The expression portfolio career meaning: the fact of having several part-time jobs at once, rather than one full-time job: •   A portfolio career is suitable for people who want to have a variety in their work life. (Cambridge Dictionary) Can anyone tell me when and where it was first used?


Can I roll a Steam game back to a previous version?

The new No Man's Sky update (PC) has rendered my game practically unplayable with how often it crashes. Is there a way to roll it back to the previous version on Steam, at least until they fix the bugs?  (The question "" seems to be specific to a particular game from one particular developer, in beta, and the solutions do not appear to apply.)


I'm having some trouble with the following proof: $$\sum^k_{a=0} {{n}\choose{a}}{{m}\choose{k-a}} = {{n+m}\choose{k}}$$  I'm trying to prove this to learn a couple of things about the Pascal's triangle. I don't know where to start on the proof. I have tried expanding both sides using the binomial coefficient property but have had no luck.


How can I enable my button when 'email' field is valid?

I did this function so that the form button enables when the inputs are different from empty, but I don't know how to do so that in the #email ID the input, in addition to being different from empty, must necessarily contain the character '"@" or the strings "@ gmail.com", "@ hotmail.com". This is the function $(function () { $('#button').attr('disabled', true); $('#textarea, #email, #name').change(function () {     if ($('#name').val() != '' && $('#email').val() != '' && $('#textarea').val() != '') {         $('#button').attr('disabled', false);     } else {         $('#button').attr('disabled', true);     } });  }); This is the HTML <form id="contact-form" method="POST" action="forms/contact-form-handler.php">                 *<input name="name" id="name" type="text" class="form-control" placeholder="Nombre" required>
                 *<input name="email" id="email" type="email" class="form-control" placeholder="Dirección de correo electrónico" required>
                 *<textarea style="resize: none;" id="textarea" name="message" class="form-control" placeholder="Mensaje" row="4" required></textarea>                     Las celdas marcadas con * son obligatorias.

                 <button type="submit" id="button" disabled="disabled"></button>
               </form>


Why are there humans in the Star Wars Universe?

Kind of brought to my attention by .  The poster mentions non-humans, which implies that there are humans in the Star Wars universe.  However, since it happened "A long time ago, in a galaxy far far away", how could there be any humans in the Star Wars universe?  Are there "humans" in Star Wars there just because it was easier to make the movies that way?  Other shows such as Star Trek are about the future of humans, so it's easy to understand the existence of humans in those storylines.  However for Star Wars it just doesn't make sense.  It also seems odd that they'd go around creating all these different species and then just leave the main characters as humans. I guess another possibility is that the humans in star Wars eventually populated Earth, but then what happened to all the technology?


Are there any counter arguments to the claim God does not exist because there is evil in the world?

It's been argued that God doesn't exist because there is so much evil in the world.  For example, suppose a person is violently murdered - an innocent child say.  They argue, God could have prevented that but He didn't, therefore He does not exist.  Are there any good counter arguments to this position?


Warn new users to edit important information into the question upon their first attempt to comment on a question of theirs

Especially on technical sites, as even sporadic users will have noticed, new users very often don't include important information into the question they're posting.  This usually leads the first user passing by to leave a comment asking for clarifications, which punctually get posted in the comments section.  Many times there's not even the need for a user to ask OP to do so, OP just does that because they forgot something or because they want to improve their question by adding more details.  In any case this leads to:   Important information posted into the comments section, where they shouldn't stay; Question not bumping up in the active questions tab, which doesn't help fixing point #1; Unless OP pings one of the users that left a comment in doing so, none of the user who commented will get to know that the requested clarifications were posted, which doesn't help fixing point #1 either.   I think it would be convenient to prompt new users with a popup similar to the popup prompting to leave an explanation upon downvote when a new user leaves a comment under the following conditions:   OP hasn't been prompted before (i.e. do this only upon OP's first attempt to comment); OP is commenting on their own question; OP didn't benefit from the association bonus.   The message could go something like this (feel free to rephrase):     Comments shouldn't be used to add important information to the question; if you're adding information useful for your question to be answered, please  your question instead.   Mock-up:    This could also be a great opportunity to teach new users how to reply to comments:     Comments shouldn't be used to add important information to the question; if you're adding information useful for your question to be answered, please  your question instead. If you're replying to a comment of another user, you can use @username, where username is the username of the user you're replying to without spaces, to notify the user of your reply.   Mock-up:


There is a link on official  to the  of gvedit utility:     NAME   gvedit − simple graph editor and viewer   But what is interesting - this utility is .  I reported  about missed executable.  How to get gvedit (GVEdit Graph File Editor) for Ubuntu?


For how many ones is $N =11\dots1$ prime?

Suppose $N=111\dots1$ ($n$ ones). For which numbers $n$ is $N$ prime?  $n \ne 1, 3k$ is all progress I have made!


An interesting thought struck me today, can sound be recovered? I mean sounds from the past, maybe a year or a millennium back.


What do spacelike, timelike and lightlike spacetime interval really mean?

Suppose we have two events $(x_1,y_1,z_1,t_1)$ and $(x_2,y_2,z_2,t_2)$. Then we can define $$\Delta s^2 = -(c\Delta t)^2 + \Delta x^2 + \Delta y^2 + \Delta z^2,$$ which is called the spacetime interval. The first event occurs at the point with coordinates $(x_1,y_1,z_1)$ and the second at the point with coordinates $(x_2,y_2,z_2)$ which implies that the quantity $$r^2 = \Delta x^2+\Delta y^2+\Delta z^2$$ is the square of the separation between the points where the events occur. In that case the spacetime interval becomes $\Delta s^2 = r^2 - c^2\Delta t^2$. The first event occurs at time $t_1$ and the second at time $t_2$ so that $c\Delta t$ is the distance light travels on that interval of time. In that case, $\Delta s^2$ seems to be comparing the distance light travels between the occurrence of the events with their spatial separation. We now have the following definitions:  If $\Delta s^2 <0$, then $r^2 < c^2\Delta t^2$ and the spatial separation is less than the distance light travels and the interval is called timelike.  If $\Delta s^2 = 0$, then $r^2 = c^2\Delta t^2$ and the spatial separation is equal to the distance light travels and the interval is called lightlike.  If $\Delta s^2 >0$, then $r^2 > c^2\Delta t^2$ and the spatial separation is greater than the distance light travels and the interval is called spacelike.   These are just mathematical definitions. What, however, is the physical intuition behind them? What does an interval being timelike, lightlike or spacelike mean?


Ubuntu 20.04 Failed to Set MokListRT: Invalid Parameter

I have a MacBook Pro and only use Ubuntu on it. I just upgraded from 18.04 to 20.04. Now when I start the computer it says: Failed to Set MokListRT: Invalid Parameter Could not create mokListRT: Invalid Parameter Importing MOK states has failed: import_mok_state() failed: Invalid Parameter Continuing boot since secure mode is disabled.  Does anyone know EXACTLY how I can fix this?? Step-by-step process I don't want to mess anything up trying to fix this.


Cycles Emission Render Layer Issue - Emission Objects appear in final render as if they have xray

This is a resubmitted question as my previous one was buried and forgotten.  I will describe this as simply as I can.  I have 1 cube and 2 icospheres in my scene. The cube is on layer 1. The isospheres are on layer 2. I have one icosphere in front of the cube and one behind it. However in my final render, the icosphere behind the cube appears in front of cube, as though it has x-ray checked.   I realize there are many things that would work here, but I am doing a very complicated animation and all of the quick fixes for this will not work. Masks, material and object indexes will not work. Alpha over is also out because in the animation, objects will be inside of other objects. Image 1 is a cube with two icospheres. The dark grey is the cube. The blue ones are the icospheres. The cube is on layer 1. The icospheres are on layer 2. I want to blur layer 2 and only layer 2. The blur does show up in image 1, but as you can see the left icosphere, which is behind the cube is visible. That is the problem. Image 3 is my node setup.  Here is the .blend file ,       Please help, Thanks


How to make \dots from amsmath and ellipsis work together

The amsmath package changes the \dots command to have different vertical alignment depending on context (I'm not sure if it does anything else to it). The ellipsis package changes the \dots command to ensure correct spacing in certain textual contexts. However, it seems to undo the changes made by amsmath. Is there a way to make the features work simultaneously?  The following is an mwe:  \documentclass[a4paper]{book}  \usepackage{amsmath} \usepackage{ellipsis}  \begin{document}  a \dots{} b  a\dots{}b \[a + \dots + b\]  \end{document}   If the ellipsis package is used, the ellipsis in math is not vertically centered. If it is not used, there is an extra (thin?) space after the ellipsis in the text. The order of \usepackage's do not seem to matter.


Prove that $\limsup_{n \to \infty} \left(a_n + b_n \right) \leq \limsup_{n \to \infty} a_n +\limsup_{n \to \infty} b_n$

I want to prove that for two sequences, say $a_k$ and $b_k:$  $$ \limsup_{n \to \infty} \left(a_n + b_n \right) \leq \limsup_{n \to \infty} a_n +\limsup_{n \to \infty} b_n$$  If we let $M_n =\sup \{ a_k : k \geq n \}$ and $N_n = \sup \{ b_k : k\geq n  \} $, then obviously  $$a_k +b_k \leq M_n+ N_n \Leftrightarrow  \sup \{a_k+b_k: k \geq n \} \leq M_n + N_n$$  After that, the order limit theorem should suffice, right? Thanks.


I would like to achieve such a result in Blender cycles My goal is to reach a glass texture with slight touches of irridescence. I figured out how to make something purely irridescent or purely glass but I didnt manage to give the impression of a slight irridescent touch. As if the irridescence was only on some little parts of my texture. So please, if you got any hints it would be of great help. Many thanks, stay safe.


Getting number from QLineEdit and passing it to buffer function in PyQGIS?

I am developing a plugin which finds buffer. In that i am using lineedit for getting distance from the user and pass it to the buffer function. My current code throws an error "'QLineEdit' object has no attribute 'Value'. I had also attached my code for reference.   def run(self):     """Run method that performs all the real work"""     # show the dialog     self.dlg.show()     # Clear the QcomboBox before loading layers     self.dlg.Statecombo.clear()     self.dlg.Citycombo.clear()     self.dlg.DistancelineEdit.clear()     layers = self.iface.mapCanvas().layers()     for layer in layers:         if layer.type() == QgsMapLayer.VectorLayer:             idx = layer.dataProvider().fieldNameIndex( 'name_1' )  #this field contains state names             uv = layer.dataProvider().uniqueValues( idx )              """Adding the state names to the combo box"""             for i in uv:                 if i:                     self.dlg.Statecombo.addItem(str(i))               QObject.connect(self.dlg.Statecombo, SIGNAL("currentIndexChanged(int)"), self.findTheCityNames)             QObject.connect(self.dlg.Citycombo, SIGNAL("currentIndexChanged(int)"), self.calcDistance)  # Run the dialog event loop     result = self.dlg.exec_()     # See if OK was pressed     #if result:     if result:         distance = self.dlg.DistancelineEdit.value()         new_distance = distance         number = self.dlg.number_buf.value()         QgsGeometry.buffer(new_distance , 2)                     pass  def findTheCityNames(self):     self.dlg.Citycombo.clear()     ct = self.dlg.Statecombo.currentText()     st = "name_1='"+ct+"'"     exp = QgsExpression(st)     fidAndVal = {}             #QMessageBox.information(self.iface.mainWindow(), "info", st)       layer = self.iface.activeLayer()      iterFeat = layer.getFeatures()      for f in iterFeat:         val = exp.evaluate(f)         if bool(val):             attrs = f.attributes()             idx = layer.fieldNameIndex('name')             cityName = f.attributes()[idx]             fidInt = f.id()             fidAndVal[fidInt] = cityName      for x in fidAndVal.keys():         self.dlg.Citycombo.addItem(fidAndVal[x])   def calcDistance(self):     pass


I started a HDHP medical plan and HSA account on 1/1/2019. We then had our first child on 1/8/2019. The OB/GYN office took a prepayment for the delivery services before 1/1/2019. So the question is: can I claim the part of the bill that I prepaid as an HSA distribution since the service date was after the creation of the HSA even though the payment date was before creation of the HSA?


How can I display a taxonomy term's parent ID in Views?

I am using a JSON plugin to Views to output taxonomy terms as a JSON object for Javascript manipulation. I was to be able to include the parent ID in this output.  In view I see "Taxonomy term: Parent term" under relationships and I have added that to the view. But under "Fields" -> "Add" there is still no "Parent term" listed in the available fields. I'm pretty sure the "pid" should be available. Is there some other way of accessing that field via the Views UI?


We're doing a school project where we have to measure weight on a fitness machine.     The user can select how many weight plates to use by moving a rod like shown in the picture.  How would you do it?  We've talked about the following solutions:   a strain gauge measurement unit beneath the stack, be we doubt that it will be robust, and it will be expensive.  an IR distance sensor that counts the spaces between each plate.  inductive proximity sensors Some kind of electromagnetic solution?


I am writing a Tic Tac Toe game with two files, one for a TTT object, and another for the main method to run the actual game. Everything is working fine except for my win/draw method. I am creating strings out of all the possible winning lines which is also working correctly. However, my logic to return an "X" or an "O" is not functioning properly. In my main method for the game, I can print a win combination and it will successfully print either an "XXX" or an "OOO" but the method isn't correctly recognizing that and using it for the conditions. Pseudo for win/draw method: Create 8 different strings from each winning combination Check if any of them are equal to "XXX" or "OOO" if so, return "X" or "O" public class TicTacToe {  //Enum data type for board states public enum states {      X,     O,     EMPTY;      } //2D Array for board private static states[][] board = new states[3][3];  //Method constructor public TicTacToe() {     for(int i = 0; i < 3; i++) {         for(int j = 0; j < 3; j++) {             board[i][j] = states.EMPTY;         }     }    }  //Method to display the board in console public void displayBoard() {     System.out.printf("%5s  %5s  %5s\n\n%5s  %5s  %5s\n\n%5s  %5s  %5s\n\n",              board[0][0], board[0][1], board[0][2],             board[1][0], board[1][1], board[1][2],             board[2][0], board[2][1], board[2][2]);                                                  }  //Method to set a board position to X or O public void setBoard(int row, int column, states i) {     if (board[row][column] == states.EMPTY) {         board[row][column] = i;     }     else {         throw new RuntimeException();     }   //Method to check for a winner or draw public String winDraw() {     String row1 = board[0][0].toString() + board[0][1].toString() + board[0][2].toString();     String row2 = board[1][0].toString() + board[1][1].toString() + board[1][2].toString();     String row3 = board[2][0].toString() + board[2][1].toString() + board[2][2].toString();     String col1 = board[0][0].toString() + board[1][0].toString() + board[2][0].toString();     String col2 = board[0][1].toString() + board[1][1].toString() + board[2][1].toString();     String col3 = board[0][2].toString() + board[1][2].toString() + board[2][2].toString();     String diag = board[0][0].toString() + board[1][1].toString() + board[2][2].toString();     String antiDiag = board[0][2].toString() + board[1][1].toString() + board[2][0].toString();          if(row1 == "XXX" || row2 == "XXX" || row3 == "XXX" || col1 == "XXX" || col2 == "XXX" || col3 == "XXX" || diag == "XXX" || antiDiag == "XXX") {         return "X";     }     else if(row1 == "OOO" || row2 == "OOO" || row3 == "OOO" || col1 == "OOO" || col2 == "OOO" || col3 == "OOO" || diag == "OOO" || antiDiag == "OOO") {         return "O";     }     else {         return null;     } }  }


Polynomial satisfying $f(x) = f'(x) \cdot f''(x)$

If a polynomial of degree $n$ satisfies $f(x) = f'(x)\cdot f''(x)$ (such that $n$ belongs to $\mathbb R$) then $f(x)$ is?  A) an onto function   B) an into function   C) no such function possible   D) even function   I tried this question by letting a polynomial $f(x) = ax^n + bx^{n-1} \cdots$ and then derivated it but it did not help much , then i assumed a quadratic expression $ax^2 + bx + c$ and got $ax^2 + x(b-4a^2)$.


Major differences between Hardtail and Full Suspension mtn bikes

I'm curious as to the big differences in the feel and ride of a hardtail vs a full suspension mountain bike. Also, which types of riding/trails are each better suited for?


I'm trying to backup a linux system to an IMG file that I can then boot and run in QEMU.  NOTE: I have tested on Lubuntu and tiny core linux.  The process I have followed is:    I have 2 hard disks, sda and sdb partition sdb1 and mount sdb1 partition in /mnt/sdb  dd an empty file the size of sda to IMG file in the mounted sdb directory. dd if=/dev/zero of=/mnt/sdb/disk.img bs=x count=1 - x being the size of sda I then use fdisk on sda to output the disk layout to a script file and then load that into the disk.img file  Then mount it and copy the contents - losetup -P -f disk.img  find the loop device      e.g /dev/loop36  0  0   0 0 /mnt/sdb/disk.img  0   512  created the filesystem on the first partition of the loop device - mkfs.ext2 /dev/loop36p1 mount the partitioned loop device - mount /dev/loop36p1 /mnt/img then copy the bootsector - dd if=/dev/sda of=disk.img bs=512 count=1 conv=notrunc finally I used rsync to copy over the filesystem to the /mnt/img directory, I've had varying success with this. using:   $ rsync -aHxv / \    --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found"} \    /mnt/img     I've tried the exact  process using Lubuntu as shown above, the rsync command worked however when I try and run the IMG in QEMU it hangs at booting from the hard disk.   When trying the process above in tcl - the rsync command fails and when I try to boot in QEMU it says there is no bootable device.  Does anyone have any advice regarding this? or has done similar things and has a better method to achieve the goal?


How to replicate photoshop's text highlight blending mode

It blends with lower layers in difference mode, I know, but how can I achieve this "distorted color" effect it produces on highlight areas? (the orange and magenta areas)


compilation error while trying to define a generic array

public class foo<T> {      protected T[] arr;      public foo() {         T[] f = new T[5];     } }   I have two questions:    "Cannot create a generic array of T", I get this error for T[] f = new T[5];.  Why can't I create a generic array?  If that's not possible, why can I declare a reference to a generic array? I don't get compilation error for the decleration: protected T[] arr;


Can we leave the Dubai airport during a long layover; do we need a visa?

My friend and I have a 10 hour layover In Dubai. I was wondering could we visit Burj Khalifa in that time. Only problem is that we are arriving at the airport at 23.20h and it is on Monday. We don't want to go at the top of the building, only to see it. I was wondering if it's safe to walk at night, and do we have enough time for that? We are from Serbia, and I don't know if we need visa for that.


Drupal 8 create a template override for a view block within a custom module

The Question:  In Drupal 8: How do I add a template override for a view block and have that twig file reside in a custom module - not my theme?  Further Information:  I have already created a custom module that creates a content type, imports data from an RSS feed and generates nodes into the content type it created.  The module also contains a view YML file so that the view for my content type is created when the module is installed.  The view only has one display which is a block.  I would like to create a template override for the block and house the template override within the module (rather than within my theme).  The template override does the following:   Adds the appropriate classes to the block Adds an image beside the block title when the title is displayed Wraps the {{ content }} in a div with an appropriate class Loads the custom module's library to apply CSS   The goal is to have a module that a non-technical person can install, assign a block to the desired region and have all the templates, CSS, JS, etc pull from the module.  I don't want them to have to copy a template into their theme, etc.  I want the block to be a view so that the user can use the Views UI to make any desired updates to the view block's fields, number of returns, etc.  I was able to get Drupal to recognize the template by using hook_theme_registry_alter() but the variables from the block are null.  Both the {{ label }} and {{ content }} are null when I kint them in the template override.  Here is the hook_theme_registry_alter() code:  /**  * Implements hook theme_registry_alter  **/ function MYMODULE_theme_registry_alter(&$theme_registry){   $theme_registry['block__views_block__MYVIEW_block_1']['path'] = drupal_get_path('module','MYMODULE') . '/templates/';   $theme_registry['block__views_block__MYVIEW_block_1']['template'] = 'block--views-block--MYVIEW-block-1'; }   It should be noted that when I used hook_theme_registry_alter() for a view page template override in my module it worked.  My guess is that the variables were pulled from the page alias.  Please include detailed information because I am still learning about the various hooks and how variables are passed.  Thanks in advance!


is there a basic custom application with Apex classes and a few visualforce pages to get started?

I am looking to jump-start custom application development for salesforce. I am hoping that there is a skeletal apex application (similar to basic hello world web apps for j2ee or node.js platform) that  I could import into my Eclipse ( with Force.com plugin) and begin incrementally adding  pages and features.


Someone on Math.StackExchange got the Informed badge several hours ago, but it still shows 1/1 for Informed:    This is weird, because normally, the next badge already says that you got it while you didn't get it already. It is also weird that after several hours, it hasn't been fixed if it was catching.   I've found several cases of this on Math.SE and StackOverflow. It also happens in the Autobiographer badge where the badge was awarded 15h ago.


Say we have a simple circuit with three resistors in series, each of which have the same resistance. We also have a battery with a given constant potential difference hooked up in series with these resistors.  According to Ohms law and Kirchhoff's law, the current passing through each of the resistors will be    Determined by the sum of the resistances of the resistors  (V/(Total R) = I) Constant, as there is only a potential difference drop for each resistor in series.   So the amount of charge passing through each resistor is always constant, just like water flowing through pipes.  But the "pressure" on these electrons decreases- meaning that the amount of energy each electron has is reduced, part of their energy converted into energy for the element that the resistor represents to use (electrons doing work.)  So logically, this should mean that the speed of each electron is reduced, and that extra energy they once had in kinetic energy is the energy used on the element.   So if this is the case, how is it possible that Current stays constant? Yes, by the definition Q/t current is constant because the number of electrons passing through a point is the same, but by the more involved definition I=nqAV, current is reduced because the drift velocity must be reduced, or else no work could be performed.  Where is my intuition wrong?


Are there any modules available or any procedures available so that node reference fields can be incorporated into a ?


Does the proof of rank-nullity theorem from Lang's "Linear Algebra" involves axiom of choice?

Disclaimer: I never had (yet c:) a rigorous exposure to set theory (independence proofs, and similar stuff...). I was wondering if, in the following proof of the rank-nullity theorem form Lang's "Linear Algebra" book (page 61, theorem 3.2 in the third edition), the author makes use of the axiom of choice:  Let $V$, $W$ be vector spaces and let $L:V \to W$ be a linear map. Then we have $\dim V = \dim \ker L + \dim \text{im}\, L$. Proof: Let $n$ be the dimension of $V$, $q$ the dimension of the kernel of $L$, and $s$ the dimension of the image of $L$. Then, assuming $s > 0$, let $\{w_1,\dots, w_s\}$ be a basis of $\text{im}\, L$; let $v_1,\dots,v_s$ be $s$ elements of $V$ such that $L(v_i) = w_i$ for $i = 1,\dots, s$. [...]  Here, the inverse image $L^{-1}(\{w_i\})$ need not to be unique, but the author claims that he can arbitrarily take $s$ elements of $V$ such that $L(v_i)=w_i$; this can be carried out with a choice function $\varphi: \{L^{-1}(\{w_i\}): i = 1,\dots, s\} \to V$: we have our $\{v_1,\dots, v_s\}$ by considering the image of $\varphi$. Is the axiom of choice (or any weaker equivalent) required in this case?


Restroring MYSQL databse from .frm and .ibd files (database does not exist error)

please help ...  I want to restore MYSQL database using .frm and .ibd files (that's all I am having). here is additional information..     I reinstalled same version of WAMP without taking backup of mysql data. Now i am remain with "BIN" directory which contains some .frm and .ibd files. When i opend phpmyadmin i can find  My old database and table names in browser but when I click on it it says "'xyz'table doesn't exist". But exceptionally one of table is working and displaying it's data. all my tables were of  innoDB.


How do I unload (reload) a Python module?

I have a long-running Python server and would like to be able to upgrade a service without restarting the server. What's the best way do do this?  if foo.py has changed:     unimport foo  <-- How do I do this?     import foo     myfoo = foo.Foo()


Checkered / square-patterned copper plane on a PCB

The Verge  photos of the original iPhone "dev kit".  The board looks like an ordinary development kit to me, however there is a strange pattern of squares on the topmost layer. I know only of solid and hatched variants of a copper plane.  What could be the reasons to use such a pattern on a copper plane?   Aesthetics? EMC? Obfuscation?


Okay, I understand how I may use apt-get {install|upgrade|remove} mypackages to install, upgrade, or remove binaries as well as their configuration data files and dependencies (actually, remove will only remove the binaries unless additional flags are provided).  I am not looking for how it is used as the man describes this, but high level what it is doing.  My end goal is to create a means for me to install and manage some custom software (created by a make file) on multiple remote machines, and I need to learn more about the process.  If answers to this question are based on which distribution is used, please tailor to Debian.  In addition to generally how it works, I have the following specific questions:   How does the client that is accessing the apt repository keep track of the files? Must the repository be hosted on the same operating system (i.e. can apt repository be hosted on redhat)? How are the locations to install files specified?  Is this specified by the .deb file? How is a remote machine accessing the repository?  Is it just ftp(s) or http(s)? Is the machine that is hosting the repository running special software (like gitlab for a git repository), or is it just some structured file system?


What are the badges I can earn on each site, and what are the exact criteria for earning each badge?

Formerly List of all badges with full descriptions.  What are badge name's requirements? Why didn't I get badge name ? Which badges can I earn multiple times?    Jump to:                    Note: Some badges are awarded based on score. The term score means the total number of upvotes minus the total number of downvotes.  Any badge with a *** next to it is one of 20 badges that count towards the  displayed on a moderator candidate in an election. The candidate score is a total of 40 points: the first 20 are awarded based on the user's rep divided by 1000 and rounded down; the second 20 represents the total number of unique badges earned of the 20 that count. Note that if the same badge is earned multiple times, it will only count once towards the candidate score.  Any badge with a "(retired)" next to it is no longer awarded, but is retained by users who previously earned them. See  for more info on what it means for a badge to be retired.       Visit the  of the  on any site to see a complete list of badges that you can filter by earned, unearned, or type.


how to update variables, passed to a method?

when i pass variables to my method they are not updated in the main code, but only passed to the method. how to do that once passed variable would update in main code?   Thanks!  //////////// here is main code: public static  class MyCoding extends MainScreen{ static int mee=1;         public static void myCode(){         Status.show("mee="+mee, 2000);   // shows me=1         Moo.moo(mee);         Status.show("mee="+mee, 2000);// should be mee=76547545 but still shows mee=1 !      } }   //////////// here is my method:  public static  class Moo extends MainScreen{     public static void moo(int bee){         mee=76547545;          return;     } }   What to do? Thanks!


Why do we need Auto-encoder? How is it useful in real life implementation?

From what I've learned about autoencoder is it takes an input and predicts an output almost similar to the input. So, if it outputs the same thing with the same dimensions, what is the benefit of using autoencoder then? We can directly work with the inputs.


Why does operation on a specific index on matrix affect affect all elements with that row

My code is supposed to initialize an n*m matrix of all zeros in order to manipulate them individually edits = [[0] * (len(str2) +1)] * (len(str1) + 1)  However, when I try and set a specific index in that matrix like: edits[0][0] = 1  It affects all value with that column value [[1, 0, 0, 0, 0], [1, 0, 0, 0, 0], [1, 0, 0, 0, 0], [1, 0, 0, 0, 0]]


Ok, I have no trouble setting up my server, or connecting to said server with my personal machine, but when my friend attempts to join we get this message:  Internal client error: java.net.UnknownHostException: session.minecraft.net   A quick google search seems to suggest that this is because his version is different than mine, except he's running MY FILES. (I copied my .minecraft folder and transferred them to his laptop, then we had him login once using his credentials to finalize the transfer)


Apply a modifier as a shapekey into existing shapekey or merge shapekeys?

I am making a shapekey of a model shrinkwrapped to another model. The shrinkmap modifier is too inaccurate to wrap to the model alone. So, my first step was to roughly hand position the geometry around of the first model around the second, then use shrinkwrap. The rough positioning was done as a shape key. I can then apply shrinkwrap, but its as a separate shapekey. The two do not work well together. I need them to be the same shapekey. How do I apply a modifier to an existing shapekey, or merge/combine/join the two shapekeys?


Mine and other players skins not loading

I can't see skins anymore. Everyone including myself is either a Steve or an Alex. I've tried looking up solutions and asking friends, but nothing is working. I think this started around 1.9-something. No matter what I try I can't get skins to work. I've relogged, reinstalled Minecraft multiple times, changing my skin, and using texture packs. Nothing I've tried fixes it. Any nerds know what's going on?


I am using the align environment, but wish my numbering of equations to be on the left-hand side of the page. Is there an easy way to do this?


I am executing the query with "where exists" using one table in MySql. It works fine with SELECT *, but fails when I try to do DELETE instead of SELECT *.   How to perform the same query with delete? Many thanks in advance!  select * from MyTable t1 where exists (  select * from MyTable t2 where t1.user_id = t2.user_id  and t1.object_id <> t2.object_id and t2.role = "ADMIN") and role = "ORG_MANAGER"  and object_type = "type_b";


Two interactions are individually signifcant, but not when included together

So I have two interaction terms (ordinal x ordinal--treating each as continuous) I'm trying to test in a logistic regression model. Interaction 1 is significant--but not when Interaction 2 is present. Likewise, interaction 2 is significant--but not when interaction 1 is included. I thus went ahead and tried a 3-way interaction, but it wasn't significant either. Not sure how to interpret this (do I have to choose one 2-way interaction?), so would appreciate some input. See below for screenshots of what I'm referring to.


Recently I got a virus on my computer that completely wiped the hdd. I am trying to install windows xp to this: DV7-636bus laptop from HP, and I get the following BSOD:  A problem...............and Then Select Safe Mode.  Technical Information:  ***STOP: 0x0000007E (0xC0000005,0xF73B9D66,0xF78D1EA0,0xF78D1B9C)  acpi.sys - Address F72B9D66 base at F73AE000, Datestamp 480252b1   Does any one know of a solution for this?


How do I change where Steam installs to?

I had a problem with Steam a while ago and had to re-install it. When I re-installed I somehow set it to install on my desktop and it cluttered my desktop with all of the files. I moved all of files into one folder and started up Steam, and on starting up it created all of the files again on my desktop after I had just moved them into one folder. I know the default install is C:\Program Files\Steam but mine is set to my desktop, so is there anyway that I can change it back to there without having to re-install?


How to save bookmarks with names in QGIS?

When I create a bookmark the name and project that I enter are not saved when I click Close.   The manual says there should be an OK button but there isn't. Using QGIS 1.8


Could Alpha Centauri be made of anti-matter?

How can we tell if a star is made of matter or anti-matter? For example, is there any difference spectroscopically? Or could we tell from cosmic rays?  If half of the stars were made of matter and half of anti-matter, then they would be in balance.   After the Big Bang, the slightest of imbalances in the distribution of matter and anti-matter would, I think, grow more pronounced as a local surplus of matter would persist if bombarded with equal amounts of matter and anti-matter. Over time, that matter would gravitationally come together and locally grow more dense. Gravitation thus would segregate matter and anti-matter as most of space became empty. Thus perhaps half the stars that we see might be made of anti-matter.  For the photons they produce would be the same, yes? And the gravitational force is the same.  In particular, I wish to know approximately what is the density of mass in the space midway between our solar system and Alpha Centauri? What would be the nature and magnitude of energy released there if matter from our side was colliding with anti-matter from Alpha Centauri's side? Would we be able to detect that? Please, I would like to see a calculation!


"whitened", "blackened", and "reddened"; but "yellowed", "grayed", and "blued".  Is there some rule or is it just one of those things?  "Greened" makes sense; no one is going to say "greenened".  "Pinked" or "pinkened"?  "Purpled" or "empurpled"?  First person to not make an Arrested Development joke gets a +1 from me.


How to find backdoor that is adding code in my /includes/theme.inc file?

I got a "site may be hacked" warning from Google in one of my Drupal sites and while working to resolve this, I noticed that a hacker gained access to the /includes/theme.inc folder and added codes inside the template_process_html(&$variables) function   I commented out the part that was adding links on my site and kept it as it is. Now after 2 days I checked the site again and saw that another set of codes are inserted in the same function which now looks like this:  // Render page_top and page_bottom into top level variables.   $variables['page_top'] = drupal_render($variables['page']['page_top']);   $variables['page_bottom'] = drupal_render($variables['page']['page_bottom']);   // Place the rendered HTML for the page body into a top level variable.   $variables['page']              = $variables['page']['#children'];   $variables['page_bottom'] .= drupal_get_js('footer');   if($variables['classes_array'][1]=='front')     $variables['page_bottom'] .= '
The beginning of the process you should find some nice bargains is the internet. You could possibly find a websites selling such designer shoes at much reduced prices. You will, therefore, need to observe a quantity of sites and compare prices before finally settling for the offer it is possible to comfortably have. However, you have to remember that you won\'t have the chance to try the shoe you want to purchase. Additionally you need always be wary from the online sale scams.Custom Cheap Jordans is genuine. There are 24 customized versions of Jordans. You can buy, Jordan, does not have any for good quality, very supportive shoes to wear while to the basketball judge. They come in various colors, market, they are generally have a great performance top basketball shoes, 72-10 11s for sale Michael Jordan famous. Women Air Jordan Shoes are designed with women\'s basketball players read more was formed. With superior quality materials and design ...... 100s of links here      $variables['head']    = drupal_get_html_head();   $variables['css']     = drupal_add_css();   $variables['styles']  = drupal_get_css();   $variables['scripts'] = drupal_get_js();   So now it is clear that site has a backdoor, I need to find that backdoor to keep my site clean and remove that warning from Google.


Why I don't have to enter my password while Sign In (no password save in browser)?

I found that login in to Stack Exchange from another device put my privacy under risk. I can press Log Out button but I don't have to enter my password any more. This is insane!  The problem is that I forgot my registration email and accidentally created another account. Now I cannot sign out from this account to sign in to another. This UX makes so much pain to user.


How do I forward a local port to a remote port through SSH?

For example, I want to bind localhost:2222 to remote:22  I want to be able to do this:  ssh user@localhost -p 2222   and end up on the remote server via SSH  Is this something that can be done using SSH?  All of the examples I've seen are around port forwarding from a remote machine elsewhere.  I just want to port forward LOCALLY to a remote server.  Edit: this is NOT a duplicate of the suggested duplicate.  I am not trying to access a port on a remote machine via a local port.  I just want to alias port X on my machine to 22 on a remote machine.  I'm not trying to tunnel here, which I thought was clear by my example.  Edit2: it it makes it more clear, I essentially want to proxy localhost 2222 to a remote server on port 22.


This is just an easy question!  I want to lean some objective-c but the problem I don't have a mac I've only PC with windows  is there any compiler and editor where I can type my code and run it on windows.  Thanks in advance.


Why grep --include with curly braces fail in subshell?

This works in shell:  grep -R --exclude-dir=storage --exclude-dir=node-modules --include=*.{scss,css} loader.gif   But this fails:  sh -c "grep -R --exclude-dir=storage --exclude-dir=node-modules --include=*.{scss,css} loader.gif"   It fails without any message, it just can't find any occurrence.  This works:  sh -c "grep -R --exclude-dir=storage --exclude-dir=node-modules --include=*.scss loader.gif"   Why the use of curly braces in --include=*.{scss,css} fails?


How to georeference PNG images using QGIS?

How can I georeference png images using QGIS, running on OSX?   I've looked at ExifTool, and the plugins GeoTag and Import Photos + Photo2Shape. These tools (and other answers) as far as I can tell all use georeferenced images or images with EXIF data. I would like to load the png somewhere, and drag it around on a basemap from OpenStreeMap to position it where it should be. I know the general location, and just need to position it.   (I think I know the projection, but will find out if that is the case. The images are of an area ~500m x 200m so the projection variation will hopefully not matter hugely if I am incorrect).


How to Add maximize button to the OOB forms in SharePoint 2013

In SharePoint, when we edit, view or Add an item in lists or libraries we observe that we do not find maximize button in SharePoint 2013. How to I add the maximize button to all the lists and libraries form as we see in SharePoint 2010. I need a generic answer.  Thanks in advance.


Is there any way of saving this blurry photo???

Is there ANY way to save this blurry photo? I have photoshop. PLEASE HELP.


Show that the cardinal of $ A := \left\{ k \in \mathbf{Z} | 0 \leq k \leq n \text{ and } \binom{n}{k} \text{ is odd} \right\} $ is a power of 2

Let $ A := \left\{ k \in \mathbf{Z} | 0 \leq k \leq n \text{ and } \binom{n}{k} \text{ is odd} \right\}  $.   I must show that the cardinal of $A$ is a power of 2.  I have tried to show that there exist a bijection between $A$ and the set of subparts of another set, but unsuccessfully.  I also thought about trying to show that the cardinal of $A$ must divide the cardinal of $ P(\left\{ k \in \mathbf{Z} | 0 \leq k \leq n \right\}) $ (it is $ 2^{n+1} $), which would ensure the result, but I do not think this a good path.  Are there simple arguments to show that ?


What is an example of a sequence $X_1,X_2,...$ such that $X_n\rightarrow X$ in probability, but $\mathbb{E}(X_n)$ does not converge to $\mathbb{E}(X)$?


Prove that a closed subspace of a Banach space is also a Banach space. Show that the linear space of all polynomials in one variable is not a Banach space in any norm.


Google Websmasters - How to provide last updated date

One of my e-commerce sites with daily product uploads has sitemap listed has below. Recently we notice that google index rate  has slowed down.   <url> <loc> http://urllink </loc> <lastmod>2016-07-22</lastmod> <changefreq>daily</changefreq> <priority>0.5</priority> </url>   Could it be because our automatically generated site map structured, wherein lastmod date is being shown as the previous date every day i.e. it tells google that this product has been changed the previous day when in fact it hasn't been. Does that mean Google will expend resources, try to see what has changed and if it hasn't changed it probably will starting assigning lower priority to our site and hence we run the risk of our more recently added products not being indexed.  We also have a feeling that this lastmod date error is probably eating a lot of our server resources too.   Hope that was clear. Thanks


Ubuntu 12.10: Package libc6-dev-i386 is not available

I'm building 32 bit boost thread libraries on 32 bit Ubuntu 12.10. When building I get the error /usr/include/gnu/stubs.h:7:27: error: gnu/stubs-32.h: No such file or directory  I googled the problem and from reading  it seems I need to install libc6-dev-i386. However, when I run sudo apt-get install libc6-dev-i386 I get:  Package libc6-dev-i386 is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'libc6-dev-i386' has no installation candidate   Can anyone help me to locate this package?  Edit, more info:  I'm not sure if this is relevant, but uname -m -p -i gives i686 i686 i686.  ls /usr/include/gnu/ gives libc-version.h  lib-names.h  option-groups.h  stubs-64.h  stubs.h.  ls /usr/include/i386-linux-gnu/gnu gives libc-version.h  lib-names.h  option-groups.h  stubs-32.h  stubs.h.  I added /usr/include/i386-linux-gnu to $PATH but it didn't help, I still get the same error when trying to build the 32 bit boost thread libraries.  More info:  I've now tried this with Ubuntu 12.04 and I'm getting exactly the same behaviour. With this install uname -i gives i386.


UK visa type to attend conference and training in London

I'd like to visit London for a week to attend a conference (2-3 days) and a short 3-day non-recreational training course.  (1) What is the correct type of visa (and subtype) for activities listed above? Training may or may not be the main reason for the visit.   according to VISITORS APPENDIX 3. PERMITTED ACTIVITIES FOR ALL VISITORS (EXCEPT TRANSIT VISITORS)   As a visitor i am permitted to undertake any activities in paragraphs 3 – 27. Can i undertake any of them or just a subset that corresponds to selected visa type/subtype? If i select Visit -> Tourism -> 6 month in visa application form and tell about conference and course then    Can i undertake activities listed in 5 (a) attend meetings, conferences, seminars, interviews; under "Business – general activities" subsection? Can i undertake a short non-recreational course that does not include english language training from 25-b-(ii)? What is an accredited institution? Is there a more appropriate visa type for the visit with a plan that includes activities from paragraph 5(a) and 25-b-(ii)? Can i undertake any activities from paragraphs 4-27? (not 3 A visitor may visit friends and family and / or come to the UK for a holiday) Is "Study - Study (non point-based system) - short-term student 6 month?" a better choice for activities listed in the beginning of this message 5(a) and 25-b-(ii)?    Thanks


Trying to get Sims 4 to work on Ubuntu 16.04


When working within javascript can someone provide me a good reference or explanation over testing for equality/inequality and type coercion?   From what I have been reading I see where there are two principles of thought on using eqeq (==) vs. eqeqeq (===) some feel that you should not use eqeq and always as use eqeqeq as it is safer to use.   I have been playing around with some basic samples and I am having trouble discerning the difference or when best to use one over the other:  For example: here is some basic script I was writing out. When I test using eqeq or eqeqeq I get the same result. I have not seen an example yet where I would get a different results (ie. using eqeq returns true where eqeqeq returns false).   function write(message){    document.getElementById('message').innerHTML += message +'<br/>'; }   var tim = { name: "tim" }; var tim2 = { name: "tim" }; //objects are equal to themselves ( == vs ==== eqeq or eqeqeq) write("tim eq tim: " + (tim == tim)); //returns true  //objects are only equal to themselves regardless of containing value got that write("tim eq tim2: " + (tim === tim2)); //returns false  //access the primative type to test true or false write("tim value eq tim2 value: " + (tim.name === tim2.name)); //returns true //how does this differ in efficency over the eqeq operator? is one safer to use over the other? //write("tim value eq tim2 value: " + (tim.name == tim2.name)); //also returns true  //testing primatives  write("apple eqeqeq apple: " + ("apple" === "apple"));  //true write("apple eqeqeq apple: " + ("apple" == "apple"));  //true   Can someone provide an explanation or reference I can read that helps clarify this a bit more.  cheers,


Book about actress forced to disguise alien murderer

I read this book once when I was in middle school. A girl solves a murder or a mystery on a spaceship. It was a thin paperback books.   All I can remember is that there was an alien, and there was a movie star or actress or famous makeup artist on the ship traveling with another woman. By the end of the book the murderer was the woman the actress was traveling with who forced her to use her makeup skills to disguise her, and she was really some kind of alien.


How to put last modified date in blog post on Blogger?

I want to have last modified date on my blog post on Blogger.com. I have tried  but it didn't work out since this solution is for the old Blogger.com   Edit-1: I got to know about this meta tag   <meta http-equiv="last-modified" content="YYYY-MM-DD@hh:mm:ss TMZ" />   But I don't know where to put this meta tag in specific post and how it works ?


Why is there a time limit for changing the username?

Is there a reason a limit is imposed on the number of times you can change your username?


Adding class with click and capturing added class

After the page is loaded, I can add a class with jquery as follows. $(document).ready(function() {     $("#parent").click(function(){         $(".child").addClass("active");     }); });  but I can't catch the click on the added class, it doesn't work. $(".child.active").click(function(){     alert('this is clicked'); });  would you please help me.


Prove that $n$ divides $\phi(a^n -1)$ where $a, n$ are positive integer without using concepts of abstract algebra

I need to show that $n$ divides $\phi(a^n -1)$ where $a, n$ are positive integer without using concepts of abstract algebra  I know that $$a^n\equiv 1\pmod {a^n-1}$$  How do I proceed from there?


How do you prove Well-Ordering without Mathematical Induction? (and vice-versa)

Here is my attempt to prove the Well-Ordering Principle, i.e. that any non-empty subset of $\Bbb N$, the set of natural numbers, has a minimum element.  Proof. Suppose there exists a non-empty subset $S$ of $\Bbb N$ such that $S$ has NO minimum element. Define $A = \left\{n\in \Bbb N : (\forall s\in S)(n \leq s)\right\}$. It is obvious that $1\in A$. Suppose $n\in A$, then for each $s \in S$, there exists $q \in N$ such that $n + q = s$. Since $q \ge 1$, $n+1 \leq s$, for all $s\in S$. By Principle of mathematical induction, $A = \Bbb N$. Take any $s_0 ∈ S$, then $(\forall s\in S)(s_0 \leq s)$. (This contradicts that $S$ has no minimum element).  How do I prove the statement without invoking Mathematical Induction? Also, I read that the proof of Principle of Mathematical Induction makes use of Well-Ordering. Can it be proven independently of Well-Ordering too?


Replace Mint with Ubuntu in dual booting system

I am already dual booting windows 10 with Linux Mint, and I am trying to replace Mint with Ubuntu. I have already created a bootable usb for Ubuntu.  When I try to install Ubuntu, I don't see any option to install Ubuntu alongside windows 10. Rather, I see "install Ubuntu alongside Linux Mint". I didn't find any option to keep my windows 10. How can I replace Mint with Ubuntu in this dual boot system? Mint is installed on an ext4 partition and I have a Linux swap partition.


Rounds fine till 5-6 digits decimal,but only rounds 2 digits

I am making an app, and I used decimal format to round numbers. It worked fine till 5-6 digits but only rounds to 2 decimals.  I made some edits but it didn't work.Till 5-6 digits,It rounds perfectly, i.e.  leaving only 3 decimal places after rounding,but when I go over 7-8,It just rounds two decimal places  This is my code     double result = Double.parseDouble(myEditText.getText().toString());         String i = Double.toString(result);         int int1 = i.indexOf(".");         String io = "0.";         int ii = (i.length() - int1 - 1)-3;         for (int iio = 0;iio <= ii;iio++){              io = io+"#";         }            DecimalFormat decimalFormat = new DecimalFormat(io);         String string = decimalFormat.format(result);         result = Double.parseDouble(string);         textArea.setText(textArea.getText().toString() + " = "+result);     For eg. I input 1.678394762 It gives me 1.6783948, While it should give 1.678 If I input 1.45678,It gives me expected 1.457


Formula for the sum $\sum_{i=2}^{n} \frac1{i^2-1}$

I have to find the formula for sum $$\sum_{i=2}^{n} \frac1{i^2-1}$$ I remember reading somewhere that $\displaystyle \frac1{i^2-1}$ can be shown as $\displaystyle\frac1{i+1}$ and $\displaystyle \frac1{i-1}$.  If I can express it as this, then I should be able to create a telescopic sum, and produce the formula easily.  But how can I get to those two fractions in the first place so that I can build the proof?


This is a question from Hoffman.  Let $V$ be a finite-dimensional vector space over the field $F$ and let $T$ be a linear operator on $V$. Let $c$ be a scalar and suppose there is a non-zero vector $\alpha$ in $V$ such that $T\alpha=c\alpha$. Prove that there is a non-zero linear functional $f$ on $V$ such that $T^tf=cf$.  I know that essentially I need to prove that there exist an $f$ such that $fT(\beta)=cf(\beta)$ for all $\beta$ in $V$.   What puzzles me is that there doesn't seem to be anymore information on the linear transformation $T$ other than the fact that there is a non-zero vector $\alpha$ in $V$ such that $T\alpha=c\alpha$; we have no idea of what we will get when we let $T$ operate on vectors other than $\alpha$ in $V$.   It therefore seems that there is a certain $f$ that can ignore the effect of $T$ somehow,but I can't find that $f$.


I often see experienced programmers write !!x, even though the expected expression is a Boolean (i.e., zero or not zero) and not an integer. For example, a line from boost: BOOST_ASSERT(!!p); // where `p` is a pointer  What's the point of !!p when just p will do? What I understand by a Boolean parameter is an expression converted to a value of integral type, and the value is compared against zero, explicitly or implicitly (with if or its ternary operator equivalent). Thus, anything that takes a Boolean and expects only 0 or 1 is wrongly implemented, if my understanding of Boolean is correct. For clarification: it's obvious that ! converts to bool; the question is explicitly asking for why.


How can I implement a timeout on a function that hangs due to a library function?

I am building a program that verifies media and doc files within a given file tree. When it tries to read a pdf (with PyPDF2), it will occasionally freeze the program. I want to implement a timeout on the function so that it just times out and logs an error rather than crashing. Here is my code for the PDF function:  def pdf_verify(file, good_files, bad_files):     try:         PyPDF2.PdfFileReader(open(file, "rb"))         good_files.append(file)     except:         bad_files.append(file)      return good_files, bad_files   It tries to open the PDF file with PyPDF2, and if it can't be opened, it catches the exception and appends the file to a bad file list. I know there is a way to do this on Linux, but I need the program to be runnable on Windows. Is there any way to do this? Thanks!


Does every group, given for example by its multiplication table, have a matrix representation? If not, how does one proof for a given group that no matrix representation exists?  In addition, as for groups whose elements $g$ can be represented by a matrix $D(g)$ the representation is defined by  $$ D(g_1)D(g_2) = D(g_1g_2) $$  what would be the analogue condition defining non-matrix representations?


Why a file automatically created with '~' whenever I change the gedit file?

Whenever I made changes in my text files, automatically another file with the same name plus a '~' gets created. Why does this happen?  How can I prevent these files from getting auto-created?  These are two files I created and two which got automatically created:


Let $G$ be a group. Prove or disprove that $H=\{g^2~ |~g\in G\}$ is a subgroup of $G$

Let $G$ be a group. Prove or disprove that $H = \{ g^{2} \mid g \in G \}$ is a subgroup of $G$.  From other places on the interwebs, I have found that I should be able to use the Alternating Group $A_{4}$ to disprove $H$, but I don't know how to use $A_{4}$ to do that.  Edit I am not sure how to square elements of $A_{4}$, so I'm looking at the Cayley Table for $A_{4}$.  If I am reading this table correctly, then (1)2=(1), [(12)(34)]2 = (1) , [(13)(24)]2 = (1), [(14)(23)]2 = (1), (123)2 = (132) ...  Assuming I am reading the table correctly, then does the fact that (123)2 = (132) disprove H={g2 |g∈G}?


First, my apologies in advance: this isn't really the type of question StackOverflow is intended for, but I don't know where else to ask.  Looking at the documentation for Java enum, I see this:  class Enum<E extends Enum<E>>   Please help me understand the grammar and semantics here.  I understand that <E extends X> means that the formal type E has to be actual type X or a subtype of X. In this case, X is Enum<E> and that's where my mind loses the thread, since we're defining Enum, and it's the same E.  I bumped into this looking into Enum but my question applies regardless of the class name.  I've studied the Java tutorials on generics but don't see this addressed.  I've looked at the Java language specification in various places but don't see where this kind of recursion is discussed, though perhaps I'm just missing it.


Consider a general arithmetic sequence $x_j = y + jn, j \ge 1$. Prove that if $p$   is a prime number such that $p \nmid n$ then there is some element from the sequence $\{x_n\}_{n=1}^\infty$ that is divisible by $p$.      Your proof of this result should give you a method which for a given arithmetic   sequence and prime actually allows you to calculate a point in the sequence at   which the divisibility property holds. Illustrate your method by presenting an   element from this sequence that is divisible by $p$, where   $p = 150000001 = 1.5 × 10^8 + 1$, and where $n=14506349$ and $y=2021$.   Does anyone have a clue on how to tackle this?


When did it become common to say "because X" instead of "because of X?"

When did this usage become common, especially in a sarcastic or ironic context?     Carnegie Mellon erroneously sends computer science admission letters to 800, because computers. [emphasis added]   (source for example: )


How to recover plaintext, if we know public key(RSA), correctly encrypted text and text encrypted with faulty public key, where one bit is changed?


Literally vs. figuratively: how literally is literally?

I'm sensitive to the fact that in light of recent events, the example discussed in this question may be unsettling to some.  For that, I apologize, but I cannot think of an effective alternative.  In a Modern Marvels documentary on The History Channel, the narrator says, "[...] bombs have evolved into devices that can literally blow mankind off the face of the earth."  It's difficult to tell whether "literally" is appropriate in this instance.  On one hand, the narrator likely uses the word literally to emphasize that although it may have been common for many years to talk about bombs as being powerful enough to blow up the world, in the modern age of weaponized hydrogen fusion it really is possible to eradicate all of mankind.  On the other hand, bombs don't blow people "off" the planet, they merely destroy them and leave their scattered remains.  With that in mind, my general question is this: when using the word literally, is it important that every word or phrase be meant to take on its most technically literal interpretation?  Or is it enough that there exist two, reasonable, alternative interpretations of the sentence, one of which is a more literal rendering, and that the more literal of the two is intended?


Is there a name for using a word twice in a row to express different levels of a similar thing?

There are a few phrases myself and others around me will use to change the meaning. The first example is “out”:     Shall we go out? — meaning “Shall we go to the pub?”   vs     Shall we go out out? — meaning “Shall we go to a club?”   And my second example is “home”:     “I’m going home later” — meaning “I’m going back to where I live when at university”   vs     “I’m going home home later” — meaning “I’m going back to where I live when not at uni, (probably my parents’).”   I’m curious if this usage of repeating a word to express different levels of the same thing has a name?  This question is different from  - here, there is no emphasis on the second word - in fact normally I think the emphasis is on the first word!


Minecraft crashing to launcher when joining server or loading singleplayer (Minecraft 1.7.9)

I've tried updating java, updating drivers and such and every time I press connect or load a server in Minecraft 1.7.9, it crashes back to the profile selector and launcher. Here's the error file:    It was too large to post here, so it's hosted there. If you have any idea what's wrong, let me know, all suggestions are appreciated, thanks!


US Citizen Departing on a non-US Passport

I am a US citizen holding multiple passports.  The problem is that my US passport is getting very full despite having 6 more years on it. There are Visas on my passport which I do not want to lose when I get a new passport.  I will be traveling to few countries and was thinking of using my non-US passport to exit the country.  My intent is to ration my US passport usage.  I also know a US Citizen must have US passport to enter and exit the country.  Entering is a "no duh".  Exiting.. well, we don't have exit checks in the US so I consider that a gray area.  see para (b)   Question 1.  Can I use this non US passport to exit the country?  Does the airline even care I as a US citizen am not using a passport to travel as long as the destinations are valid for entry with this non-US passport? This passport has no US visa on it to allow me to enter.  Therefore, I cannot enter or reside in the US with this passport.  The first leg of my trip includes a 1 day layover in Japan which I plant to exit the airport and walk around tokyo.  My non-US passport will allow me into Japan visa free.  The next leg is from Japan to Vietnam.  Vietnam requires a visa authorization letter (from both my passports) and then they will issue a visa on arrival (which takes up an entire page on my passport plus half a page for entry/exit stamps).  My intent is to obtain a visa authorization and arrival on this non-US passport.  Question 2:  When I check to my flight leaving the US.  Can I just show my non-US passport with the visa authorization for vietnam?  Or will I will I be rejected as I don't have an authorization for my US passport?  Alternatively, I was thinking of getting visa authorization letter for both passports. They are cheap. I can just show US passport at check in with visa authorization.  This will clear the airline to let me board.  when I arrive in Japan I can whip out my non US passport.  When I arrive in Vietnam I can whip out my non-US passport with the visa authorization letter.  this way I have avoided losing 2-3 pages in my US passport.  The next leg is to the country of my non-US passport.  This is inconsequential to my issues.  The final leg is back to the US and I will enter using US passport.  No stamps on entry.


So when I want to say "You can choose an apple and/or pear, and a bottle of soda and/or juice." Is there a better way to say this, without the clump of and/or?


hard self collision: make particles occupy space

By default, Blender's particles don't have any spatial extension. This is fine as long as particles are rendered as halos. But if you give them a size and an appearance as object, it becomes obvious that they're able to go through each other.  What tricks can be pulled off to fix that problem? For example, if you want to fill an area with houses, toss some leaves onto the floor, or just want charged balls to stick to each other.  I'm aware that a precise solution of this problem is very challenging -- but already some kind of approximation would do in most cases.


A badge that rewards "prophetic" downvoting

How about introducing a badge that rewards downvoting, but only of the sensible kind?   A measure for sensible downvoting would be a high percentage  certain number of downvotes on content that has subsequently been   Deleted  Closed (except migrations and duplicates)   Bronze, Silver, and Gold badges would vary in numbers, say     Bronze: cast 50 downvotes on content that was subsequently closed or deleted   This would encourage downvoting (which is great and needed), but of the measurably sensible kind only.  What  good actual numbers would be for Bronze, Silver, and Gold would be a separate discussion. Feel free to suggest numbers in your answers, as well as name suggestions (the only I managed to come up with was Whistleblowerand that isn't really accurate. I'm more imagining the old lady calling the council over some abandoned litter in the streets, or broken windows... but in a good way of course.


I am currently using XUbuntu 20.04, and I extracted my themes using  tar -xvf filename.tar.xz  my themes are now in the downloads folder but won't popup in my apperances.. I would like to add that I am a newbie to Linux. Thank you in advance for any help.


After using every, should it be singular or plural?

Is it correct to use: Not every student is as rude as you mentioned   Or  Not every student are as rude as you mentioned.  Thanks


Bug on Stack Exchange Mobile saving drafts

So I was asking a question on meta Arqade and when I saved my draft to go look at some questions and go back to my saved draft it merges all my tags together…  It turned   Into    Don't ask for the original question because I didn't post it.   This also happens on every stack exchange site.  Also, submitting the question with the weird tags brings up this...   If I try to submit it even if the required tags are met it says I need 500+ rep to create a new tag.  (App info)        App Version: 1.5.0.3   Device: iPhone 6   OS Version: Version 9.3.2 (Build 13F69)


Is IDENTITY continuous in new versions of PostgreSQL?

Now I am use serial to generate table primary key in PostgreSQL 13, but today I found the ID jumps and has big gaps in the ID space. It will waste many IDs. I read the docs and found that PostgreSQL has identity as a SQL standard generated primary key. I found a recommendation to use identity in new version of PostgreSQL but I don't know whether ID is continuous. What should I do get a primary key id without gaps in PostgreSQL 13?  Solution 1: I tried to change serial to identity like this: BEGIN; ALTER TABLE public.article ALTER id DROP DEFAULT; -- drop default  DROP SEQUENCE public.article_id_seq;              -- drop owned sequence  ALTER TABLE public.article  -- ALTER clientid SET DATA TYPE int,              -- not needed: already int    ALTER id ADD GENERATED ALWAYS AS IDENTITY (RESTART 2270886); COMMIT;  Still gaps. Solution 2: I tried to add a redis distribution lock about my apps insert article like this: def save_single(guid, pub_time, title, author, content, source, link):     if content is not None and len(content) > 0:         article = Article()         article_content = ArticleContent()         beta_parser = CnbetaParser()         second_parsed_content = beta_parser.parse_cnbeta_content(content, link)         article_content.article_content = second_parsed_content          cover_image = None         lock_identifier = None         try:                          # cover_image = Utils.get_cover_image_url(self, content, link)             lock_identifier = acquire_lock("article-save", 5, 5)             article.save(title, guid, author, pub_time, article_content, link, source, cover_image)         except Exception as e:             logger.error("save article data error,rss:" + source.sub_url, e)         finally:             if lock_identifier is not None:                 release_lock("article-save", lock_identifier)     else:         logger.error("article content is null,title:" + title)  Still gaps.


Is it acceptable to solicit money on a user profile?

I've just seen a user profile page which contains the following text:     Donations are welcome via Paypal. Paypal account is the same as my email address.   There's no context to suggest this has anything to do with supporting the user's favourite cause - it's a direct request for money.  Is this acceptable?


Not able to download anything from ubuntu terminal

I am new to Ubuntu and not well versed with its functioning.  I was trying to upgrade my git version and a few other things but I am constantly getting an error as shown in the image below due to some python3.6 minimal or python3.6.    My Ubuntu version is 14.04 and a few days back I tried to upgrade my python version from 2.7 to 3.6 but I believe I failed as when I type python -V in terminal, I am still getting 2.7.2 and on typing python3 -V, its showing 3.6.0.  I believe the problem is something related to multiple versions. Please help me out.


Why does current density have a direction and not current?

Current is a scalar $I$ with units of $\mathrm{[J/s]}$. It is defined as $I=\frac{\mathrm{d}Q}{\mathrm{d}t}$. Current density is a vector $\vec{J}$ (with magnitude $J$) with units of $\mathrm{[J/s/m^2]}$. It is current per unit cross-sectional area, and is defined as $\vec{J}=nq\vec{v_d}$ (where $n$ is the number of moving $q$-charges with drift velocity $v_d$).   Why is $I$ defined to not have a direction? Current density $\vec{J}$ is defined as a vector, so why is current $I$ not?  There are many questions about current vs. current density  ... like ,  and , but none answers my question about one being vector and the other being scalar. Is it simply just a definition? It just seems so obvious to define current as a vector too.    of current density is $I = \int \vec{J} \cdot d\vec{A}$. Mathematically, the dot product gives a scalar. But, for me this doesn't give much explanation still, as we could just as well have mathematically defined current as a vector and then used the area in scalar form in an equivalent formula like: $\vec I = \int \vec{J} \cdot dA$.  Is it just a definition without further reason, or is there a point in keeping $I$ in scalar form?


I am relatively new to the stock market and might not know all the useful terminology, so bear with me as I will do my best to explain what I am trying to grasp and hopefully I will be able to learn what's actually happening in this scenario. So let's say, a stock is trading at the price range from 1300 to 1400 on a specific day. Towards the end of the day, however not after close, you can see a mysterious dip in the price trendline of the stock - it is so sharp that it only is represented by a single price point, let's say at 400 for one time interval, and then it immediately goes back to the initial trading range. What happens there? Does it mean that someone was lucky enough to fulfill a limit buy at such a low price, and in such big volume that whoever was selling the stock at the market price had to fulfill it as it was the only volume being traded, at "the market" - and therefore the limit buy had to be honoured? I am at my wits here, especially since I dont know the name of it I am unable to find an image to attach, however I have often noticed it with TSLA, when there is literally a split second, enormous dip in the stock price for it to only go back to the same range it was trading before that. If I see it next time I will definitely add it onto the post.


Rotating only one feature of a point layer

I am working on a gas network utility and I create some point layers in order to insert some symbols of special forms. However, each symbol should be attached the network with a specific angle in order to fit it with the network. Rotating actions applies to all point symbols of the layer. Is it possible to rotate only one feature?


Remove whitespace only between two characters { and } in file

I have file with json values :  abc={"adf": "def",   "abc2":"def2", "abc3" : "def3" } abc4= 1 abc = {hello : world, hello:"a"}   I want to remove whitespace from everywhere in between  { and } and not any other place. Values don't have any spaces in my case.  abc={"adf":"def","abc2":"def2","abc3":"def3"} abc4= 1 abc = {hello:world,hello:"a"}   How can i use sed, awk or perl or any tool to achieve this ?  Note: All values are in one line only. There is no multi line processing required.


I am trying to edit elements in my list of list of list but it is editing multiple elements.       L1 = [[0,0] for count in range(2)]     L2 = [L1 for count in range(2)]     L2[0][0][0] = 5     print(L2)   What I expect is [[[5, 0], [0, 0]], [[0, 0], [0, 0]]]  But what I get is [[[5, 0], [0, 0]], [[5, 0], [0, 0]]]  It seems that I am editing the original list. Can someone explain how to edit a single element or set up nested lists where this effect won't occur.  Many thanks


Is there anybody, who is able to install and fully configure Ubuntu 12.04 or 14.04 on Thinkpad T440p (ver 20AN)? If yes, could you post here your procedure step by step?  Please does not include your experience with any other ThinkPad models.  Edit: Situation is not so simple, see:


Why pick a NAS over a "normal" NFS share?

From an end-user perspective, what is the difference between a NAS device and using NFS exports from a file server?  They seem to accomplish the same end result.  The difference between a SAN and other file storage is related (in my experience) to how they are connected to the server infrastructure.  However, the difference between a NAS, connecting over a standard ethernet port, and NFS (sharing storage off specific servers, also over the network), seems more nebulous.  Is there a good reason to pick a NAS filer over just running NFS on servers?


Is friction a function of surface area? What is the microscopic workings of friction?

I know the friction is given by the following equation $$\mu F_N=F_f$$  which tells me friction is independent of surface area, but how do I characterize it as such if I want to add surface area into my equation what would the equation be?  We all know friction is a function of the normal reaction exerted on the body and the coefficient of friction. How is this coefficient derived, any equation? Or is it all experimental? Any quantum mechanical explanation for friction?


Why can't the end code of an environment contain an argument?

Environments are allowed to have arguments, but reference to those arguments can only appear in the opening code of the environment, and not the closing code.  What is the reason for this, and are there preferred ways around it?  e.g.  \newenvironment{foo}[1]% {some code #1} % allowed {some code #1} % not allowed


(grub rescue prompt while booting from a live usb)How to get rid of GRUB and Install another OS?

I am running a dual boot setup of windows and Ubuntu and I wanted to install Manjaro KDE Chain of events that lead me into this mess 1.To get rid of Ubuntu I deleted it's partition and now I am stuck with grub rescue prompt "directory not found" 2.To get rid of grub rescue I followed the steps in this  involving the removal of ubuntu folder in the EFI directory 3.Achivement: got rid of grub rescue 4.Now to install the OS I wanted to try(Manjaro) I made a bootable live usb using , plugged it and tried to boot from it and again guess what! grub rescue 5.just to make sure there is no problem with the live USB, I made a bootable USB of Ubuntu to check 6.geuss what it worked fine and I was able to install Ubuntu but if I plug in any another OS other than Ubuntu grub rescue shows up unknown file system only a live usb with ubuntu is able to boot and any other usb with other os prompts grub rescue help!!! I really want to get rid of grub rescue and try manjaro


Is there any way in which I can either hide the 5.1 and 5.1.1? So I can directly use what I set to the right I would need to do this hiding only for specific subsections /subsubsections


How to know information about how many resources does given process consume in C++?

Do any commands or extension in C++ exist to find out how much CPU time, operative memory, network resources and hard-disk does a given process (with given PID) consume?


How to prevent iMessage syncing without access to device

I foolishly logged into someone's iPad with my Apple ID. This person is now receiving my full communications on iMessage. I know I can remove my account from that iPad but I don't have access to it. How can I stop the device from getting my iMessages without physical access?


I have this problem,  Let $$p_n(x)=nx^{n+1}-(n+1)x^n+1 \in \mathbb Q[x]$$ for any positive integer $n$. Show that there exist a polynomial $q_n(x) \in \mathbb Q[x] $ satisfying $p_n(x)=(x-1)^2q_n(x)$.  initially I thought that I could use the division algorithm, such that $p_n(x)=(x-1)^2q_n(x)+v(x)$ but is there a reason that we could say that $v(x)=0$?


How do I know there are only 5 different groups of order 8?

How many different groups are there in order 8? And how do I know which groups they are? I mean, is there anyone can teach me to calculate them? I want a proof, thank you!  They are $C_8$, $D_4$, $Q_8$, $C_{4h}=C_4 \times V_2$, $D_{2h}=D_2 \times V_2$


When is $x^{\alpha}\sin(x^{\beta})$ uniformly continuous for $\alpha, \beta > 0$?

Consider a function $f_{\alpha, \beta}\colon (0, \infty) \longrightarrow \mathbb{R}$ defined in the following way:  $$f_{\alpha, \beta} = x^{\alpha}\sin(x^{\beta}) \quad \alpha, \beta > 0$$  Then we can pose the questions:    For which pairs $\alpha, \beta$ is this function uniformly continuous? For which sets $(\alpha, \beta)$ in $(0, \infty)^2$ is the family equicontinuous?   I am baffled as to how to go about answering these questions in a clear and concise way. I think that it is possible to produce an answer by considering many cases and lots of tedious estimates. Is there a better way to approach the problem?  Any help will be appreciated.


Can't extend root partition using gparted

I'm new to Ubuntu. I've allocated 110 GB to my root partition and I have 315 GB unallocated space and I'm trying to extend my root partition to include the excess 315 GB. I have searched for other methods but i can't understand the process because I have missing partitions like linux-swap and the extend partition.    And also i tried unlocking my ext4 partition but it said      currently in use disk is busy   How can I extend my root partition to use the unallocated space to its left?


Given fields $M/E/F$, why does $[M:F] = [M:E][E:F]$?

Let $M$ be a finite extension of $E$ and let $E$ be a finite extension of $F$. Then $M$ is a finite extension of $F$ and $[M:F] = [M:E][E:F]$.   Is there an easy explanation and/or proof for this theorem? My instructor gave an incomplete proof in class but got stuck and I'm kind of confused of what's going on.


Is there any benefit to this switch / pattern matching idea?

I've been looking at F# recently, and while I'm not likely to leap the fence any time soon, it definitely highlights some areas where C# (or library support) could make life easier.  In particular, I'm thinking about the pattern matching capability of F#, which allows a very rich syntax - much more expressive than the current switch/conditional C# equivalents. I won't try to give a direct example (my F# isn't up to it), but in short it allows:   match by type (with full-coverage checking for discriminated unions) [note this also infers the type for the bound variable, giving member access etc] match by predicate combinations of the above (and possibly some other scenarios I'm not aware of)   While it would be lovely for C# to eventually borrow [ahem] some of this richness, in the interim I've been looking at what can be done at runtime - for example, it is fairly easy to knock together some objects to allow:  var getRentPrice = new Switch<Vehicle, int>()         .Case<Motorcycle>(bike => 100 + bike.Cylinders * 10) // "bike" here is typed as Motorcycle         .Case<Bicycle>(30) // returns a constant         .Case<Car>(car => car.EngineType == EngineType.Diesel, car => 220 + car.Doors * 20)         .Case<Car>(car => car.EngineType == EngineType.Gasoline, car => 200 + car.Doors * 20)         .ElseThrow(); // or could use a Default(...) terminator   where getRentPrice is a Func<Vehicle,int>.  [note - maybe Switch/Case here is the wrong terms... but it shows the idea]  To me, this is a lot clearer than the equivalent using repeated if/else, or a composite ternary conditional (which gets very messy for non-trivial expressions - brackets galore). It also avoids a lot of casting, and allows for simple extension (either directly or via extension methods) to more-specific matches, for example an InRange(...) match comparable to the VB Select...Case "x To y" usage.  I'm just trying to gauge if people think there is much benefit from constructs like the above (in the absence of language support)?  Note additionally that I've been playing with 3 variants of the above:   a Func<TSource,TValue> version for evaluation - comparable to composite ternary conditional statements an Action<TSource> version - comparable to if/else if/else if/else if/else an Expression<Func<TSource,TValue>> version - as the first, but usable by arbitrary LINQ providers   Additionally, using the Expression-based version enables Expression-tree re-writing, essentially inlining all the branches into a single composite conditional Expression, rather than using repeated invocation. I haven't checked recently, but in some early Entity Framework builds I seem to recall this being necessary, as it didn't like InvocationExpression very much. It also allows more efficient usage with LINQ-to-Objects, since it avoids repeated delegate invocations - tests show a match like the above (using the Expression form) performing at the same speed [marginally quicker, in fact] compared to the equivalent C# composite conditional statement. For completeness, the Func<...> based-version took 4 times as long as the C# conditional statement, but is still very quick and is unlikely to be a major bottleneck in most use-cases.  I welcome any thoughts / input / critique / etc on the above (or on the possibilities of richer C# language support... here's hoping ;-p).


What (if any) is the proper hyphenation for the phrase "it's all too easy"?

Are any of the following correct?     It's all too-easy   It's all-too-easy   It's all too easy   Explanation/citations would be greatly appreciated


Is there a way to manage document permissions by code.  i.e., inside a .tex file, insert a command to restrict document only to view and printing?


Summon Greater Demon: Can I summon a specific demon for which I know the true name?

The Summon Greater Demon spell is especially effective when the summoned demon's true name is known:  At the end of each of the demon’s turns, it makes a Charisma saving throw. The demon has disadvantage on this saving throw if you say its true name.  However, the spell description doesn't say that it is possible to request a specific demon for which the true name is known:  You utter foul words, summoning one demon from the chaos of the Abyss. You choose the demon’s type, which must be one of challenge rating 5 or lower, such as a shadow demon or a barlgura.  Is it possible to request a demon for which the true name is known?


For a given condition is it true that $a+b+c=3$.

Suppose a, b, c  are positive real numbers such that    $$(1+a+b+c)\left(1+\frac 1a+\frac 1b+\frac 1c\right)=16$$  Then is it true that  we must have  $a+b+c=3$ ?  Please help me to solve this. Thanks in advance.


Minecraft Bow Command ./give multiple enchants

So I have this one command creation that I want to use. And I am not sure about the syntax. I want to put multiple enchants on my bow. Can you guys  help me with my command so that it works?  Here is my command:  /.give @p minecraft:bow 1 0 {display:{Lore:[Forged by Dark_Matrix9]}, Unbreakable:1ench:[{id:48,lvl:10000,id:49,lvl:10000,id:50,lvl:10000,id:51,lvl:10000]}   How do I connect the enchants?


If $xy$ divides $x^2 + y^2$ show that $x=\pm y$

Problem statement : Let $x,y$ be integers, show that if $xy$ divides $x^2 + y^2$ then $x=\pm y.$  What I have tried:   I can reduce this to the case where $\gcd(x,y)=1$, since if $x$ and $y$ have a common factor, $d$ say, then $d^2$  divides through both $xy$ and  $x^2 + y^2$   This then allows me to introduce another equation $1=ax+by$ for some $a, b.$  But I then get stuck ...


I'm learning SDL 2.0 at the moment and I've seen this method for loading BMPs:  SDL_Texture* LoadImage(std::string file) {     SDL_Surface *loadedImage = nullptr;     SDL_Texture *texture = nullptr;     loadedImage = SDL_LoadBMP(file.c_str());      if (loadedImage != nullptr)     {         texture = SDL_CreateTextureFromSurface(renderer, loadedImage);         SDL_FreeSurface(loadedImage);     }      else         std::cout << SDL_GetError() << std::endl;         return texture; }   How could I switch it up to load PNG files?  EDIT: Woops, forgot to add my method of loading PNGs.  SDL_Texture* grass_image = nullptr; grass_image = IMG_LoadTexture(renderer, "res/grass.bmp"); SDL_Rect grass_rect;     grass_rect.x = 0;     grass_rect.y = 0;     grass_rect.w = SCREEN_WIDTH;     grass_rect.h = SCREEN_HEIGHT;  if (grass_image == NULL)     std::cout << "Couldn't load grass_image" << std::endl;  while (!quit && mainEvent -> type != SDL_Quit) {     SDL_RenderCopy(renderer, grass_image, NULL, &grass_rect); }   I just don't want to have to do that for EVERY image.  So how could I put that into a function?  Thanks!


Can or Could - which one is correct to usein question

Can you please shift a little? or Could you please shift a little?   which one of the two is correct?


Mouse clicklock needed for accessibility! Where is it?

Here's a news article:   I have a disability and I really need this feature to fully use the computer.   I've heard rumors that it used to be included in an old distro (I've tried 14.04 and 8.04, not there). Does anyone know how to get it back or how to implement it? I think it might be in xorg …


Understanding cross entropy in neural networks

provides a nice explanation and derivation of cross entropy, and defines it as follows:  $H(y, \hat{y}) = -\sum_i[ y_i \log \hat{y}_i]$         ....... (1)  where $y$ is the correct output and $\hat{y}$ is the network's predicted output.  Many  use this definition of cross entropy:  $Loss = -\sum_i[ y_i \log \hat{y}_i + (1-y_i) \log(1- \hat{y}_i))]$         ....... (2)  These equations are different, where does equation 2 come from? Is equation 2 a better loss function for neural networks?


Since LaTeX can produce outstanding typesetting results and excellent graphics design, I began to wonder if it can recreate certificates. With so many packages and styles out there does anyone know if there is one to create certificate templates like the following example.    I suppose that the borders would be the limiting factor like those shown .


I want to cut an array column in a CSV file. For example if you see the below CSV file  input.csv  1,2,"{1,2,3}",1  3,4,"{3,9,1}",2  8,9,"{10,12,30}",3   I want the output as   output.csv  1,2,3  3,9,1  10,12,30   I tried using cut -d , -f 3 input.csv and cut -d { -f 3 input.csv but both did not work .Any help is appreciated.Thanks in advance.


Hello I have a Dualboot system with Windows 10 and Ubuntu 20.04 and I use Ubuntu grub so the grub is like this:-                                         Grub [Its version] 1) Ubuntu 2) Advanced option for Ubuntu  3) Windows boot loader 4) UEFI Configuration  So I want to change it to this :- is it possible?                                             Grub [Its Version] 1) Windows Boot Loader 2) Ubuntu  3) Advanced option for Ubuntu 4) UEFI Configuration  And also after updates the grub is updated everytime so will it revert it to the previous even if I changed it? Thankyou.


Number of certain (0,1)-matrices, Stanley's Enumerative Combinatorics

Stanley's Enumerative Combinatorics () contains next fact: 1.1.3 Example. Let f(n) be the number of n × n matrices M of $0$’s and $1$’s such that every row and column of M has three 1’s. For example, f(0) = 1, f(1) = f(2) = 0, f(3) = 1. The most explicit formula known at present for f(n) is $$f(n)=6^{-n}{(n!)}^2\sum\frac{(-1)^{\beta}(\beta+3\gamma)!2^\alpha 3^{\beta}}{\alpha!\beta!\gamma!^26^{\gamma}}$$ where the sum ranges over all (n + 2)(n + 1)/2 solutions to α + β + γ = n in nonnegative integers.   I need proof of this fact. (i.e. reference to book or articles that contains proof this fact).


How to sort a HashMap with DateTime object

I want to sort a HashMap of timestamps .  Here is my timestamps hashmap.  Map<String, DateTime> timestamps = new HashMap<> ();   I dont know which method i should use to sort this type of hashmaps . So I cant provide any additional code.   Thank you for ur help !


Where is the HM "Rock Smash" in Pokemon Omega Ruby/Alpha Sapphire (oras)?

I've been running around Mauville, Verdandorf and Slateport for a long time and I still can't find rock smash. I'm at the point where there is a girl standing in a cave in front of rocks and says you need rock smadh to pass. I have 3 badges already. PLEASE HELP! 0_0


How to transfer app settings from Galaxy S3 to a S6 without root?

After trying to manually set the "app settings" on my new S6 the same as my S3: I realize it will take me hours.  Is there really no way to transfer all old app settings from my S3 to the newly installed apps of my S6?  Helium needs a PC and others need root on both phones.  Any suggestions?


Replace HTML page with contents retrieved via AJAX

I have an HTML page with a typical structure:  <html>   <head>    <script src="..." ></script>    <style>...</style>   </head>   <body>    content   </body>   <script>     var success_callback = function(data) {       // REPLACE PAGE CONTENT & STRUCTURE WITH "data"     }     ajax(url, params, success_callback);   </script> </html>   Do you think it is possible ?  I've already tried to give the html tag an id and doing $(id).replace(data); with no success.  Don't ask me why, but that is what I need (I'm working with a special "mashup builder" site... it is a long story).  EDIT : I forgot to say that scripts in the received content have to be executed, even external scripts included using <script src="...">.


I want to display an output in my HTML text area using Javascript, but I cannot figure out how to insert the line breaks. Based on other answers I found here, I tried this:  txtResults.value = "Route: " + route + "\\\n" + "Start Station: " + stnStart + "\\\n" + "End Station: " + stnEnd;   but the output comes out as  Route: A>B>C \ Start Station: A\ End Station: C   but if instead of \\\n I put \\n the output comes out as  Route: A>B>C \nStart Station: A\nEnd Station: C   how do I make it like as follows?  Route: A>B>C Start Station: A End Station: C


This is a number theory exercise I've been stuck on for a while. It was set during a lecture I attended once. It goes something like this . . .  Suppose there's a full circular prison with 100 cells and one prison guard who hates his job. He gets drunk one night and decides to play a game while the prisoners were asleep. He walks the circular prison and, the first time, he opens every cell; the second time, he closes every even numbered cell; the third time, he touches every third cell, and if that cell is open, he closes it, and he opens it otherwise; the fourth time, he touches every fourth cell, and if that cell is open, he closes it, and he opens it otherwise; and so on until his hundredth time around the prison. He then falls asleep. By the morning, after the prison guard's hundredth lap, every prisoner in an open cell escapes. Which prisoners escape?  Thoughts: I've thought of trying a modified use of the Sieve of Eratosthenes but there's got to be a more elegant, less brute-force solution.


Can Microsoft Office 365 be installed on Ubuntu 16.04? if it can be installed, how is it done?  I appreciate any help I can get on this.


beamer+biblatex: change the \footnotemark style of \footcite

Is it possible to change the \footnotemark style created by \footcite (from biblatex) so that it looks more like a citation symbol?    I want to keep my references as footnotes, but I would like them to look more like actual citations.  MWE:  % arara: pdflatex % arara: bibtex % arara: pdflatex % arara: pdflatex % arara: clean: {files:[temp.aux, temp.bbl, temp.bib, temp.blg, temp.log, temp.nav, temp.out, temp.run.xml, temp.snm, temp.toc, temp-blx.bib]}  \documentclass{beamer}  \usepackage{filecontents} \begin{filecontents}{\jobname.bib} @article{greenwade93,     author  = "George D. Greenwade",     title   = "The {C}omprehensive {T}ex {A}rchive {N}etwork ({CTAN})",     year    = "1993",     journal = "TUGBoat",     volume  = "14",     number  = "3",     pages   = "342--351" } @book{goossens93,     author    = "Michel Goossens and Frank Mittelbach and Alexander Samarin",     title     = "The LaTeX Companion",     year      = "1993",     publisher = "Addison-Wesley",     address   = "Reading, Massachusetts" } \end{filecontents}  \usepackage[english]{babel} \usepackage[backend=bibtex, style=verbose]{biblatex} \addbibresource{\jobname}  \begin{document}  \begin{frame} Bla bla bla \footcite{greenwade93} Ble ble ble \footcite{goossens93} \end{frame}  \end{document}   NOTE 1: There are many questions on tex.stackexchange.com about changing the style of the footnote style. This is about the footnotemark itself.  NOTE 2: I don't use footnotes for anything else, so I don't mind changing the footnotemark directly, ignoring whether it was created by footcite or not. I just could not find how to customize footnotemarks this way...


Is there any difference on the use of I'm and I am?

Is it correct to write I am Gerardo and I am here.  or I am Gerardo and I'm here. Is there any difference between these two statements?


This question is related to . The below query was taking 10 to 15 seconds to execute:  SELECT [customer].[Customer name],[customer].[Sl_No],[customer].[Id] FROM [company].dbo.[customer] WHERE (Charindex('123456789',CAST([company].dbo.[customer].[Phone no] AS VARCHAR(MAX)))>0)    In some articles I saw that using CAST and CHARINDEX will not benefit from indexing. There are also some articles that say using LIKE '%abc%' will not benefit from indexing while LIKE 'abc%' will:      In my case I can rewrite the query as:  SELECT [customer].[Customer name],[customer].[Sl_No],[customer].[Id] FROM [company].dbo.[customer] WHERE [company].dbo.[customer].[Phone no]  LIKE '%123456789%'   This query gives the same output as the previous one. I have created a nonclustered index for column Phone no. When I execute this query it runs in just 1 second. This is a huge change compared with 14 seconds previously.  How does LIKE '%123456789%' benefit from indexing?  Why do the listed articles state that it will not improve performance?  I tried rewriting the query to use CHARINDEX, but performance is still slow. Why does CHARINDEX not benefit from the indexing as it appears the LIKE query does?  Query using CHARINDEX:  SELECT [customer].[Customer name],[customer].[Sl_No],[customer].[Id]  FROM [Company].dbo.[customer]  WHERE ( Charindex('9000413237',[Company].dbo.[customer].[Phone no])>0 )    Execution plan:    Query using LIKE:  SELECT [customer].[Customer name],[customer].[Sl_No],[customer].[Id]  FROM [Company].dbo.[customer]  WHERE[Company].dbo.[customer].[Phone no] LIKE '%9000413237%'   Execution plan:


Finding $\int_{0}^{\frac{\pi}{4}} \frac{\tan \theta - \tan^3 \theta}{\ln \tan \theta}$

The original question was to evaluate:   $$\int_{0}^{1} \frac{1-x}{(1+x) \ln x}\,dx$$  Using the substitution $x=\tan^2 \theta $, I simplified it down to the integral $\int_{0}^{\frac{\pi}{4}} \frac{\tan \theta - \tan^3 \theta}{\ln \tan \theta}$.  From here, I am stuck and am not sure where to continue.


We can know clearly from  $$(1+X)^n=\sum\limits_{i=0}^{n}C(n,i)X^n$$ that $$ \sum\limits_{i=0}^{n}C(n,i)=2^n.$$  Whereas, I want to know if there are any researched results about permutations in the similar case, i.e., what can we know about  $$ \sum\limits_{i=0}^{n}P(n,i).$$  I’m really curious about that, but have found no answers elsewhere. Any help will be sincerely appreciated!


The naturality of the canonical projections?

The first isomorphism theorem (for groups) states that $G/ \text{Ker} (\varphi) = \varphi(G)$. This is called the canonical projection, but also sometimes the natural projection. I wondered if this is because these canonical projections were actually natural transformation between appropriate functors.


What gets trigged fist List Workflow item added or List Event Receiver ItemAdded.?

Workflow Vs Event Receiver I have a list in a site collection called projects. I have a workflow on Item Added and now currently in the process of creating Event Receiver.  I would like to know which actually gets trigged first. Event Receiver or Workflow?  Thanks..


An example of grey and white note that I mean is, like when you copy something, a small grey background and white lettered bubble appears for a few moments saying 'copied to clipboard'. My phone has some sort of malfunction where it dispays that prompt for several minutes at a time. Very annoying. How do I disable that? I am using a Samsung Galaxy S9.