS Snapshot of AWS EC2. Then Relaunch it by taking new server. Although I lost the all my files and project. But I discovered that I still have database. As I've also hosted another application under /var/www directory it seems to running fine. Would it possible to recover the mysql database from Secondary Image on server? I tried running executing previous mysql_user and mysql_password on my new server it is not authenticating.

Please note: The answers and comments to this  question contains content from another, similar question that has received a lot of attention from outside media but turned out to be hoax question in some kind of viral marketing scheme. As we don't allow ServerFault to be abused in such a way, the original question has been deleted and the answers merged with this question.      Here's a an entertaining tragedy. This morning I was doing a bit of maintenance on my production server, when I mistakenly executed the following command:  sudo rm -rf --no-preserve-root /mnt/hetznerbackup /  I didn't spot the last space before / and a few seconds later, when warnings was flooding my command line, I realised that I had just hit the self-destruct button. Here's a bit of what burned into my eyes:  rm: cannot remove `/mnt/hetznerbackup': Is a directory rm: cannot remove `/sys/fs/ecryptfs/version': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/inode_readahead_blks': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/mb_max_to_scan': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/delayed_allocation_blocks': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/max_writeback_mb_bump': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/mb_stream_req': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/mb_min_to_scan': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/mb_stats': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/trigger_fs_error': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/session_write_kbytes': Operation not permitted rm: cannot remove `/sys/fs/ext4/md2/lifetime_write_kbytes': Operation not permitted # and so on..   I stopped the task and was relieved when I discovered that the production service was still running. Sadly, the server no longer accept my public key or password for any user via SSH.  How would you move forward from here? I'll swim an ocean of barbed wire to get that SSH-access back.  The server is running Ubuntu-12.04 and hosted at Hetzner.


How can I initialize a structure if one field in the structure is itself a structure?

I want to initialize a struct element, split in declaration and initialization. This is what I have:  typedef struct MY_TYPE {   bool flag;   short int value;   double stuff; } MY_TYPE;  void function(void) {   MY_TYPE a;   ...   a = { true, 15, 0.123 } }   Is this the way to declare and initialize a local variable of MY_TYPE in accordance with C programming language standards (C89, C90, C99, C11, etc.)? Or is there anything better or at least working?  Update I ended up having a static initialization element where I set every subelement according to my needs.


This is rather an intuitive question, in the sense that indeed a real number raised to the power of an irrational doesn't make sense but I wanted to know what does it mean intuitively. If $2^7=2*2*2*2*2*2*2, 2^{\frac{1}{2}}=\frac{1}{\sqrt{2}}$ and $a^b=a*a*a*a*a*...*a\, \,  b$ many times, I'm curious as to what does $2^π$ mean. Obviously it's equal to $8.8249778271...$ but what's the meaning in the aforementioned scenario?

Say I have two numbers, $c\in\Bbb R^+\,,q\in\Bbb{R\setminus Q}$.  Is there a way to approximate the value of $c^q$?  This question bugging me because of how simple it sound in compare to how complicated it is. First I want to understand what a power of irrational number is, when talking about $\Bbb R^+$(I use this domain for sake of simplicity) we have very well defined actions for power a rational number, we can even use some theorems to get $c^{a/b}=\sqrt[b]{c^a}$, but when I am dealing with irrational number I can not do this.  I know that we have some definition for this because the solution of the equation $2^x=3$ is irrational.  So what exactly does it mean to take something to a irrational power and is there a way to approximate a numeric value for this?


Given smooth real-valued function $f: \mathbb{R}\rightarrow\mathbb{R}$ with $f(0) = 0$ and $f(1) = 1$ prove that there exist $x_1, x_2 \in [0, 1], x_1 \ne x_2$ such that  $\frac{1}{f'(x_1)} + \frac{1}{f'(x_2)} = 2$.   The only thing I could think of is noticing that by Lagrange's Mean Value theorem there exists $x'$ with $f'(x') = 1$: $$f(1) - f(0) = f(x')(1 - 0)$$  I can neither prove there exists another point with derivative being equal to $1$ not come up with another solution idea. Could you help me please?

Suppose that $f$ is continous on $[0,1]$ , differentiable on $(0,1)$ , and $f(0)=0$ and  $f(1)=1$.For every integer $n$ show  that there must exist $n$ distinct points $\alpha_1,\alpha_2\cdots,\alpha_n$ in that interval so that    $\sum \limits_{k=1}^n \frac{1}{f'(\alpha_k)} = n $   Is it theorem or i can show it with basic differentiation knowledge .Please give me hint .


Let $ζ_7=e^{i2\pi/7}$ be a 7th root of unity. The field $\Bbb{Q}(ζ_7)$ contains a quadratic subfield that can be expressed in the form of $\Bbb{Q}(\sqrt{D})$ where D is an integer. What is D?  I understand that there is a field extension of order 6 and therefore there will be a quadratic subfield, but how do we find out what D is?

Let $\zeta_7= e^{i2\pi/7}$ be the $7$th root of unity.Find the quadratic sub field of $\mathbb Q(\zeta_7)$ which can be expressed in the form $\mathbb Q(\sqrt D)$,where $D$ is an integer.  My try:let $\omega=\zeta_7+\zeta_7^{-1}\in\mathbb{Q}(\zeta_7)$ is real which is $\omega=2\cos(2\pi/7)$. Thus $K=\Bbb{Q}(\omega)$ is a proper subfield of $\Bbb{Q}(\zeta_7)$. And the polynomial $$ p(x)=(x-\zeta_7)(x-\zeta_7^{-1})=x^2-\omega x+1 $$ has its coefficients in the subfield $K$. Thus it has to be the minimal polynomial of $\zeta_7$, and $[K(\zeta_7):K]=2$.  But the problem is that what is $D?$ and how can i find that?Thank you


I cannot get updates to work.  Here is message  The following packages have unmet dependencies:  libgtk-3-0 : Depends: libwayland-client0 (>= 1.0.2) but it is not installed               Depends: libwayland-cursor0 (>= 1.0.2) but it is not installed   When I run apt get -f it says I do not have permission.  Please help.

Occasionally, when I'm installing stuff, I get an error like the following:  Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  package1 : Depends: package2 (>= 1.8) but 1.7.5-1ubuntu1 is to be installed E: Unable to correct problems, you have held broken packages.   How can I resolve this?


Should users be able to self-migrate a question if they realize that they've posted it on the wrong site? Should there be a reputation threshold before this is enabled?

Currently it is often clear to a user that a question really belongs on another site. This is especially true after a comment to that effect is received on the question by another user. Migration by the user however means:   registering on the other site going back to the original site, editing the question, copying the content creating another question on the other site pasting in the content (which is hopefully still in the clipboard) going back to the other site, cancelling the edit and then deleting the question, hoping that no answer has been given.   This is not very obvious, user friendly or efficient. Besides that, in my experience, people don't like to be asked to delete their questions if you hint to them what they should do.  So I would propose that we let users migrate their own unanswered questions instead. Possibly this requires some safeguard, e.g. a trusted user notifying them about the other site. If the user does not exist on the other site the user could be automatically asked to register for the other site as well so that the other site does not have to deal with unregistered users all the time.


Let $\mathcal{L}=(L;\land,\lor)$ be a lattice. Show that the lattice $(\operatorname{Con}\mathcal{L},\subseteq)$ is distributive.  I understand that I only need to show that for any $a,b \in L$ and congruences $A,B,C$ that $$(a,b ) \in(A\land(B\ \lor C)) \Rightarrow (a,b) \in ((A\land B) \lor (A\land C)).$$  If we take $(a,b) \in (A\land(B\ \lor C))$ then $(a,b) \in A$ and $(a,b) \in (B \lor C)$ and we only need to show that $(a,b) \in   B$ or $(a,b) \in C.$  It should be easy, but for some reason I can't prove this.  Any help would be greatly appreciated.

$\newcommand{\r}[1]{\mathrel{#1}}$ First, a few definitions. Given a lattice $L$, a congruence on $L$ is an equivalence relation $\theta$, compatible with the lattice operations, i.e. if $x_1\r{\theta}x_2$ and $y_1\r{\theta}y_2$, then $x_1\wedge x_2\r{\theta}y_1\wedge y_2$ and $x_1\vee x_2\r{\theta}y_1\vee y_2$. The congruences on $L$ form a lattice, with meet being intersection and join being the equivalence envelope.  I'm trying to prove that this lattice of congruences is distributive. So let's take three congruences $\theta_1,\theta_2,\theta_3$ and attempt to prove that $$\theta_1\cap(\theta_2\vee\theta_3)\subseteq (\theta_1\cap\theta_2)\vee(\theta_1\cap\theta_3)$$  For a start, let's try to prove something easier which should lead me to the general idea. Take elements $x,y,z$ such that $x\r{\theta_1}y,x\r{\theta_2}z$ and $z\r{\theta_3}y$. We want to prove that $x(\r{(\theta_1\cap\theta_2)\vee(\theta_1\cap\theta_3)})y$.   Start with $(x\wedge z)\r{\theta_1}(y\wedge z)$, which gives  $x\r{\theta_1}((y\wedge z)\vee x)$. Similarly, $(x\wedge y)\r{\theta_2}(z\wedge y)$ and $x\r{\theta_2}((y\wedge z)\vee x)$. This gives  $$x\r{(\theta_1\cap\theta_2)}((y\wedge z)\vee x)$$  I expect a similar manipulation should now give $$((y\wedge z)\vee x)\r{\theta_1\cap\theta_3} y$$ but I can't see how to manage this. Is this even in the right direction? I suppose something other than $((y\wedge z)\vee x$ could be the middle link, but nothing obviously better comes to mind.


I need to allow users inside my lan to use BitTorrent clients, but I need to route all BitTorrent (and only BitTorrent) traffic via Bulletproof VPN. In other words, I need to prevent advertising my router's WAN address as a BitTorrent peer address.  Well, I can establish VPN connection on every Windows PC (via Bulletproof VPN) and it seems I can bind every BitTorrent client to the VPN interface using , but how can I instruct Windows to use different gateway for the VPN interface/address? Is there something like PBR in Linux?  Edit: Maybe I'm wrong, but basic routing is the same in Windows and Linux – it is destination-based. All IP packets regardless of source address will be routed to the same gateway. But If I want to send packets to the same destination using different gateways, I need some kind of policy-based routing (in this case – source-based routing)

I have tried ForceBindIP, but it has a significant downside - it doesn't affect the children of the application I'm trying to bind, it only affects the application itself. It also can't force an application to always run through a specified interface, it has to be run through forcebindip.exe every time. It becomes a problem with applications like League of Legends where the process tree looks like that:    The launcher runs the patcher, the patcher run the client, etc. I can only affect the parent of all these processes in the tree, so the actual game is not bound to the interface I want, making this whole venture pointless.  Is there a more modern alternative to ForceBindIP for Windows 7? There are many questions similar to this one on this site, but they are mostly old. Maybe there is now a better way to solve this problem?  My current idea is to do the following:   Set up local 3proxy server bound to the desired interface. Run the game through Proxifier or similar software configured to run through that local proxy.   I'm not sure if that will work, but even if it will, it seems like a sub-optimal solution. Do you guys have any better ideas?  Edit: My idea didn't work :(  Edit 2: Basically, what I'm trying to achieve is bind a few applications to a regular interface, while VPN is running. The reason is that I need to connect through VPN most of the time, but some applications (such as games) don't work properly this way, because of higher ping and other issues.


While working on some field extensions I came across this "proof" that $i = 1$, but I am not sure what is wrong with it:   We know $ i = \sqrt{-1} = (-1)^{1/2}$. Now we have the following equation: $$\begin{align} i \sqrt[4]{-2} =(-1)^{1/2}(-2)^{1/4} &= (-1)^{1/2}(-1)^{1/4}(2)^{1/4}  \\ &= (-1)^{3/4}(2)^{1/4}\\  &= (-1)^{1/4}(2)^{1/4} \\ &= \sqrt[4]{-2} \end{align}$$  Dividing both sides by $\sqrt[4]{-2}$  would yield $i = 1$.

I know there must be something unmathematical in the following but I don't know where it is: \begin{align} \sqrt{-1} &= i \\\\\ \frac1{\sqrt{-1}} &= \frac1i \\\\  \frac{\sqrt1}{\sqrt{-1}} &= \frac1i \\\\  \sqrt{\frac1{-1}} &= \frac1i \\\\  \sqrt{\frac{-1}1} &= \frac1i \\\\  \sqrt{-1} &= \frac1i \\\\  i &= \frac1i \\\\  i^2 &= 1 \\\\  -1 &= 1 \quad !!? \end{align}


I've a polygon layer for parcels in a landscape protection area and a point layer, contains zoological data (e.g species, entities, etc.).  How can I make a statics for each polygon, contains the list of observed species, the count of observations by species and the sum of entities by species?  I would like to make it in QGIS with shapefiles or spatialite database.

I have a polygon shapefile of many lakes, I also have a point shapefile of locations on those lakes where fish were caught.  The point shapefile contains the attributes: Fisherman_iD, Fish_Caught, Lat, Long.  The polygon shapefile contains the attributes Lake_name, Points_per_polygon(PNTCNT)  Each point obviously has differing entries under the fish_caught field.   What I want to get is the average fish caught per lake (polygon).  So I need to have a total number of fish caught, per individual polygon, and then I can divide that by the PNTCNT file I create using the Points in a Polygon tool.  Ideas? I am relatively new to QGIS.


I am trying to show that if $K( \alpha)$ over $K$ is an extension of degree 2, then $ \alpha^2 \in K$ if the characteristic of $K$ is not $2$.  Let's suppose the minimal polynomial of $ \alpha$ is $f(t) = t^2 +bt + c$.  I am able to use the quadratic formula, and I can show that both roots of $f$ are in this extension (i.e. $K (\alpha) = K( \alpha, \beta)$ where $\alpha, \beta$ are the roots of $f$), but I don't see how this helps. The degree of the extension only tells me immediately $1, \alpha, \alpha^2$ are not linearly independent, but that only immediately says they satisfy a quadratic, not that $\alpha \in K$.   How can I proceed?

I am told that $K \leq L$ is a field extension of degree 2 and that $K$ has characteristic not 2. I am then asked to show that $\exists \: \alpha \in L$ such that $L = K(\alpha), \; \alpha^2\in K $  So far I have that:  $\exists \; \alpha_1, \alpha_2 \in L$ such that $L = K( \alpha_1, \alpha_2)$  $\Rightarrow |L:K| = |L:K(\alpha_1)| |K(\alpha):K| $ so $|K(\alpha):K| = 1$ or $2$  $|K(\alpha_1):K| = 2 \Rightarrow L = K(\alpha_1)$ and $deg(f_{\alpha_1}(t)) = 2  $ where $f_{\alpha_1}(t)$ is the minimal polynomial of $\alpha_1$ over $K$   So $f_{\alpha_1}(t) = t^2 + at + b$ for some $a,b \in K$  Also, $|K(\alpha_1):K|=1 \Rightarrow K(\alpha_1) = K$ and $L = K(\alpha_2)$ which means $degf_{\alpha_2}(t) = 2$ where $f_{\alpha_2}(t)$ is the minimal polynomial of $\alpha_2$ over $K$.   So $f_{\alpha_2}(t) = t^2 + at + b$ for some $a,b \in K$  Given that we consider the same polynomial each time, relabel to consider:   $f_{\alpha}(t) = t^2 + at+ b $ for some $a,b \in K$  We have already demonstrated that $L=K(\alpha)$ for some $\alpha \in L$ so now we much show that $\alpha^2 \in K$  $\alpha^2 \in K \Leftrightarrow a = 0_K$  I now have no idea how to show that this coefficient of $f_{\alpha}(t)$ is necessarily $0$.   I know that $f_{\alpha}(t)$ has two roots in $L$ and that because $K$ and thus $L$ has characteristic not 2, they cannot be the same root, but I don't know how to then conclude that they must sum to $0$  Any help would be greatly appreciated.


Is it possible to take a 2D object like this rectangle and extrude it into a half-cylinder? And, could it be done so that a pattern on the former is transferred to the surface of the latter? Not by simply draping the pattern over the half-cylinder, but projecting each point upwards from the plane to the cylinder's surface. Because the height of any point on the curved surface is related to the horizontal distance from the long edge in a predictable manner (Pythagoras' theorem) this feels like it should be a simple process, but I cannot work out a method.

I have a city model (all one mesh) and a separate curved base plane. I would like to have the bottom faces of the each building in the city mesh flat against the plane and keep each building at 90 degrees to follow the curve of the base plane. This is illustrated here in the inception movie poster although this looks more like a sharper curve than I thinking but is a very good visual.    (source: )    I have tried the shrink wrap modifier but cant seem to get the settings to keep each building 90 degrees to the curve. I cant use the particle method because I want to use a real city model that is one mesh.  How can I do the Inception style city on a curved plane effect in blender?


I can get why I am getting downvotes when I ask question about JavaScript - I don't have experience and should learn language instead of doing stuff with it.  I can't get why I am getting upvotes on some not-so-popular exchange sites like neo4j for a similar stupid question. But it lets me not get banned from the Stack Overflow site and keep asking questions.  And I certainly can't get why I am getting downvotes on an iPhone forum when I asked about similarity between a battery in an iPhone and a Tesla car.  I am not going to give links to my question, because I kind of feel I will get even more downvotes and will get banned. The only thing I want to know - how to not get downvotes?

The title of  of  is, "Is it posible [sic]?"  This doesn't provide any information at all. It should be mandatory for everyone asking questions on the Internet to read , which says:     Help your community learn from the question. When you field a good question, ask yourself "How would the relevant documentation or FAQ have to change so that nobody has to answer this again?"


My father was born in Spain and all his family are Spanish from as many generations back as we can find, my mother was born in Ireland and her Irish family history has been traced back to the times of vikings. I was born in New Zealand, and am unsure what my correct 'race' is. I always mark myself down as Caucasian but could it be that I am part Hispanic too?

My sister, cousins, and other relatives speculate that my mom's grandmother was Jewish (for various reasons). I've heard people say at times things like, for example, "I'm 50% German" or "I'm 25% Swedish." This has to do with their ancestry. But, how exactly is this calculated? Say for example that my mother's paternal grandmother was indeed 100% Jewish, what would that make me and my siblings, and how is it calculated?


im having a string like this which im trying to save to my mysql database  $str = "The size id 9” x 12” and some other";   here the ” is not the regular "  Its a part of an Ajax response,In the php side this is what im using  header("Content-Type: text/html; charset=utf-8"); echo $this->_helper->json(array("string is" => $str));   My but console shows 9[a sqaure box] x 12[a square box] //actually a square box cant able to paste it  And im saving this string to my database which has the charset utf8mb4 which is also not correct (ignores the ” in the table while saving)  Can somebody show me which charset i need to use for both showing in html and saving in mysql

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.


Is it necessary to provide bank statements from the last six months when my employer is sending me on a trip and is paying all the costs? If providing it is not a 'must', then is it redundant and negative?  Furthermore, is it sufficient when the employer provides a simple signed letter stating that they are going to cover all expenses? Or should they provide a financial statement of some sort as well? I cannot find anything on this, GOV.UK simply says attach a letter from your employer. But is this truly enough?

The UK Visas and Immigration Directorate publishes  that provides helpful tips that can result in successful visa applications. Section 2 of this guidance opens is entitled "other documents you may want to provide" (emphasis mine).  Section 2: other documents you may want to provide – all visitors This section provides guidance on the types of documents that you may want to provide to help us consider your application against the Immigration Rules. Previous travel documents/passports, which show previous travel. Financial documents showing that you have sufficient funds available.  These must clearly show that you have access to the funds, such as:  bank statements building society book proof of earnings such as a letter from employer confirming employment details (start date of employment, salary, role, company contact details) where a third party (who is either in the UK or will be legally in the UK at the time of your visit) is providing financial support to you e.g. a business, a friend or a relative, documents to show that they have sufficient resources to support you in addition to themselves and any dependant family should be provided   The first item is "bank statements" and this ties in with the , which says...  evidence that you can support yourself during your trip, eg bank statements or payslips from the last 6 months  (Note 'eg' is a Latin abbreviation meaning "for example"; this appears to be optional rather than a fixed requirement.) Question: How should someone interpret this such that the chances of success are maximized? How many statements should I submit? What are they looking for and what do my bank statements tell about me?


I'd like to manipulate the loop behavior using user defined counter variables. I tried passing variables as arguments and also tried hard coding them in script itself but nothing worked.  #!/bin/bash  start_hour=0 #can be passed as argument ($1) end_hour=24 #can be passed as argument ($2)  for i in {$((end_hour))..$((start_hour))} do         echo $i done   Output {24..0}

How do I iterate over a range of numbers in Bash when the range is given by a variable?  I know I can do this (called "sequence expression" in the Bash ):   for i in {1..5}; do echo $i; done   Which gives:     1    2    3    4    5   Yet, how can I replace either of the range endpoints with a variable? This doesn't work:  END=5 for i in {1..$END}; do echo $i; done   Which prints:     {1..5}


From what I can remember, a down and out family of space traders, in which one female member of the family is a psychic or a witch, run into an alien ship, also running out of options.  Possibly the alien ship was alive, could be mistaken about that part.

I am searching for a fascinating story I once read about a member of an social insectoid race. He is sent by his queen to make first contact with the strange humans and serve as liason. He learns to see and understand beyond his race's limits. He tries to warn his queen about the dangers, but before he can deliver the message he gets killed because he is seen as invested/impure and served its purpose.  The humans in the story, a man and a woman are not hostile towards their comrade. They seek their advantage but try to understand their guest. In the end it is humanity's adaptability and competitiveness that is the threat and not any violent behaviour.  As far as I remember it was a paper back from the 80s or the early 90s.


I'm submitting a paper to a CS conference, where I've just got the feedback from my professor. He wants to delete the few lines citing the implementation libraries such as sk-learn as well as more specialized libraries (3 in total). He feels that the lines don't fit in (which I kinda agree with) and that they make it look more like I just "plug n' played" without doing real research. On the other hand, I feel that the authors of these libraries should get some recognition for their hard work.  What is the general feeling towards not citing the libraries used? Would you advise me to discuss this with my professor or just delete the citations?  -- Edit --  It should be noted that the contribution is substantial and I definitely deem it good enough to be published. I just haven't done that much coding of new methods, but instead found interesting insights on important datasets using known methods.

When writing a manuscript for a scientific article, I often wonder what software I should cite or acknowledge, and how.  The first problem is to make a choice which software to cite. On the one hand, there is no way to cite all software, as this would mean to cite my whole software stack (Linux, GNU tools, emacs, git, ...). On the other hand, not citing any software is not fair, either. Furthermore, some software explicitly asks to be cited, some software doesn't. Also, some software is really crucial to the results, some isn't. Another important aspect is that citing software is not only about giving credit to the authors of the software, but also to give other scientists hints on what software they might want to use. So, the choice which software to cite is a problem.  The second problem is how to cite the software. Some (scientific) software does provide a classical scientific article that can be cited. However, in this case, no URL to the software is given. Others do not have an associated article. How do I cite these? I have seen people that cite the manual of a software, others just give the URL. What is the way to go?  Another aspect is where to cite the software. Some software can be cited in the course of the articles text, but when it comes to more fundamental software, other places may be more appropriate.  Are there any good ideas out there on any of these aspects?


If so, is the empty function  from it to any other space  considered a continuous function? I can't really convince myself either way.

We know that, indiscrete topology is the smallest topology. It has $2$ elements (they are the empty set and whole set). Suppose the given set is the empty set, then how can I define a topology on that set? Is it possible?


In SQLServer geometry field, I want to change the coordinates of geometry from one spatial reference system to another spatial reference system (from SRID  to SRID ) by using ST_Transform. But the destination SRID 3011 is not available in sys.spatial_reference_systems table.   How I do this conversion? Is there any other way?

SQL Server takes an SRID when creating spatial data, but is it possible to retrieve with a different SRID translating the coordinates?  For example, let's say I have a bunch of spatial polygons using SRID 4258, but I'd like to use alongside some pre-existing data that has an SRID of 4326 -- are there built in conversions, or do I have to handle this conversion myself?  The SQL-MM method, which PostGIS implements is . How do I do that in SQL Server?


Assuming that no one else has physical access to my computer, assuming that I don't run any unusual services, do I still need a strong password for my Ubuntu user account (it has admin privileges)?   I've heard that any Ubuntu system connected to the Internet needs a strong password because it may somehow affect not only this particular system, but even other machines with Internet access as well (for example, it would be easier to install spambots on a machine with a weak password). Is this true? How exactly does this happen? Do I also need strong passwords on my VirtualBox test systems?  Thank you

I recently decided to change my (very) strong user password to something trivial.  This was mostly to eliminate frustration with typing a long password each time I sudo or whatever.  My question is, is there any reason to have a strong user password? considering that most services which I run on my box do not use PAM for auth:   apache2 - uses .htpasswd for access   sshd - only private keys allowed   transmissiond - uses its own http auth   mpd - uses its own auth   samba - limited to LAN   Physical access to the box is out of the question.


In my locality there is no neutral wire. Our transmission company runs only 3 wires(all line/phase) and no neutral(4th wire) at all. Out of three, one runs to our houses. I know it sounds incorrect, but this is the case, they are saving the expense on neutral wire.  Here we use earth wire(physicaly connected to earth) in place of neutral . Each house has its own earthing/grounding. So our earth is our neutral. No difference at all. Everything works just fine, no problem at all.  I know that two wires with different potential are required to create a potential difference. I also understand that we can run loads between two phases. But in this case there is only one. Here we are running loads between a phase and a wire physicaly connected to earth.  I know that current flows in closed loop(it goes back to the source). But in this case, there is only one wire coming from sub-station and another is just physicaly grounded, how the circuit even completes?  Where is the closed loop?

I'm having trouble understanding why the earth is a viable fault path for electricity brought into my home. Isn't there really high resistance? I mean, it's dirt?   Also, let's say I connect the hot wire coming into my house directly to the ground wire. What is the path that the electricity takes to get back and "complete the circuit?"


I am trying to get the value of two text boxes through GET method. But when i try to print them both. I am not able to do it. The code works perfectly when i do it with single text box.  <?php if(isset($_GET['name']) && isset($_GET['id'])) {  $username = $_GET['name']; $userid = $_GET['id']; echo 'Hi '.$username.'
'; echo "Emp Id is ".$userid; } ?>  <form action="contact-DB.php" method="GET"> Enter Employee Name : <input type = "text" name = "name">
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Enter Employee ID : <input type = "text" name = "id"> <input type = "button" name="submit" value="Submit">

What is the difference between HTML <input type='button' /> and <input type='submit' />?


Let $L_n$ be the $n$ th Lucas number, with $$L_0 = 2, L_1=1, L_{n+1} = L_n + L_{n-1}$$ Is it true that for every even number $n \geq 4$, if the number $L_n - 2$ has a prime divisor $p > 2$, then the number $L_{n+1} - 1$ is also divided by $p$? If not, then is the statement still correct with $n = 2018$? If not, how many number $n$ satisfy that if the number $L_n - 2$ has a prime divisor $p > 2$, then the number $L_{n+1} - 1$ is also divided by $p$?  (Sorry, English is my second language)

Sequence $a_0,a_1,a_2,...$ satisfies that $a_0=2,a_1=1,a_{n+1}=a_n+a_{n-1}$  Prove that if $p$ is a prime divisor of $a_{2k}-2$,then $p$ is also a prime divisor of $a_{2k+1}-1$    If $x_{1,2}={1\pm\sqrt{5}\over 2}$ then $a_k = x_1^k+x_2^k$ and $a_{2k}-2(-1)^k = (x_1^k-x_2^k)^2$.


I am trying to calculate a percentage of a field based off the value of another field. if damage = x then return  the value of field !mrkt_imprv! * y  y = percentage value    my code is below its returning an error in the calculate field   def dam_cal():     if !DAMAGE! == 'Affected':         return !IMPRV_MRKT! * .1     elif !DAMAGE! == 'Minor':         return !IMPRV_MRKT! * .2     elif !DAMAGE! == 'Major':         return !IMPRV_MRKT! * .65     elif !DAMAGE! == 'Destroyed':         return !IMPRV_MARKT! * .85   the error is #000989 (line 2) Parameters are not valid.

I'm trying to used the Python syntax in ArcGIS 10's field calculator and am thoroughly confused. So far the most basic calculations are failing me, and I don't understand why. I'm trying to create a function to just set the values of all cells in a column to be a multiple of the argument that I pass in ( I wanted to try something simple to test it out, as anything more complicated I tried also failed).   However, the error messages are telling me that my syntax is incorrect:    but I can't understand what is incorrect.     As an aside, I'm also horrified at how hard it is to write readable python in the field calculator box as there is no syntax highlighting, or clear indentation. It would be quicker, and easier to write an external Python script to do this calculation, but I want to try to figure out how this new function worked within the program.


Let $S=[0,1)\cup[2,3]$ and $f:S \to \Bbb R$ be a strictly increasing map such that $f(S)$ is connected.Can i say that $f$ must be continuous ? According to me $f$ being monotone so only jump discontinuity and since image is connected so no jump discontinuity and hence continuous. Am i right?

Let $S = [0,1) \cup [2,3]$ and $f\colon S \rightarrow \mathbb R$ be such that $f(S)$ is connected . Which of the following are true:  a) $f$ is discontinuous exactly at one point.  b) $f$ is discontinuous exactly at two points.  c) $f$ is discontinuous at infinite many points.  d) $f$ is continous.  I think $f$ is continuous . We need to show that $\lim_{x \to a^+}f(x) = f(a)$ for any $a \in S$. Since $f(x)$ is increasing, $\lim_{x \to a^+}f(x) \leq f(a)$. Suppose $\lim_{x \to a^+}f(x) < f(a)$. Then there is $l$ such that $\lim_{x \to a^+}f(x) < l <f(a)$, which contradicts connectedness of $f(S)$. Similarly we can show that $\lim_{x \to a^-}f(x) = f(a)$.  I would be thankful if anyone would check my solution and correct me if there are any errors.


I have a VM/Hyper-V for RHEL 7 where I need to install Oracle DB Server (12.1.0.2.0) - Standard Edition (SE2) along with App server, apache, local LDAP and other products for Developer Coding  I want to run the Oracle with as less memory as possible, so that my VM is optimum. How to start a Oracle Server Instance with minumum memory

This is a  about  Related:      I have a question regarding capacity planning. Can the Server Fault community please help with the following:   What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application?


I'm new to this site and am taking on some graphics work that requires a big print out. I have never worked on such a large scale and was wondering if you guys could answer some basic questions for me.  I pretty much want to create something like the image below with a chalkboard and chalk lettering effect. I know how to do this in photoshop, but I don't know if the text and images will be blurry if scaled up?  The dimensions are 5' Wide and 7' Tall. I don't know what print company they are using or what the PPI needs to be.  So my questions are: Am I better of trying to create a similar effect in Adobe Illustrator since it's a vector based program? If not, can you explain how I can set it up in photoshop to be printable at that size?  Thank you very much if you read all this. I hope you can help :)

For wall-sized graphics and large banners (e.g. 3m × 5m), what is an acceptable PPI for print? As I understand it 300 ppi is the typical for 'small' artworks (esp. for clean text resolution). However, for small artworks, the audience usually engages at a much closer distance. Therefore, in the interests of keeping a bitmap file down to a reasonable size, can you get away with a much-reduced PPI for a large format/banner print?


When I insert a USB, macOS system (running High Sierra, Mavericks, Mojave)  restarts or freezes with a panic report:  Panic Report:  panic(cpu 0 caller 0xffffff801e4ba207): "a freed zone element has been modified in zone kalloc.16:  expected 0x3f0011b64302a888 but found 0x3f0011b64302a800, bits changed 0x88, at offset 0 of 16 in element 0xffffff8030ed5ac0,  cookies 0x3f0011b64302a888 0x5352105058b7571" @/BuildRoot/Library/Caches/com.apple.xbs/Sources/xnu/xnu-4570.71.2/osfmk/kern/zalloc.c:1122   What exactly does "a freed zone element has been modified in zone kalloc.16" mean and how we get it resolved?  the kernel is getting panic when I am using a third party kernel extension to which I have modified and that deals with USB control. could you please suggest me any of debugging method of kext too.


Why is the hat feature missing sometimes? Actually, It disappeared right now. Could someone tell me what's going on here? Maybe a bug?

The  page indicates "the hats get put back in their boxes on January 4th". Aside from the pure terror that sentence seems to invoke, I was curious of exactly when this is going to be.  I know that the hats have caused a bit of a time warp at times (for example the starred chat hats). Will this be true of the removal process as well?  Do we get our hats until 23:39 UTC Jan 4th, are they removed at the end of UTC Jan 3rd?


My fluid simulation baked and showed up, but when I rendered it it shoed no simulation. The rendered viewport even shows the fluid! The bottom part of the screen shows the rendered viewport, the top screen shows the images after rendered

I have a model of a building with a sidewalk around it.  Both show up when I switch to rendering mode in both Blender Render and Cycles Render mode.  But:  when I hit F12 for a final proper render, the building shows up -- but the sidewalk doesn't.    I've checked the normals and I thought the normals seemed pointed in the right direction.  I've set the Clipping on the Camera to a high number.  I removed all the materials from the sidewalk and added a new material-- the problem persists.  I've exported the blend as an FBX file and the Sidewalk shows up fine in Unity.  Just in final renders, it doesn't show up.    Here is a blend file: .  I tried to destroy everything unrelated to the issue and label things in a clear way.    Thanks.


If we find probability of getting a number, say 800, from the set of infinite then the probability would be 1/infinite which is 0, but there are some possibilities to get 800. How!? Where am I wrong?

Is it possible to pick a random natural number? How about a random real number? Is the axiom of choice involved in this?


How do you know attributes vs methods in Python object?  When using the dir method it only list everything for example dir('string').

dir(re.compile(pattern))    does not return pattern as one of the lists's elements. Namely it returns:  ['__copy__', '__deepcopy__', 'findall', 'finditer', 'match', 'scanner', 'search', 'split', 'sub', 'subn']   According to the manual, it is supposed to contain      the object's attributes' names, the   names of its class's attributes, and   recursively of the attributes of its   class's base classes.   It says also that     The list is not necessarily complete.   Is there a way to get the complete list? I always assumed that dir returns a complete list but apparently it does not...  Also: is there a way to list only attributes? Or only methods?  Edit: this is actually a bug in python -> supposedly it is fixed in the 3.0 branch (and perhaps also in 2.6)


Total Noob here. I've only discovered Linux to get Minecraft working on our Chromebook for my son. I know I need to learn more but really could use some step by step help here.   I am able to run Minecraft by clicking through the files, opening the program in the terminal and typing "java -jar Minecraft.jar" which works fine-- but this is for my 7 year old son so I'd like a little easier alternative.   I've tried creating an icon for running the Minecraft jar file on Xfce through "Creating a Launcher" but it does not work. I've tried various combinations of commands but some will not run at all and others will say it cannot find the file.   What exactly do i need to put in as the command and do i need to put anything in the "Working directory" box?  P.S. I apologize for the low quality pic, but I'm running two different machines right now with multiple windows and didn't feel like worrying about a regular screenshot through Linux.

I use this command in the terminal to run the minecraft launcher with java 8:  /home/max/Java/jre1.8.0_25/bin/java -jar Minecraft.jar   I included the full java path because I installed it on /home as a normal user and i want to include it.   That command works, it opens the launcher with Java 8 but I want to make a bash file so I don't have to open the terminal. And, most important, I don't want the terminal to remain open when I click play in the Minecraft launcher and the game starts.  Now if i close manually the terminal when the game have started, the game is closed too.


I read a comment I found problematic.  I clicked on the little flag, chose the bottom-most radio button in the list of reasons for flagging, and wrote a short text in the input box.  I submitted the flag but no acknowledgment message appeared.  Should one have appeared?  Is there any way for me to verify that my flag actually went out?  Is there any way for me to find out later what the outcome of the flag was?  Is there any way for me to read what I wrote?  What about flags on my own posts?  Is there any info about these that I can see?  I have tried looking at the various similar questions that were suggested by the software, but none of them are recent, and I suspect that the answers that I found through this approach are obsolete.

I would like to see a "my pending flags" page/section developed.   At the minute we can flag questions etc and suggest what is wrong with them but there is no way of knowing whether the flags we have placed have been accepted/rejected. We therefore cannot tell (without looking at flag weight that is, at best, guesswork as to which flag was a + and which was a -) which flags were accepted or rejected  This may page may also allow the user to "unflag" accidentally flagged questions or questions that have been revised.  I think such a page would greatly increase the flagging efficiency of both myself and other users.


Overall goal: make a couple USB phone & tablet charging ports from a 12V deep cycle battery.   Steps taken so far: I've read that using a resistor based system to step down from 12V to 5V leads to a lot of heat inefficiency so I purchased a SMAKN 12V to 5V 3A voltage regulator. I can simply solder the + & - terminals of a female USB port to this regulator but I thought it would be more efficient to split the 5V 3A output into 5V 1A and 5V 2A to charge a phone AND tablet at their desired wattages.   Confused part: Googling this leads to surprisingly few results, most of which discuss using PSUs where the answers generally revolve around picking a more specific PSU.. [Edit]: While other answers do discuss the underlying solution, they are specific to choosing a PSU and don't get into the details of how to construct a multi-device USB charging circuit.   Using Ohm & Kirchoff's laws, if I build a parallel circuit with a 5 ohm and a 2.5 ohm resistor, this will give me my 1A (5V / 5 ohm = 1A) and my 2.5A (5V / 2.5 ohm = 2 A).          – Schematic created using   Jump back on google to find a 5 ohm and 2.5 ohm resistor and...I see a number of results some of which say to operate at 1/4 Watt which is clearly way too low.    I called local electronic shops - they all seemed surprised that I needed such a low resistance resistor with such high wattage.  All of which adds up to me thinking I'm going about this incorrectly or am violating some basic principle? Are my resistors (R1 = 5 ohm, R2 = 2.5 ohm) correct? Are there such resistors for 5V circuits? Is this design going to lead to power loss if only of the two USB ports are in use?

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


I would like to know how can we solve the equation $\cos x = x$, without graphing. I know that  there would only be one solution, that is obvious, that too in between $0$  and $\frac{\pi}{2}$. Is there any real expression in finite terms [perhaps we call that closed form, I am not sure] that could give $x$ or $\cos x$. Although I have not studied Taylor series, I know that it only gives an infinite series, which is not what I want. I suspect that it could not be done, but can anyone explain me why?  Just for completeness, Wolfram Alpha, gives the approximate answer $x = 0.7390851332151606416553120876738734040134$, but fails to give a exact solution.

There is an unique solution with $x$ being approximately $0.739085$. But is there also a closed form solution?


The Hell Fire ring does not have a level requirement. It also has a chance to roll Main stat.  Will there be any difference between making it with a level 1 monk, as opposed to a level 70 monk. Will the stats be the same? Meaning will they roll at their level 70 equivelant, as a higher stat?

I've been collecting set and legendary Blacksmith plans as I level my characters, and I teach each of them to Haedrig as I find them. Recently, though, I've started to notice that only a few of these plans are used to make level 70 items, so I'm hesitant to keep collecting them unless I'm playing on a maxed character.  What I want to know is whether or not the level of my character at the time I obtain the plans will affect the level of the item(s) crafted from those plans. (If there are any differences in this regard between legendary and set plans, details would be appreciated.)  If character level does have some effect on what level the crafted item will be, is it possible to get another version of the plan later for a higher-level version of the same item, or am I stuck with the low-level version?


I have downloaded SQLite Studio .bin file. After I made it executable and start it, icon is pretty disappointing. Because of that, I got another .png icon from the web. Changing icon in properties of .bin file works, but only temporary, when app is started, there's still same ugly icon in Unity and ALT+TAB window. Even creating Application Entry in ./local/share/applications/sqlitestudio.desktop with icon path to /opt/sqlitestudio/icon.png doesn't work... I find it in Unity search, icon is good there, but again, after starting application, same old ico. What can I do?  It's Ubuntu 12.04 LTS.  Thanks

When launching java programs (like IntelliJ IDEA and Crashplan) in Natty's Unity launcher, duplicate icons are shown (see image).  For IntelliJ I created the .desktop file, for Crashplan the .desktop file is supplied with the application.  Is there something that can be changed in the .desktop files (or somewhere else) that can prevent this from occurring?  I couldn't find a bug report for unity itself but programs like Gnome-Do/Docky have   and had to make internal changes to their applications to prevent this.   In this image the 1st icon is the one created from the .desktop file and the second icon is after launching it.  Second icon disappears when closing the application.  Custom IntelliJ .desktop file  #!/usr/bin/env xdg-open [Desktop Entry] Version=1.0 Type=Application Terminal=false Icon[en_US]=/opt/idea/bin/idea128.png Name[en_US]=IntelliJ IDEA Exec=/opt/idea/bin/idea.sh Name=IntelliJ IDEA Icon=/opt/idea/bin/idea128.png StartupNotify=true   Crashplan provide .desktop file  [Desktop Entry] Version=1.0 Encoding=UTF-8 Name=CrashPlan Categories=; Comment=CrashPlan Desktop UI Comment[en_CA]=CrashPlan Desktop UI Exec=/usr/local/crashplan/bin/CrashPlanDesktop Icon=/usr/local/crashplan/skin/icon_app_64x64.png Hidden=false Terminal=false Type=Application GenericName[en_CA]=


I got a strange icon I've never seen before on my Samsung A3. It's in the top left corner, shaped like an 'o' letter, but with the top right quarter of the circle broken. Its not a sync icon (that has arrows and it's broken in two halves). Does anybody know what it means? I could not find it anywhere on the web. In the notification swipe screen there is nothing that points at its meaning.  See answer

After I recently updated my phone about a day ago, this strange sign showed up on the top left that I have never seen before. Does anyone know what it means? Or how to get rid of it?


The real numbers $\alpha,\beta$ satisfy $$\alpha^3-3\alpha^2+5\alpha-17=0\tag{1}$$ $$\beta^3-3\beta^2+5\beta+11=0\tag{2}$$ Find $\alpha+\beta$  Are the three roots of both cubic equations unique, or is there only one root? How can you prove it? What's the best approach to this problem?  I tried using Vieta's formulas, where the sum of three roots of (1) and (2) are: $$\alpha_1+\alpha_2+\alpha_3=3$$ $$\beta_1+\beta_2+\beta_3=3$$ Summing both, $$\alpha_1+\alpha_2+\alpha_3+\beta_1+\beta_2+\beta_3=6$$ Assuming there is only one root for each of (1) and (2), we are done, but what if there isn't?

The curve $y = x^3 - 3x^2 + 5x $ is a strictly increasing curve. $y=x^3 - 3x^2 + 5x -17 =0 $ intersect x axis between 3 and 4. $y=x^3 - 3x^2 + 5x +11 =0 $ intersect x axis between -2 and -1. The answer is given 2. Is it possible find exact value  of $\alpha+\beta$


I am trying to send a date value from my java program into an oracle sql database. But I keep getting the error: java.text.parseexception: unparseable date.  I set the date format as:  SimpleDateFormat df = new SimpleDateFormat("yyyy/MM/dd", Locale.ENGLISH);         java.sql.Date date = (java.sql.Date)df.parse(dob_text.getText());   I have set my database with the same date format. And try to send the date through a prepared statement like so:  ps.setDate(3, date);    I am entering a date 1994-09-09. That's the correct date format for the one I declared right? Is there something wrong with my java formation code? Has anyone else had this problem? Any help would be much appreciated

I am trying to use a  as input and then creating a query with it - so I need a .    I was surprised to find that it couldn't do the conversion implicitly or explicitly - but I don't even know how I would do this, as the Java API is still fairly new to me.


What drives this happen? Would it be the internal energy or by an external force? I did try to Google the answer, but could not find a good one.

The origin of spin is some what a puzzle to me, everything spin from galaxies to planets to weather to electrons.  Where has all the angular momentum come from? Why is it so natural?  I was also thinking do photons spin? we always think of the wave as a standard 2d sin wave but could this rotate in 3d? What implications would this have?   And what about spacetime how does all the spinning effect?  This has always been avoided in all lectures and classes I ever went to.


I did create a custom page template and assigned to a page.  I have this code inside:  $news_filter = array(      'category'        => '53',      'posts_per_page'  => 5, );  $news = get_posts( $news_filter );  echo count ( $news );  foreach ( $news as $post ) :  setup_postdata( $post );     the_post_thumbnail();    the_title();    the_content();    endforeach;   It works, but I would learn more and more wordpress so, I would ask, if is there is a way to avoid having to run two queries? For example, I know existing of (custom) filter. Instead to make the loop twice (by WP and by me), can we add a filter, block WP and perform a custom loop?

I'm trying to get my news page to display content from one category only (number 3) but I cant seem to get it to work. Instead of just displaying posts from category 3 it displays posts from all category's.  Here is my code:  <?php get_header(); ?>

Latest News
                              <?php $args = array(                             'post_type' => 'post' ,                             'orderby' => 'date' ,                             'order' => 'DESC' ,                             'posts_per_page' => 6,                             'category'         => '3',                             'paged' => get_query_var('paged'),                             'post_parent' => $parent                        ); ?>                        <?php query_posts($args); ?>                            <?php if ( have_posts() ) : ?>                             <?php while ( have_posts() ) : the_post(); ?>

                                     <a href="<?php the_permalink() ?>"><?php the_post_thumbnail(); ?>                                      <a href="<?php the_permalink() ?>">
<?php the_title(); ?>
                                     <?php the_excerpt(); ?>
<a href="<?php the_permalink() ?>" class="readmore_news">Read more

                              <?php endwhile; ?>                         <?php endif; ?>

  <?php get_footer(); ?>


Let $p$ be an odd prime, $a\in\mathbb{Z}$. Try to prove $$\sum_{y=0}^{p-1}\Big(\frac{y^2+a}{p}\Big)\equiv-1\pmod{p}\tag{1}$$ I find that when $p|a$ it obviously holds, since $$\sum_{y=0}^{p-1}\Big(\frac{y^2}{p}\Big)=p-1$$ Then for $p\!\!\!\not|a$ case, I checked many examples and I guess the LHS may exacatlly equal to $-1$. Then I make it equivalent to consider giving a proof for the following $$\Big(\frac{a}{p}\Big)+2\sum_{y=1}^{\frac{p-1}{2}}\Big(\frac{y^2+a}{p}\Big)=-1\tag{2}$$ which means that we add a same number to modular $p$'s all quadratic residue. I'm really not sure about my guess $(2)$, does the quadratic residue have such translation-like property? And I do not know how to prove $(1)$, can you give me some ideas?

How to calculate such sums as $\sum_{x\in\mathbb{F}_p} \left(\frac{x^2+ax+b}{p} \right)$  If $x^2+ax+b$has a root, $b$ may be eliminated and the sum is evaluated to be $0+\sum_{x\in\mathbb{F}_p^*} \left(\frac{1+ax^{-1}}{p} \right)=-1$. Otherwise to linearize it, you need to go into quadratic extensions. So I guess there may be a solution resorting to extensions of $\mathbb{F}_p$.  It is easy to extend the symbol since the extension is cyclic. But then I need to sum in an unfamiliar space. Can we fix this and eventually give a proof in this flavor?  Any reference is welcome.


What is the rule in use here that allows me to use I do in place of me in the second sentence?    An Olympic sprinter on a bad day runs faster than me on a good day. An Olympic sprinter on a bad day runs faster than I do on a good day.

Consider the sentence "I can run faster than 15 miles per hour." Its meaning is clear and to my eyes obviously grammatically correct. Now let me present some variations that have given me trouble for a long time.  I am faster than 15 miles per hour. – To me this is clearly incorrect. Directly comparing me to a speed doesn't seem right. We need to compare my speed to a speed, or me to another person.  I can run faster than him. – Compared to the base sentence, there is a distinct shift in meaning of the comparison. While before I named a speed faster than which I can run, now I am naming a person. It doesn't seem quite right. I realize the parts of speech can change, but my initial objection is that "him" is not a speed.  I can run faster than he. – This seems most correct to me, but still somehow feels objectionable. Is this in fact the correct way to say it? And if so, is it proper as is or need I say "... faster than he can" or even "... faster than he can run?"  I am faster than him. – With "am" instead of "can run" it now seems slightly more correct. But is it?  I am faster than he. – I'm in doubt here. It doesn't seem wrong to me to say, "I am faster than he is" or even "I am faster than he is fast." (Though I suppose that is a given since I could hardly properly compare to some other category as in "I am faster than he is smart.")  My speed is faster than his. – Hmm. This seems more proper as "my speed is greater than his."   So which of these constructions is correct and which is incorrect? Is there a general rule that I can follow? UPDATE The scholarly article  may be of great interest to some readers!  Once we accept that the elided constituent and its antecedent can differ in form, it becomes reasonable to ask how large this difference can be. The answer in Rooth (1992), Fiengo and May (1994), Chung et al. (1995) and subsequent work is that the wiggle room is actually quite small: the elided constituent and its antecedent are allowed to differ only in the realization of inﬂectional morphology. Other than that, both constituents have to be syntactically and lexically isomorphic.


I'm new to salesforce and I have to parse  JSON and store the values in variables. I have used json2apex which generated 2 classes for me. When I use system.debug I can see it's reading the JSON object, however I have no idea how to store this many variables it in List<> format I used this line to store them but it does not work: for(Meals m: retrievedMeals){ mealData.add(m.meals[]); } Can somebody please give me help me to store these values? public class Meals { @AuraEnabled public List<Meals> meals;  @AuraEnabled public String idMeal; @AuraEnabled public String strMeal; @AuraEnabled public String strCategory; @AuraEnabled public String strArea; @AuraEnabled public String strInstructions; @AuraEnabled public String strMealThumb;  public static Meals parse(String json) { return (Meals) System.JSON.deserialize(json, Meals.class);     } }   public with sharing class MealsRetriever { private static final String MEAL_URL = 'https://www.themealdb.com/api/json/v1/1/search.php?s='; private static final String GET = 'GET';  public static List<Meals> getMealData(){      List<Meals> mealData = new List<Meals>();      Http httpCallout = new Http();     HttpRequest req = new HttpRequest();     req.setEndpoint(MEAL_URL);     req.setMethod(GET);      HttpResponse mealResponse = httpCallout.send(req);     Meals mealParseResponse = Meals.parse(mealResponse.getBody());     List<Meals> retrievedMeals = mealParseResponse.meals;          /*this is the part where i try to store the values, but I dont know how     for(Meals m: retrievedMeals){        //Meals.idMeals = retrievedMeals.get('idMeal');     }       return mealData;     } }

This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, navigate to the  tag.  This question and answer is owned by the community! If you can improve it and make it more useful, you're welcome to edit it.  I have a specific JSON structure in mind. I need to either deserialize this structure that's coming in from a web service, or I need to serialize data into this structure to transmit it to another system. How should I get started on this project in Apex?


I am using an Android smartphone. I wanted to know if there is a mobile application through which we can use chat?

Being able to join chat rooms from the Android app would be a plus! It would truly make us connected on the go, instead of having to sit down at our desks and open a browser window. This will allow more users to fully utilize the chat system and join events no matter where they are.


I want to install Matlab 2018 in Linux. I tried running the following commands:  $ sudo mkdir -p /mnt/cdrom $ sudo mount MatlabR2018b_LinuxX64_DVD1_downloader.ga.iso /mnt/cdrom -o loop   But I was faced with this error:  mount: /mnt/cdrom: failed to setup loop device for MatlabR2018b_LinuxX64_DVD1_downloader.ga.iso.   I have already read and tried what is proposed in this thread but it didn't work:   How can I fix this?

sudo mkdir -p /media/cdrom cd ~ sudo mount -o loop ubuntu-* / mount: ubuntu-*: failed to setup loop device: No such file or directory


I am looking for a short story and anthology / anthologies containing it: A multi generation ship has landed on a planet with very hostile inhabitants on it. The aliens are chipping away at the hull of the ship with primitive instruments.   The leaders of the space ship decide to breed aggressive children to counter the aliens. They know that this is suicidal as the children will be so aggressive that they will kill the parental generation.   I think I read this in an anthology in early 80's / late 70's. Most likely published in 70's.

I believe the main protagonist’s name is Falconer. A human spaceship crashlands on a planet where  conditions are inimical to human life - including a hostile sentient native species. So the humans build a large enclosure for themselves and undergo induced mutations so each succeeding generation is better adjusted to conditions on the planet than the last until finally the last generation is ready to step out of the enclosure.


I'm looking to buy a Inspiron 5491 with i7, 8GB, 2 in 1 configuration. I'm currently using my old MacBook Pro (2012) and switching to Ubuntu. So my plan is to wipe Windows 10 and go full Ubuntu Focal Fossa. I have read problems with the Inspiron 5491 like no audio and WiFi problems witch probably will be fixed on a full install. My concern is that I pay 1000 euros and end op with a laptop that doesn't have a functional audio jack. I asked Dell if I can return the laptop within their returnpolicy (14 days) if I install Ubuntu alongside or on an external disk. I asked 2 times (diffrent employees) and both times they said no. Not sure what to do now. I searched all the internet for the last couple of weeks and can't find anything with the newest Ubuntu.  My main question is: will Ubuntu 20.04 work properly (minor tweaks are fine) on the Inspiron 5491  If there are some alternative 2 in 1 options, pleas let me know. I need an Ubuntu laptop with    at least 2 usb A ports (not trough a c hub) SD-card reader HDMI and DP (trough a c hub is fine, need docking with 2 screens attached) a 14 or 15 inch screen a keyboard with no num-pad so the track-pad will be in the middle 10th gen i7 2 in 1 convertible Upgradable memory to at least 16gb but 32 would be nice Intel integrated graphics is fine, an nvidia battery friendly is okay too   Yes, I know there are special Ubuntu,Manjaro,System76 laptop options, and I know my list is pretty long, but I think I found my laptop with the Dell Inspiron 5000 2 in 1 series  PS: new to this forum, hope I'm doing okay and thanks in advance

I have a similar laptop to    But I am opening another question as the problem I face is different. The  and did not find any experience with the Ubuntu installation.  After switching from RAID to AHCI, disabling a secure boot, updating the BIOS, and play around with the BIOS option, I am trying to install Ubuntu 18.04.03.  I am not actually installing it but just using "Try Ubuntu". I pass to the bootloader the options nomodeset intel_idle.max_state=1 without which the installation stops very early. I've also played around with ipv6.disable.  Everything stops while turning on services(see attached figure). In particular acpid.service is the last thing I see, then the system freezes.  I suspect it is related to ACPI setup but don't have any clue on how to fix it. Any suggestion is much appreciated.


tl;dr: What is the hidden setting that tells the first-time-user-wizard to run? i just want to re-enable that flag so next time the phone boots it shows the new user wizard and UI hints.  A friend gave me his new nexus to install CM11 and a few applications.  To install those applications i created a bogus Google account, downloaded them from the store, configured and then removed my account.  now i want to give the phone back in a way that when it is powered on, it shows the create new account/enable Wifi/etc wizard.  I already tried wiping out data from "one time setup" system application, but that did nothing. Any other ideas?

I am looking for a way to use ADB to trigger Setup Wizard at next boot. I know I can run the following command and get it to pop up. However, I can't figure out what triggers it to start at boot.  adb shell am start -a android.intent.action.MAIN -n com.google.android.setupwizard/.SetupWizardTestActivity   The phone I am currently using is stock and I would like to keep it that way.   I've read the  question:


I was asked this in an interview. You have two features, $x_1$ and $x_2$. You fit a simple linear model on each feature, so  $$ \underbrace{y = x_1 \beta}_{\text{model 1}}, \qquad \underbrace{y = x_2 \beta}_{\text{model 2}}. $$  You compute the $R^2$ value for each model and find that each one has an $R^2$ of $0.1$. Now you fit a model on both features  $$ y = x_1 \beta_1 + x_2 \beta_2. $$  What range of values can you expect this model's $R^2$ to take? I was stumped and am curious how to reason through this.

A very basic question concerning the $R^2$ of OLS regressions   run OLS regression y ~ x1, we have an $R^2$, say 0.3 run OLS regression y ~ x2, we have another $R^2$, say 0.4 now we run a regression y ~ x1 + x2, what value can this regression's R squared be?   I think it's clear the $R^2$ for the multiple regression should be no less than 0.4, but is it possible for it to be more than 0.7?


I'm quite new with Illustrator and I have an issue that I'm trying to find a soluting for a few hours now!  So when I use dark colors on any shape a white thin line appears around it. I tried adding a stroke but the white line moves around the stroke. This is only happening when I'm using dark colors, the lighter colors look as they should! I tried to export as a .png & .pdf and the lines are still visible.  Without a stroke:    With a stroke:    Random light colors:    (Edit) I didn't convert any image to make my design.I drew it right from the start. I tried it again without using divide on my shapes, it still looks the same. I tried to add Offset paths,nothing changed.Even if I add a background the lines are still showing!  English is not my first language, I hope I was understood!

I converted a raster image to vector in Illustrator CS6 using Image Trace then the Expand option, though when I save as an svg the image looks embossed. I suspect it's due to the layer background being white and the paths not lining up, but I'm unsure how to fix it or prove that theory without manually having to adjust every path.   This is how it looks in Illustrator before I export it:    The image looks like this when saved/exported with art optimized option:


for some reason my accountsd is taking so much memory. even though I have a 16 mb macbook pro.. If I kill that process it keeps on opening back up again.. ideas?

Why are the accountsd and securityd processes using so much CPU on OS X 10.10.3? I am on a Early 2011 Macbook Pro.  What are these processes for? Is it safe to kill them? The machine has only been up 4 hours so has been rebooted recently.


My android phone has weak buttons, so I don't use them frequently. I even change my volume from the settings!  But to take a screenshot, I need to press the volume down button and the power button. I have a Motorola Moto E4 Plus running Android 7.1.1.  Is there any other way to take screenshots? I don't want to root my phone.  NOTE: This question is not a duplicate as this is asking specifically without buttons and so helps those who can not use their physical buttons.

Is there a way to take a screenshot of an Android device and save it as an image file?


i want to know do i have to attach a flight booking confirmation with my uk visit visa application? Is there any rules that can reject my visa if i wont attach flight reservation before getting my visa?

Am compiling documents for my visa application and I read that I need to present go and return flight tickets to prove that I will return at the end of my visit. Then a while ago I got to know that I can just get a flight reservation with out buying the flight tickets because the visa application can be refused and you have already bought the tickets.  So l request to know which of the two , having a flight ticket or flight reservation is more compelling to the visa officer and more convenient me because I would buy a flight ticket and my application is refused


In the below XPath, the index [1] is changing every time. Can we handle this?  //button[contains(text(),'Action')][1]   HTML:  <button aria-expanded="false" aria-haspopup="true" class="dropdown-toggle component--button btn--reset" data-toggle="dropdown" type="button"> <span aria-hidden="true" class="icon component--icon icon-angle-down"> </span> Action</button>

How to Handle Dynamic Changing IDs In XPath? for example :   //div[@id='post-body-3647323225296998740']/div[1]/form[1]/input[1]   In this xpath id "3647323225296998740" is changing every time when reloading the page.   Is there any way to handle this type of situation in Selenium?


I am trying to read into a file, make it into an array and print it.  I'm not sure what I'm doing wrong with this code. I've been trying to get a solution but all the solutions I can find are more advanced than what we should be using...I wrote a previous program using the same method but as a Double array. I can't seem to make it work for a String?  I keep getting [Ljava.lang.String;@3d4eac6 when I run it.  I just want it to print boysNames. boyNames.txt is just a list of 200 names in a text file.  Someone please help me, or let me know if this is possible?  this is my code so far  public static void main(String[] args) throws FileNotFoundException {        String[] boyNames = loadArray("boyNames.txt");     System.out.println(boyNames); }  public static String[] loadArray(String filename) throws FileNotFoundException{     //create new array     Scanner inputFile = new Scanner(new File (filename));     int count = 0;     //read from input file (open file)     while (inputFile.hasNextLine()) {         inputFile.nextLine();         count++;     }     //close the file     inputFile.close();      String[] array = new String[count];     //reopen the file for input     inputFile = new Scanner(new File (filename));     for (int i = 0; i < count; i++){         array[i] = inputFile.nextLine();                 }     //close the file again     inputFile.close();     return array; }   `

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the  of the array, as defined by Object.toString():  int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray);     // prints something like '[I@3343c8b3'   But usually, we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs:  // Array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5]  // Array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob]