Where should I ask questions about ESP8266?

I tried asking general high level (newb-ish) questions about the ESP8266's firmware, how it works, Arduino IDE, sketches in general at Arduino Stack Exchange but was told it was off-topic. I think the IoT site doesn't seem like the right place either and Arduino Stack Exchange seemed like the most relevant to me. Which site should I post this question?  Does flashing ESP8266/ESP-01 firmware mean uploading a new 'sketch' and why different firmware? Hi, I am new to IoT and I am now in love with this. However I'm a little confused right now with the jargon. My question is similar to . But I do have some extra questions though.  When using ESP as standalone microcontroller, and if I uploaded a sketch written on the Arduino IDE, does that count as 'Arduino firmware' other people are referring to?  On the Arduino IDE, uploading sketches onto the ESP8266 seems easy by just installing extra libraries from Board Manager and selecting the right board. Is this step equivalent of doing this but for different firmwares such as AT, NodeMCU and Micropython?  For the NodeMCU dev boards, is the default firmware on the module NodeMCU firmware? If I were to use the Arduino IDE to upload a sketch, does that mean I have overwritten the NodeMCU firmware with my custom 'Arduino firmware' sketch?  To the extent of my knowledge, when using NodeMCU firmware, I would need to code in LUA language using some sort of LUA IDE and if I flashed/uploaded micropython I would need to code in micropython using exclusively the Thonny IDE. And there is no way to code in micropy or LUA from the Arduino IDE.  Is the reason for using other firmware is because of how the code is compiled and the language used?


If $n\geq m$ show that: $(x^m+y^m)^{1/m} \ge (x^n+y^n)^{1/n}$, all numbers being positive real.   Obviously since $n\geq m$, for every $a\in \Bbb Z^+$: $a^{1/m}\geq a^{1/n}$, but does it help?


What is the meaning difference in below sentences?  a) Police are yet to arrest anyone for murder.  b) Police have yet to arrest anyone for murder.  according to me Sentence a) gives status of the case and sentence b) gives Idea that police have not completed the action of arresting till date.


Unable to install firefox 27 on ubuntu 12.04

I am trying to install firefox 27 through canonical repos but it shows firefox 26 as the latest version. How do i install firefox 27 on ubuntu 12.04?


Why are there so few posts with zero comments?

While researching my theory that , I noticed that there are surprisingly few posts with zero comments.  Here's what the  looks like:  That graph was generated using the following SQL: select CommentCount, count(*)  from Posts  where CommentCount < 30 group by CommentCount order by CommentCount  The huge distribution disconnect makes me think comments are not being counted correctly.


Why can't two methods be declared with the same signature even though their return types are different?

Duplicate:     Maybe this is a very silly question but I don't understand why I can't declare two methods that have the same signature when they have different return types.  public class MyClass {     private double d = 0;      public double MyMethod()     {         return d;     }      public string MyMethod()     {         return d.ToString();     } }   I get a compile error that states that the class already defines a member with the same parameter types.  (Obviously the way I'm using this in my code isn't as simple as my example code...but I think it gets the idea across.)  Am I missing something concerning OO design that makes what I'm trying to do an OOP anti-pattern? Surely the compiler should be able to determine which method I'm trying to use as long as I specifically tell it which one I want.  Given MyClass myClass = new MyClass(); I would expect the following code to work:  double d = myClass.MyMethod(); string s = myClass.MyMethod();   I would expect the following code to have problems:  var v = myClass.MyMethod();   But even in the case of var it should result in a compile error.  Can anyone see what I'm doing wrong here? I'm more than happy to be corrected. :-)


Let $Z$ be a closed set in a quasi projective variety $X$.  My question is what can we say about $Z$ if $\dim Z=0?$  I know $\dim Z=0$ implies all irreducible components of $Z$ is zero-dimensional.


Having no friends or not having friends.   Are they equal or different?  I think they are in same format with these two sentences being equal. Do you not like him? or Don't you like him?


Why does water not spill out of a cup when the cup is upside down on a smooth surface?

Note: This is for a physics project, so please don't just give me the answer...   Say we have a cup that is 3/4 full with water. We place that cup (with the water in it) upside down on a smooth table. Why doesn't the water fall out?  This is my understanding... The cup on the table has created an air tight seal that does not allow water to leak out nor any air to enter the cup. Also, as water gets deeper, the pressure increases. Therefore, there is a greater force of water pushing down on the table which the cup contains. But, wouldn't this cause the water to escape the cup? Also, there would be an area of low pressure in the "top" of the cup, but I'm unsure how that has anything to do with the water not escaping the cup...  Any insight would be great!


Polynomials and Arithmetic: If $p(x_i) = 7$ for four integers, then $p(z)\ne14$

Consider the polynomial $$p(x) = a_0 + a_1x + a_2x^2 + · · · + a_nx^n$$ where $a_0, a_1, . . . , a_n ∈ \Bbb Z$. Show that if $p(x_i) = 7$ for 4 distinct integers $x_0, x_1, x_2, x_3$, then $p(z) \neq 14$ for any $z ∈ \Bbb Z$.    How do I start this question?


Why are there changes in location when printing inserted points?

Añadí una capa de texto delimitado por comas y luego agregue una imagen satelital de google earth. Realizo un diseño de impresión y al imprimir cambia la ubicación de los puntos en varios metros. Cual es la solucion?  (Edit) Google Translation:  I added a layer of comma delimited text then added a satellite image from Google Earth. I do a print design and during printing the locations of the points change by several meters.  What is the solution?


How to free space on VirtualBox Debian VM

I have a Debian Jessie VM in VirtualBox that I use for C++ programming. The primary virtual disk is set to be dynamically allocated 32GB. Over time, I have gradually used more space on the virtual disk, but recently I cleared my Bazel cache and removed other extraneous files.  Running df -h on the VM yields:  Filesystem Size Used Avail Use% Mounted on  /dev/sda1 31G 14G 15G 48% /  udev 10M 0 10M 0% /dev  tmpfs 403M 5.9M 397M 2% /run  tmpfs 1006M 68K 1006M 1% /dev/shm  tmpfs 5.0M 4.0K 5.0M 1% /run/lock  tmpfs 1006M 0 1006M 0% /sys/fs/cgroup  tmpfs 202M 4.0K 202M 1% /run/user/117  tmpfs 202M 8.0K 202M 1% /run/user/1000   From the command output, it appears as if I have only 14GB of space used on the virtual disk, but the VDI file still has a size of 24.2GB. Is there any way to shrink the VDI to the current size of the virtual disk?  EDIT: I have looked at the tools that were recommended by the other questions. None of them work for me, as I cannot figure out how to make zerofree run on my system and sfill -fvz (from secure-delete) only makes VirtualBox think the VM uses all of the 32 GB virtual disk. I don't know where to go from here.  Thanks, Neil


How to prove the divisibility rule for $3\, $ [casting out threes]

The divisibility rule for $3$ is well-known: if you add up the digits of $n$ and the sum is divisible by $3$, then $n$ is divisible by three.  This is quite helpful for determining if really large numbers are multiples of three, because we can recursively apply this rule:  $$1212582439 \rightarrow 37 \rightarrow 10\rightarrow 1 \implies 3\not\mid 1212582439$$ $$124524 \rightarrow 18 \rightarrow 9 \implies 3\mid 124524$$  This works for as many numbers as I've tried.  However, I'm not sure how this may be proven.  Thus, my question is:     Given a positive integer $n$ and that $3\mid\text{(the sum of the digits of $n$)}$, how may we prove that $3\mid n$?


What book had a character who could control magical strands or streams?

I am looking for a title of a book, The main character could send out a "strand, stream?" of magic to retrieve whatever he wished.  If he wanted a beer he would get it and one would disappear elsewhere in the world. I know I read the book as a paperback, maybe in the mid to late 90's.


An image of the web page:  I want to put the button in the middle of the first box. I have followed a  from w3 schools  but it puts the button in the middle of webpage instead of putting it in the middle of the first box. My code:   .menus{     display: flex;     justify-content: space-evenly; }  .menu{     background-color: orange;     border: 3px solid grey;     width: 98vh;     height: 98vh; }  .menu1{     min-height: 50px; }  .menu2{     min-height: 50px; }  .menu1 h1{     magin-top: 50px;     text-align: center; }

                     <button>button</button>


My teacher said that the force is mass times acceleration. But, how are mass and acceleration related to force?


How does SSL certificate effect Google Indexing Ranking?

I have Bought 2 SSL certificate one Basic and One Premium   The basic one will just give me https://example.com  The Premium will also giving me https and a Greebar in URL displaying the Company Name  Will implementing SSL would make any difference to my Google SEO ranking? And will the result be any different if By Implementing the premium one rather than the basic one


Remove junk applications from new computer en masse with tracking

How do I remove those pesky junk programs typically associated with a new computer? Going through Add/Remove Programs in the control panel seems very slow as it is only allowing me to uninstall one thing at a time.  I want to speed up this process, is there an application for massively uninstalling applications?   If so, does it have an internal database that can tell you what an application is for and any complications caused by uninstalling it?


Can a spellcaster use spell slots above their normal limit if their ability scores allow bonus spells of that level?

This question is inspired by discussion , about how Heighten Spell works with Reserve Feats.  The question that I am asking here deals with whether or not players can cast spells using spell slots for spell levels that they don't have access to yet.    I feel like an example would explain this concept best.  Take Xylitol, the first-level wizard with an intelligence of 18.  He has 5 0th-level spells per day and 3 1st level spells per day from his class.  He also has 1 bonus 1st level spell per day from his high intelligence.  The  table says that he also has 1 bonus spell of each 2nd, 3rd, and 4th levels.  The question is this:  Can Xylitol cast 1st level spells using the bonus slots for his 2nd, 3rd, and 4th level spells?  He clearly can't cast spells that are inherently higher level than 1st, since he can't learn them, but can he cast 1st level spells using bonus 2nd, 3rd, and 4th level slots?  This has come up on these boards before, .  What I'm looking for here is a clear rules citation that clarifies this one way or the other.  The wording in the section on ability scores makes it quite clear that characters cannot cast spells that are actually higher level than their class allows them to cast, but it is not clear that these higher level slots are barred until the appropriate spell level is unlocked.  If a character has access to a spell level that they can't use because their ability score isn't high enough, they can freely use those slots for lower level spells, so why can't they use their bonus spell slots for lower level spells?  As KRyan's answer says, the Basics section covers this.  Based on questions and comments both here and elsewhere, that section seems to be worded ambiguously enough that it's caused confusion.  I'd like to find another, more clear wording to this rule if at all possible.  Answers from either D&D 3.5 or Pathfinder are acceptable, but please note which one your answer applies to.  N.B. I'd like to note that I personally don't feel that players should have access to higher level slots like this.  There are a large number of locations where it's heavily implied that this is not the case, but I feel that finding a clear rules citation here would be helpful.  I can't find one that is clear for either interpretation here.


Would approaching a distant star at near the speed of light unfold its entire history in "fast-forward"?

The light we detect today in our telescopes from distant stars is really old.  If we could travel fast (lets say, 90% the speed of light) towards a star a million lightyears away, all the time looking straight at it, would we see that star's entire history unfolds in fast-forward ▶▶ until we reach it? (if it's still there, of course).   It seems reasonable that "newer" photons emitted from that star would hit our eyes at a faster rate while we approach it.  Thanks.


INSERTING MULTIPLE RECORDS USING SALESFORCE REST API

i need to insert multiple records from one org to another org using rest API(bulk) am unable to insert multiple records ..as of now am able to insert single record successfully.can you please tell how to do this ..


Solution for PHP / MySQL website loading fast in multiple regions

I host am ExpressionEngine based website on a single Amazon EC2 instance in the US East (Virginia) region. I use Ubuntu.    The website allows members to post their content, and displays it for other members and for users who are not logged in.   Goal: I need to begin serving the same website across the globe, equally fast to Hong Kong, New York, and Los Angeles.   I considered two solutions:  1.Setting up three separate EC2 instances for three regions: Virginia, Oregon, and Singapore. Use Amazon Rot53 Geo Location to direct traffic to instances based on the browser's IP address.   Pro: the website will load fast for the region.   Contra: these will be essentially three separate websites. Unless I am mistaken?   Setting up one instance in a region equally remote from all three locations: (Ireliand), and boost the server to the highest performance available.    Pro: It will be the same website for all regions.   Contra: it will cost a lot to make it fast enough.   My challenges:   a) I do not know a way to sync server settings, database, and content between multiple Ubuntu instances in real time. If a knowledgeable person could explain to me how to do that, I would be most grateful.   b) I am not thoroughly familiar with all Amazon AWS resources. Does AWS has a built-in method that would allow me to achieve my goal of serving a single PHP / MySQL based membership website across the globe equally fast in all three chosen locations?


total newbie please help with installing the ISO

I have been a Windows user all my life but want to move to Linux.  I have downloaded the ISO file for Ubuntu Late..now what?  please help  thanks alot   Craig


BAC  GM  IBM  TRW       JOHN   200 300  100  200 A =       PAUL   100 200  400    0   I would like to create an array that looks like what appears above, except that square brackets should enclose (only) the array of numbers, whose rows and columns should nonetheless be aligned with the things set in letters.  The "A" should not be aligned with a blank middle row of the array of numbers, but rather, centered as if one had written this:  A = \left[ \begin{array}{cccc} .... \end{array} \right]   How can that be done?


Are collisions in AES-128 theoretically possible when the plaintext is the same?

Is it theoretically possible to find $P$, $K$, and $K^\prime$ such that $E_K(P) = E_{K^\prime}(P)$ where $E$ is AES-128 and $K \ne K^\prime$? I'd imagine this would be infeasible, but is it actually impossible?


TikZ - Black Dot/Diamond in Center of All Diamond Shapes

I am making a flow chart and in the standalone TikZ file everything looks fine, but when I use \input into my thesis all of the diamonds have a small black diamond in the dead center of the shape. This happens with or without text in the node.  It's hard to include a working example due to the template of my thesis, but everything else looks the same.  Any idea what could be causing the small diamonds in the center?  \usetikzlibrary{shapes.misc,arrows, positioning}  \tikzstyle{startstop} = [draw, rectangle, rounded corners, top color=white, bottom color=red!30] \tikzstyle{process} = [draw, rectangle, align=center, top color=white, bottom color=blue!30] \tikzstyle{decision} = [draw, diamond, aspect=2, align=center, top color=white, bottom color=green!30] \tikzstyle{arrow} = [thick,->,>=stealth]  \begin{tikzpicture}  \node (start) [startstop] {start}; \node (plf) [below=of start, process] {text \\ text}; \node (3) [below=of plf, decision] {text \\ $||$ \\ text}; \node (4) [below=of 3, process] {text $\pm$ 1}; \node (5) [below=of 4, process] {text \\ text}; \node (6) [below=of 5, process] {text \\ text}; \node (7) [below=of 6, process] {text}; \node (empty1) [right=of 3] {}; \node (9) [right=of empty1, decision] {text \\ text}; \node (10) [below=of 9, process] {text \\ text}; \node (stop) [below=of 10, startstop] {stop};  \node[coordinate] (12) [left=of 3] {}; \node[coordinate] (13) [right=of 9] {};  \draw [arrow] (start) -- (plf); \draw [arrow] (plf) -- (3); \draw [arrow] (3) -- node[anchor=west] {no} (4); \draw [arrow] (4) -- (5); \draw [arrow] (5) -- (6); \draw [arrow] (6) -- (7); \draw [arrow] (7) -| (12) --  (3); \draw [arrow] (3) -- node[anchor=south] {yes} (9); \draw [arrow] (9) --  node[anchor=west] {no}(10); \draw [arrow] (9) -- node[anchor=south] {yes} (13) |- (stop); \draw [arrow] (10) -- (stop);  \end{tikzpicture}


If the method of FTL cannot be observed, does it still break causality

So, say we discover a method of FTL. However, anyone or anything that makes use of this FTL is unable to be observed by the outside world.   For example.  In the year 3000 a ship leaves Earth headed 6 light years away at twice the speed of light. A side effect of this FTL prevents outsiders from observing them. From the Earth's point of view the ship vanished into thin air. The ship arrives at it's destination, drops out of FTL, and can now be observed again. From the Earth's point of view, in the year 3009 their telescopes will see you suddenly appear at the destination 9 years after you left(3 to account for travel and 6 for the light to arrive back to Earth). However, after 1 year at the destination the ship decided to head home. They go into FTL and are once again un-observable. They arrive back at Earth in the year 3007, 2 years before their arrival at the destination is observable on Earth.  So, my question is does any of this in any way break the law of causality and effect, and if so how does it do so? As I understand it the fact that they can't be observed actually going faster than light that should allow them to get around causality.  And when I say they can't be observed during FTL to outsiders, I mean that completely. No heat escapes, no energy, no signals, no light, nothing at all.  Thank you very much


I have a problem : How to prove $$\dfrac{d}{dx}e^x=e^x\;?$$  My answer is \begin{eqnarray} \dfrac{d}{dx}e^x&=&\lim\limits_{h\to 0}\dfrac{e^{x+h}-e^x}{h}\\ &=&\lim\limits_{h\to 0}\dfrac{e^{x}e^h-e^x}{h}\\ &=&e^{x}\lim\limits_{h\to 0}\dfrac{e^h-1}{h}\\ \end{eqnarray} But I don't know to find $\lim\limits_{h\to 0}\dfrac{e^h-1}{h}$. So how to find it?  Note:  I cannot use L'Hospital rule.


I've got Windows 10 Pro and want to install Ubuntu on Oracle VirtualBox

Which Distro I should use if I've got Intel Core i5-4300U CPU x64?  Please, give certain variants, which you know will be installed for sure.


Variables are often adjusted (e.g. standardised) before making a model - when is this a good idea, and when is it a bad one?

In what circumstances would you want to, or not want to scale or standardize a variable prior to model fitting?  And what are the advantages / disadvantages of scaling a variable?


Photographs to Canvas Prints then Selling

Is it copyright infringement to take a photo of toys, collectibles and dioramas and have the image transferred to a print or canvas and then selling that item on Amazon or Etsy?


Who is this running kid wearing a shirt with Uchiha symbol?

There's a kid wearing a shirt with Uchiha symbol, but I have no idea who s/he is.    Who is this kid?


Say some electrons move through a wire in a circuit with just a battery and a resistor. We usually say that there is almost no voltage drop. If $\Delta V = 0$, then wouldn't that mean $\int E \, ds = 0$? Making $\Delta s$ smaller and smaller, we get that $E = 0$ everywhere. Some questions follow.  But don't the ends of a battery cause a non-zero electric field? Why is it that the field vanishes on the wire?  If we look at the voltage across the resistor, the drop in voltage is exactly the voltage of the battery. All of a sudden, that implies an electric field in the resistor.   Where did this field come from?  EDIT: Ok, I get that we want to mark it as a duplicate. At least link a question with an actual answer. I've looked at this question is, in fact, a duplicate. But here would be   To quote:      We are all indoctrinated to just assume that a battery creates an electric field in the wire. However, when someone asks "how does the field get into the wire and how does the field know which way to go?" they are rarely given a straight answer.   In general, how are the electric fields "structured" in a circuit?


How do you pick up money from traders in a settlement?

I have a traders stall in my settlement. Do I get the caps from him automatically or do I have to pick it up from somewhere? I can't seem to figure out if I've received any caps or not yet.


How to find invalid lightning code before it causes an error?

Why this is not a duplicate: This question is different than   My issue was caused by a missing attribute on a Lightning component. It would be nice to see some kind of error indicating a required attribute is missing instead of a generic error message.   Original question:  When I include my custom component (.cmp) inside of a standalone lightning app page (.app), I get a generic error:    This page has an error. You might just need to refresh it. Aura.loadComponent(): Failed to initialize application. An internal server error has occurred Error ID: 1165864723-88707 (1861465479)  To find out more details about what is causing the issue, I have:   Enabled debug mode so that I get un-minified js code.  Disabled caching  Installed Lightning Inspector for Chrome    When I load the page, I do not see errors in the Google Dev Tools console or Lightning console. I'm lost as far as how to find out details about the error...  Code  <aura:application extends="force:slds" > <!-- Header --> <lightning:layout class="slds-page-header" >     <lightning:layoutItem padding="horizontal-small">         <lightning:icon iconName="custom:custom54" />     </lightning:layoutItem>         <h1>          Friends with Boats     </h1> </lightning:layout> <lightning:layout>         <c:BoatSearchForm />  <!-- the error happens when I include this component--> </lightning:layout>  </aura:application>   How I debugged the issue   To find out the cause, I commented out the contents of the entire component and uncommented different sections until I ran into the problem. The error happened when I tried to add a  component to the page. The problem -  a missing required attribute 'label'.       <lightning:select>  <!-- missing attributes: 'name' and 'label' caused the error -->             <option value="">All types</option>     </lightning:select>   Takeaways:   If a lightning component requires certain attribute and it is missing, you will get a runtime error on a standalone .app page.  A lightning markup code can be saved even though it might be missing required attributes that cause runtime errors. Currently, Salesforce does not show a detailed error for invalid lightning markup. You only see a generic error. Adding a component to an App page through App Builder does not generate this error. Instead, when you open an app page in a tab, it generates a 'WARNING' in the Google Chrome Development Console. Is this a bug or by design?


Installing Ubuntu 17.04 to an external drive

I am pretty new to this and I am trying to boot Ubuntu from a 1Tb extra hard drive. I have the iso installed already but not sure where to go from there. I've read about burning it to the external drive, which isn't working out out for me. I've also seen some posts about partitioning but I'm not sure what that means.


states that the diagram of schemes    is "by general category theory" "a fibre product diagram". I tried to show this using the universal property, but didn't obtain anything useful. How do you prove $X\times_TY$ is a fiber product of $X\times_SY$ and $T$ with respect to $T\times_ST$?


How can alpha or beta emission maintain equal numbers of protons and electrons?

In radioactivity we know that a parent nucleus can disintegrate into daughter nuclei by emitting alpha or beta particles. If this is true then how can the daughter nucleus have as many electrons as protons?  For example, suppose a parent nucleus emits an alpha particle. Its mass number gets decreased by 4 and its atomic number gets decreased by 2 as it converts into a daughter nucleus. Now, how can the number of electrons and protons be the same?


I just bought a Google Chromebook HP 14 and I am very happy to be honest.  But I do miss my Ubuntu OS :), and the options available to use aren't a real native OS system but adaptations that sometimes do not work :(  Does anyone have an idea how to install with dual boot Ubuntu alongside Chrome OS?


I am building a little game and I've gotten to the point where I need to calculate data in the tips of abilities which is unique to each individual unit. So to do this I figured I'm gonna basically need a formula. I don't know if this is the way it's supposed to be done but here's what I've come up with  tip = 'Hurls a fire ball at your enemy, dealing [X] damage.'; formula = '5 * unit.magicPower * abilitylevel';   So  for each unit's tool tip I use  tip.replace('[X]', eval(formula))   Which appears to work fine, but what I'm concerned about is the safety of this code. It hasn't been once or twice that I've seen people discouraging the use of it. Are there any potential issues that may occur with the way I'm using eval()?


Should I buy a dslr kit or body with separate lens?

I came across 2 reputable sites here in our country selling DSLRs.  I wanted to buy a Nikon D90 kit with 18-55mm lens, cost 28,600.  The other store sells the 18-55mm lens for 3,308.   So it is cheaper to buy the body and lens separately from different merchants. I would save 1,692.  Is it okay to buy lens separately assuming it has the same specs with the kit?   Or is the lens from the kit better than the separate lens?


I am using SharePoint 2013.  There are four lists: List1 List2 List3 List4  With different users assigned to each List. Now, In the Home Page, I want to insert a Web Part named "Quick Links".  Whenever a user from List1 logs in, only List1 link should be displayed. All the other three links should be invisible for the List1 user.  Same applies to the other three List users too.  How can I achieve this?  Thanks


How can I find a closed form for the following sum? $$\sum_{n=1}^{\infty}\left(\frac{H_n}{n}\right)^2$$ ($H_n=\sum_{k=1}^n\frac{1}{k}$).


How to check which graphic card is used by the system?

I have laptop with two graphic cards one build in Intel and the other is nvidia GeForce. I've installed Xubuntu 16.04 and now I want to check which graphic card is used by the system. Probably build in because there are not drivers for Nvidia but I want to be sure.


How do I search for every file with executable permission (+x) in my system?

I need to find every single file that has executable permissions in my system, i think they end with x@.  I tried to ls every file and then grepping the output to match files with x@.  Like this:  ls -l | grep x@   But that just lists for the current directory and:  ls -ld | grep x@    Did not show all files. I need to search in all subdirectories. And I'm using FreeBSD tools (OS X).


Is it safe to fully cook a stuffed turkey the night before thanksgiving?

If I empty the cavity of stuffing after I cook it thoroughly, and reheat the turkey and stuffing separately the next day, will its consumption be hazardous?


How can a blender driver python script access scene properties like FPS?

I would like to be able to access properties of the current scene such as render.fps, frame_start, and frame_end from within a python driver script.  I have some data that is defined in terms of seconds, and I'd like the drivers consuming that data to work in two different scenes which have different frame rates.  edit: I tried using bpy.context.scene, but it turns out that is often wrong.  Let me be specific:  The driver is being evaluated to calculate the position of an object in scene "cave" and bpy.context.scene refers to scene "splash" .  In a 1-scene .blend bpy.context.scene works fine.  In a multi-scene .blend, bpy.context is not necessarily populated with what a reasonable person would consider 'the context of the driver'.


Required fields under Record Types and Subcategory type

I need to make those fields required under 2 conditions. Record type and Subcategory (picklist).   I stated doing Validation rules, for the first one: Record type: Passport Subcategory: Renewal and New Issue Field required: Request Received from Location  RecordType.Id = "012U0000000a3kVIAQ" && ( ISPICK ( Subcategory__c , "Renewal")  ||  ISPICK ( Subcategory__c , "New Issue") ) && ISBLANK ( Request_Received_from_Location__c)   I get a syntax error: Error: Field Subcategory__c is a picklist field. Picklist fields are only supported in certain functions.


I've got two villagers trapped in a one by one block, with another villager constantly farming potatoes to throw to one of the two villagers. For some reason though, whenever the villagers get thrown potatoes (They have been for over twenty-four hours of constant AFKING) I am in Minecraft Java edition, version 1.14.4. If anyone could help, thank you! Here are some screenshots showing my design.  One by one spot where Villagers stay   Spot where villager farms


Boot is 100% full and unable to solve it using 'apt-get -f install' command

Tried with apt autoremove, apt purge, apt-get -f install and few more. My present kernel version is 4.15.0-99 and old versions are {45,72,96}. As my terminal says I need little space on my boot for cleaning up and I have no space!


Physics models using (non-lorentzian) Indefinite metrics

I would like to understand better the role of indefinite metrics in physics. As far as I know, Lorentzian metric is the natural setting for Einstein's Relativity Theory. Somewhere I read something about theory modelling reality using more than one time directions, i.e. metric tensor of signature $(p,q)$ where $p,q\geq2$. The question is the following: which theories actually need indefinite metric of non-Lorentzian signature?


Run a NON-ELEVATED command from an already elevated batch file in Windows 10

I have a batch file that runs at startup with admin privileges (using Task Scheduler) and does some maintenance tasks. However, there is a problem. I have a certain maintenance task I need to do which must run as non-admin. If it runs as admin, it doesn't work. (It doesn't matter for our purposes what the task is or why it doesn't work as admin. I'd like to keep the question general so it can be useful for other people with a similar problem, regardless of the specific task.) Now, of course, I could just set up a separate task in the Task Scheduler that runs without admin privileges, which will do only that specific task. But I want to do several tasks in a specific order, some of them require admin privileges and some don't. So to summarize, the question is: can I execute a command without admin privileges from within a batch file that is already running with admin privileges?


Community Wiki checkbox missing in action

It looks like the Community Wiki checkbox is no longer appearing on the ask/edit question page, making it difficult to mark questions Community Wiki.  Where is it, and how is one supposed to mark a question as CW now?


i have custom alert dialog with two button inside. but each button have error null object reference, i want to make my relativelayout clickable and here is my java code :  RelativeLayout relaCamera; RelativeLayout relaGallery;  relaCamera = findViewById(R.id.relaCameraIntent); relaGallery = findViewById(R.id.relaGalleryIntent); ...... ...... private void pickFromGallery() {     LayoutInflater layoutInflater = LayoutInflater.from(this);     View view = layoutInflater.inflate(R.layout.upload_video_options, null);      final AlertDialog alertD = new AlertDialog.Builder(this).create();      relaCamera.setOnClickListener(new View.OnClickListener() { // error here         public void onClick(View v) {              Intent intent = new Intent();             intent.setTypeAndNormalize("video/*");             intent.setAction(Intent.ACTION_GET_CONTENT);             intent.addCategory(Intent.CATEGORY_OPENABLE);             startActivityForResult(Intent.createChooser(intent, "Select Video"), REQUEST_GET_VIDEO);          }     });      relaGallery.setOnClickListener(new View.OnClickListener() {// error here         public void onClick(View v) {              Intent takeVideoIntent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);             if (takeVideoIntent.resolveActivity(getPackageManager()) != null) {                 startActivityForResult(takeVideoIntent, REQUEST_VIDEO_CAPTURE);             }          }     });      alertD.setView(view);      alertD.show(); }   here is my upload_video_options.xml for customize the alert dialog:  <RelativeLayout         android:id="@+id/relaCameraIntent"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:layout_marginBottom="10dp"         android:layout_marginLeft="10dp"         android:layout_marginTop="20dp"         android:clickable="true"         android:gravity="center_horizontal"         android:orientation="horizontal"> <RelativeLayout         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:gravity="center_horizontal"         android:id="@+id/relaGalleryIntent"         android:clickable="true"         android:layout_marginBottom="10dp"         android:layout_marginTop="10dp"         android:orientation="horizontal">


Why am I getting a weird, blocky black background on my Windows desktop?

looks like this.  The icons show the desktop background behind them only after hovering over them. It doesn't happen all the time. The desktop became that way upon highlighting it, as you can see. I am currently using  as a stand in for my  while it is being repaired. I sent the Nvidia GPU in for repair because of this black background problem. Originally I had an Intel set up; I bought my Nvidia GPU just before building a new PC entirely. The parts I salvaged from my Intel system build were my PSU and the Nvidia GP I sent in. I never had this problem before I put the Nvidia GPU in my Intel build, but, now even in my AMD build and with an XFX card I still get this glitch/error. Note: I also salvaged my HDD and SSD from my old build. That could be the problem. All I have is Windows and it was a fresh install as of 2 or so months ago. This problem is (from what I can tell) cosmetic, I don't get any harmful system errors stops or glitches, but, I rather like my background so I’d like to have it fixed. As you can see in  I show the parts I salvaged from . Any part not shown in my Intel build was transferred from it to the AMD build. That’s all the information I have, though. Thanks to anyone taking the time to help.


If I have a projection $T$ on a finite dimensional vector space $V$, how do I show that $T$ is diagonalizable?


Turn image into geometric array of colours

Is there a tool like  available for Android or Windows systems? I'd like to  turn images into polygones/triangles like shown on the app site.


Cannot solve "Undefined reference to ..." Error

There is a problem with this code and I can't understand it. It seems the problem happens within the linking phase as I've googled, but in my case I think there is something wrong with my code, not in toolchains, but I just couldn't solve it after hours and hours of trying. I'd be happy if you help me correcting it. I'm using Code::Blocks, and the latest version of MinGW.  main.cpp  #include <iostream> #include <string> #include "threadsafequeue.hpp" using namespace std;  int main(){     threadsafe_queue<string> Q;     threadsafe_queue<string> X;     X.empty();     try{         string s;     }catch(empty_queue ex){         cout << ex.what() << endl;     }     return 0; }   threadsafe_queue.cpp  #include "threadsafe_queue.hpp"  template <typename T> threadsafe_queue<T>::threadsafe_queue(const threadsafe_queue& other){     std::lock_guard<std::mutex> lock(other.m);     threadsafe_queue<T>::data = other.data; }  template <typename T> void threadsafe_queue<T>::push(T new_value){     std::lock_guard<std::mutex> lock(threadsafe_queue<T>::m);     threadsafe_queue::data.push(new_value); }  template <typename T> std::shared_ptr<T> threadsafe_queue<T>::pop(){     std::lock_guard<std::mutex> lock(threadsafe_queue<T>::m);     if(data.empty()) throw empty_queue();     std::shared_ptr<T> const res(std::make_shared<T>(threadsafe_queue<T>::data.front()));     threadsafe_queue<T>::data.pop();     return res; }  template <typename T> void threadsafe_queue<T>::pop(T& value){     std::lock_guard<std::mutex> lock(threadsafe_queue::m);     if(data.empty()) throw empty_queue();     value = threadsafe_queue::data.front();     threadsafe_queue::data.pop(); }  template <typename T> bool threadsafe_queue<T>::empty(){     std::lock_guard<std::mutex> lock(threadsafe_queue<T>::m);     return threadsafe_queue<T>::data.empty(); }   threadsafe_queue.hpp  #include <exception> #include <memory> #include <mutex> #include <queue>  #ifndef THREADSAFE_QUEUE_HPP_INCLUDED #define THREADSAFE_QUEUE_HPP_INCLUDED  struct empty_queue : std::exception {     virtual const char * what() const throw()     {         return "The Queue is Empty.";     }; };  template <typename T> class threadsafe_queue { private:     std::queue<T> data;     mutable std::mutex m; public:     threadsafe_queue() {};     threadsafe_queue(const threadsafe_queue& other);      threadsafe_queue& operator= (const threadsafe_queue&) = delete;      void push(T new_value);      std::shared_ptr<T> pop();      void pop(T& value);      bool empty(); };  #endif // THREADSAFE_QUEUE_HPP_INCLUDED   And the error is :     ...\ThreadSafeQueue\main.cpp|9|undefined reference to   `threadsafe_queue::empty()'|


How do you usually backup/restore a fresh OS installation (instead of reformat)?

I usually reformat my home PCs regularly after sometime but since it's time consuming I thought I could just restore an entire OS from a backup.  How do you usually take a "snapshot" of a fresh OS installation, save it to a DVD, then restore it later as if you've just reformatted?


Is there any way to recover photos taken without a memory card?

I went out today and took over 75 photos with my Nikon Coolpix P100, but I didn't have a memory card in my camera. I'm now unable to retrieve any of the photos - is there any way to recover them?


In my SQL i have a table with a column id & Order.On website data is displayed according to id & Order.But we want to change the way data is displayed we want to randomize whole content..Can anyone please suggest SQL query for this.  rough database structure is below  city_id       city_name       city_order   1               xyz             1   2               geh             2   3               tre             3   Regards,


A word for a feeling of having forgotten something?

Is there any word or phrase to describe that nagging feeling you get when feels like you have forgotten something?  Edit : German words are welcome too!  Edie Edit : i see  i dont find any of  the answers satisfactory, i m moving this to German SE


How to make `apt-get upgrade` use less resources?

When I run sudo apt-get upgrade with a lot of packages on my low-end laptop, I get a perceptible system slowdown, sometimes with up to 3 second screen freezes.  Is there any way to mark this job as very low priority, i.e.  use very little CPU, MEM and HDD? I don't really care if it would make apt-get upgrade two hours longer to finish, I just want to keep working without the disruptions during the upgrade.


What is the relationship between Newton's gravitational constant and the Planck mass in $d$-dimensions?

Setting $h=c=1$ the familiar Wikipedia result is that the Gravitational constant, $G$ goes like $$ G = \frac{1}{m_{Planck}^2}$$ However, I suspect that this is only true in 4 or (3+1) dimensions? Or just 3 spatial dimensions. But how would this change if I work in d-dimensions? I guess I would have $$ G_d = \frac{1}{m_{Planck}^{f(d)}}$$ where $f(d)$ is a dimensional dependent number. But then what is $f(d)$?


I was wondering if it is necessary to use an Antivirus for Ubuntu 14.04 and which one should I use, I tried using the official documentation but the antivirus list there is for 10.04, I have no idea how to install ClamAV, I've tried what the ClamAV website says and what Ubuntu website says with no luck, I tried to find Avast for Linux but apparently it no longer exists D:


Is it legal to enter the US with a US visa while being a US citizen?

I'm a permanent United States citizen (by birth), but I don't have an SSN. I'm also a foreign citizen. My employer outside of the US wants to send me to work into the US for client on-site by asking for a work US visa that would be put into my foreign passport.  Is it legal to obtain and enter the US as a foreigner with such a visa, being at the same time a US resident? Can I enter the US as an American, but work as a foreigner?  I found :     A foreign national or alien entering the U.S. is generally required to   present a passport and valid visa issued by a U.S. Consular Official,   unless they are a citizen of a country eligible for the Visa Waiver   Program, or are a lawful permanent resident of the U.S. or a citizen   of Canada.


Code not wrapping in listings even though breaklines=true

I read that enabling breaklines in listings will make the included code wrap, but it does not in my case. Maybe something is interfering with this function?  Full code is shown below:  \ifdefined\docdefined \else     \documentclass[a4paper,twoside,12pt, openright]{report}     \input{include_start}     \begin{document} \fi  \definecolor{dkgreen}{rgb}{0,0.6,0} \definecolor{gray}{rgb}{0.5,0.5,0.5} \definecolor{mauve}{rgb}{0.58,0,0.82}  % START DOCUMENT  \begin{appendices} \makeatletter  \chapter{GUI Code} %%%%%%%%%%%%%%%%%    XML \section{Code XML}  \lstset{language=XML,  numbers=left,  frame=single,  commentstyle=\color{dkgreen},  basicstyle={\scriptsize\ttfamily},  keywordstyle=\color{blue},  %identifierstyle=\color{blue},  stringstyle=\color{mauve}, captionpos=t, showstringspaces=false, breaklines=true, breakatwhitespace=true, tabsize=3, caption={\protect\filename@parse{\lstname}\protect\filename@base\text{.}\protect\filename@ext}, }  \begin{frame}  \lstinputlisting{C:/Users/hab/SW/GUI/android/AndroidManifest.xml}      \end{frame}  \end{appendices}  % END DOCUMENT \ifdefined\docdefined \else     \input{include_end}     \end{document} \fi


I need to work in WGS 84 so I am trying to project my shapefile into WGS 84. Despite changing the default CRS to WGS 84, when I mouse over my shapefile I am still getting a different coordinate system (please see image). Now, if I right-click on my layer and go to properties, and choose WGS 84, the shapefile disappears from the map. So for whatever reason it doesn't seem to want to be this CRS. In ArcGIS you can use the toolbox to define a transformation - is there an equivalent in QGIS?   Changing the CRS makes my image disappear and that's the problem so ideally I need some suggestions beyond the usual steps () as to what might be happening.


Tell Wolfram Alpha that a variable is a natural number

How can I tell Wolfram Alpha that some variables are natural numbers, when I want to solve a equation?  An example of what I want to do:  $\binom{n}{k}\cdot p^k \cdot (1-p)^{n-k} = \frac{1}{\sqrt{n\cdot p \cdot (1-p)}}\cdot \frac{1}{\sqrt{2 \cdot \pi}} \cdot e^{-\frac{1}{2} \cdot \left(\frac{x-np}{\sqrt{n \cdot p \cdot (1-p)}}\right)^2}$ solve for $x$ with $n,k \in \mathbb{N}$, $0 \lt p \lt 1$.


What's the recommended way to move a VirtualBox VM to another computer?

I use VirtualBox 4.1.x on my Ubuntu machine and I’ve set up several virtual machines. Since there are several ways one can move a virtual machine in VirtualBox to another computer, I was wondering which one is the recommended way:   Use the “Import/Export utility.” Copy the entire virtual machine folder, containing the .vdi and .vbox files. Clone the VDI using “Virtual Media Manager” and then recreate a VM on the target machine but using the cloned VDI as the hard disk.   I have successfully used the 1st method several times and it has always worked. The problem is that after exporting and importing, the disk image is transformed into VMDK and not VDI anymore!  The 2nd method is probably the easiest but I’m not sure that simply copying the files will work or not on the target machine. When searching about this method, I found some people had problems in which they had to edit the VirtualBox.xml file to solve it!  At last, there’s the 3rd method, but it requires the extra work of creating a VM similar to the original VM configuration, which is not desirable.  It’s clear from the above explanation that my desired method is the 2nd one, but I need expert advice on this if it works or not. I don't want any XML editing getting in my way!  What’s the best method of safely transferring my VM’s to another computer with VirtualBox?


Will GNOME be updated to 3.30 in Ubuntu 18.04 by itself?

I know there are already reports on gnome-shell being a massive memory hog, but my question is this: Will gnome 3.30.1 ever hit Ubuntu 18.04, or am I stuck with this memory leakage forever until I upgrade Ubuntu?  Thanks  Edit: I'm asking about this particular instance. Will Ubuntu be updated to gnome 3.30.1 at some point in the future, or will I need to do it manually or upgrade Ubuntu?


Invalid string literal '^.*\s(\d+)\s.*$'. Illegal character sequence \s' in string literal

I want to use the below regex string:  private final String regex = '^.*\s(\d+)\s.*$';   In a Pattern:  private Pattern pattern = Pattern.compile(regex);   But I am getting this error:     Illegal string literal: Invalid string literal '^.\s(\d+)\s.$'. Illegal character sequence \s' in string literal.   What do I need to do to fix this?


query result took from wordpress database showing as question marks

I have saved Telugu language content in the database with utf8mb4_unicode_ci collation, and I am trying to extract that information from a different place (Not WordPress environment) everything ok but Telugu characters are showing as question marks.  this is the content stored in the database.     ఆ ఒక్క మాట తో కంపెనీ సర్వ నాశనం | #OURMINE | #VEVO This is the text i am getting.    ? ???? ??? ?? ?????? ???? ????? | #OurMine | #Vevo  Code i used to get the information.  <?php $con=mysqli_connect("localhost","db","pw","db");     mysqli_set_charset('utf8', $con);  // Check connection     if (mysqli_connect_errno())  { echo "Failed to connect to MySQL: " . mysqli_connect_error();  }  error_reporting(E_ALL ^ E_NOTICE);  $query = "SELECT * FROM TT_posts WHERE post_status='publish' AND ping_status='open'";  mysqli_set_charset('utf8', $query);  $result = $con->query($query); while ($row = $result->fetch_assoc())   {     ?> <?php     $image = "SELECT * FROM TT_posts WHERE post_parent='$row[ID]' AND  post_title='FEATURED' AND post_type='attachment'";   $result1 = $con->query($image);      while ($row1 = $result1->fetch_assoc())     $img = $row1[guid];   ?>
<?php echo '';?>

<?php echo $row[post_title];?>
  <?php } ?>   I don't know where i am wrong.


Difference between "in time" and "on time"

I have an appointment at 8 and I arrive there at 7:55, is it "on time" or "in time"? What about "the nick of time"?


How to prove $\lim_{n \rightarrow\infty} e^{-n}\sum_{k=0}^{n}\frac{n^k}{k!} = \frac{1}{2}$?

How to prove that: $\lim_{n \rightarrow\infty} e^{-n}\sum_{k=0}^{n}\frac{n^k}{k!} = \frac{1}{2}$  It's about the Normal Approximation to Poisson distribution. But it only calculates part of the Poisson distribution (only under expectation).  When we try to prove Normal distribution is an approximation of Poisson we use Characteristic Function. But I cannot use it here (because it's only part of a distribution).


Install brother dcp195c, receiving data but nothing happens, why?

Can someone please help me to install brother dcp195c drivers on Ubuntu v12?  Using the default driver, the printer says that it is receiving data but nothing happens.


I want to know how to select, copy the entire command from a command block (separately) and paste it into the chat or an another command block on Mac. I've already took a look to the other question similars, none of them responded at what I had in thought correctly. Thank you.


Is there an isomorphism between factor groups and subgroups of symmetric groups?

If H is a subgroup of G ( | G:H |=n, n > 1), then how can you show that G has a factor group G/N which is isomorphic to a subgroup D of the symmetric group Sn with |D| > 1.  I've been looking at Cayley's Theorem but it's not specific to the factor groups.


How to stop the 'Invalid name' error on Minecraft: Pocket Edition?

Every time I try and connect to my brother or cousins game it says Invalid Name. I have been playing Minecraft for a very long time and since this new update It loads for about one second then it says "Invalid Name!"


A natural morphism between $\operatorname{Proj}S$ and $\operatorname{Spec}A$

Suppose $S$ is a finitely generated $A$-algebra. I'd like to describe a natural morphism between $\operatorname{Proj}S$ and $\operatorname{Spec}A$. In exercise 6.3.F in Vakil's AG notes, we show that morphisms $X\rightarrow\operatorname{Spec}A$ are in natural bijections with ring morphisms $A\rightarrow\Gamma(\mathcal{O}_X,X)$. Why does this result gives us the desired natural morphism?


I just got a Lenovo ideapad 520, which includes a fingerprint scanner. It works fine for Windows, but when using Fingerprint GUI it simply doesn't detect the device. So I'm assuming I need a driver for this device, but I can't find any drivers online.  Does anyone know how to make this work in ubuntu 16.014?


How to replace "Open Powershell..." with "Open Command Prompt... context menu when clicking on empty space in folder?

When I click on an empty space in a folder view, I get this menu:    I'd like to replace Open PowerShell window with Open Command Prompt Here.  Note, that I am not right-clicking on a folder, but rather on an empty space within a folder.  P.S.  This question is about clicking on an empty space in Explorer, not clicking on a folder.


Is there any function in PHP that prints numerical 5 as five?

I want to show numerical 5 as "five". I couldn't explain more than this. Any help please.


Washington DC to London through Iceland - Do Indian passport holders need Transit visa?

I have an upcoming trip to London from Washington DC via Iceland. I hold an Indian passport, H1B visa in US, and visitor visa for UK. I have booked WOW air and it has a stop in KEF airport in Iceland. I have researched the immigration websites and saw that I may not need a transit visa. I did not get any information from the embassies through email and phone calls. Can anyone who has done this in the past, please advise on this?


Iphone stuck on 'Connect to iTunes" screen, I don't have a computer with iTunes available

I am stuck at work, and i tried to install ios 8.4 to my iPhone 5s, now it's stuck on the "Connect to iTunes" screen, well I don't have a computer with iTunes on it. My laptop is my work computer and it's and ASUS, and I can't install iTunes on any of the desktops here because it's not allowed. I desperately need my phone for work right now. I've tried resetting it, locking it, everything.


How is the minimum of a set of IID random variables distributed?

If $X_1, ..., X_n$ are independent identically-distributed random variables, what can be said about the distribution of $\min(X_1, ..., X_n)$ in general?


I have a HTML page. The problem is that I do not want to have the users to refresh the page each time I put on new content.  I have the following code in order to make sure that the page is not cached:       <meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate"/>      <meta http-equiv="Pragma" content="no-cache"/>      <meta http-equiv="Expires" content="0"/>   The problem is, I still need to do a refresh on the page in order to get the most current content to show up. Am I doing something wrong? Should I be using some other tags?


Why do electrons move towards anode in the Photoelectric effect experiment?

Consider a Photoelectric effect experiment apparatus as shown in Figure 11.1    The variation of photocurrent with the voltage applied across $\mathrm{A}$ and $\mathrm{C}$ is as shown in Figure 11.3.    My question –     Why is the current non-zero even if the voltage is zero?    Consider a situation in which the voltage across the plates is zero. Photons of sufficient frequency strike the outermost surface of the cathode, emitter plate $\mathrm{C}$. Electrons become free from the attraction of nucleus as their net energy becomes positive.  Why I think that there should be no net current?  As soon as photons strike the outermost surface of the cathode(assumed to be $1$ to $10$ atomic diameters thick), electrons become free. Now, as the electrons have kinetic energy, they'll come out of that outermost surface. Now, the electrons(with kinetic energy) should have an equal probability of going in every direction of the surface. So, around half of the electrons should go in the right direction towards the anode and strike it and half should go to the left, trying to penetrate the inner surfaces of the cathode plate.   Now, the electrons which will go to the right will face some field due to the space charge present in the tube but nevertheless, some electrons will definitely reach the anode plate. After they strike with the anode plate, they'll face some resistance but still, some electrons will reach the low resistance copper wires connected to the anode plate and milliammeter.  Now, consider the electrons which go towards left. They'll definitely face resistance from cathode plate but some will still reach the copper wire.  Now, as there is no potential difference applied between $\mathrm{A}$ and $\mathrm{C}$, there is no need of commutator and voltmeter. So, the ammeter is connected in series with the anode plates and cathode plates with copper wires.  Now, if there is steady state current in the circuit, electrons emitted to any one of the sides should dominate over the other. But the number of electrons emitted on both the sides is same, and all the electrons should face the same resistance as the current(electrons) should flow in a closed loop. But if the number and velocity of electrons coming from both the sides are same, there should be no net current. But there is. Why?  Edit –  From the answers of anna v and mmainville, it can be seen that the emission of electrons is dependent on the angle of emission of light.  But still, the question remains. If the electrons emitted towards anode have enough energy to complete the circuit and again reach the holes in cathode despite the resistance in between, the electrons emitted to the left should have enough energy to come to anode plate via copper wires and again get ejected through anode plate by the virtue of their kinetic energy and reach the cathode plate. In this case too, the current should be zero which is not true. Why?


Completely remove FlexNet Connect software

I installed software from Nuance recently, and they surreptitiously installed a program called FlexNet Connect (even with a custom install). FlexNet Connect does not provide useful information on its site, like architecture or security architecture documents.  shows its running as a service under NT AUTHORITY/SYSTEM and its image is hidden in C:\ProgramData. It also looks like its Adobe Air based, and Adobe is renowned for its insecure software. Finally, all it has done is served ads.  I think I would like to remove FlexNet Connect. There is no Uninstall option for the adware in Programs and Features | Uninstall. Additionally, it looks like its .  My question is, how do I completely remove FlexNet Connect software from this machine?    I still remember the days when Adobe used to distribute that Macrovision crap with its software. Macrovision would run as a driver, and it had a big security hole that went unpatched for years (as if Adboe needed help in making a machine insecure). As such, neither Adobe software nor Macrovision software are allowed on any machines under my control.


Reflection to Identify Extension Methods

In C# is there a technique using reflection to determine if a method has been added to a class as an extension method?  Given an extension method such as the one shown below is it possible to determine that Reverse() has been added to the string class?  public static class StringExtensions {     public static string Reverse(this string value)     {         char[] cArray = value.ToCharArray();         Array.Reverse(cArray);         return new string(cArray);     } }   We're looking for a mechanism to determine in unit testing that the extension method was appropriately added by the developer.  One reason to attempt this is that it is possible that a similar method would be added to the actual class by the developer and, if it was, the compiler will pick that method up.


Xmodmap syntax for rebinding Shift+Down to Up

I would like to rebind some keys on Linux via Xmodmap. Left and up cursor on my Acer (yes, I know) laptop have broke. I would like to map shift+down to up, and shift+right to left. Struggling to determine the syntax for this from man pages. This syntax is wrong, throws bad modifier, but captures the intent:  add Shift_L+Down = Up


How to disable release upgrade notification emails?

I have an Ubuntu 14.04 server installation that consistently sends a weekly email, from the root user, with the following content:  /etc/cron.weekly/update-notifier-common: New release '16.04.1 LTS' available. Run 'do-release-upgrade' to upgrade to it.   How do I stop these emails, without upgrading to 16.04? Is there a method that doesn't involve disabling the script mentioned in the first line of the email?  Ideally I'd like to allow /etc/cron.weekly/update-notifier-common to continue to run, calling the /usr/lib/ubuntu-release-upgrader/release-upgrade-motd and /usr/lib/ubuntu-release-upgrader/check-new-release scripts, but stop new release messages. It would be useful for these scripts to still warn if my current release becomes EOL.


Sources missing in /etc/apt/sources.list, how do I get them back?

Somehow my Ubuntu install can't find what I believe to be very common packages....  E: Unable to locate package php5-curl E: Unable to locate package php5-gd   I know this has something to do with my sources, however, I am not sure which source I need or which source these packages would be included in.  These are the commands I ran  sudo apt-get install php5-curl sudo apt-get install php5-gd   Here's the content of /etc/apt/sources.list:  # deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release amd64 (20111012)]/ dists/oneiric/main/binary-i386/  # deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release amd64 (20111012)]/ oneiric main restricted  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution.  ## Major bug fix updates produced after the final release of the ## distribution.  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team.  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team.  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team.   ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu oneiric partner # deb-src http://archive.canonical.com/ubuntu oneiric partner  ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software. # deb http://extras.ubuntu.com/ubuntu oneiric main # deb-src http://extras.ubuntu.com/ubuntu oneiric main  # deb http://repository.spotify.com stable non-free


Even though JRE 8 is installed on my MAC OS Yosemite, the error - " No Java Runtime present,requesting to install "

Even though JRE 8 is installed on my MAC OS Yosemite 10.10.3,while running the Android present in tools in sdk - the error - " No Java Runtime present,requesting to install " gets displayed in terminal- how do i solve this issue?  I wanted to install Xamarin test recorder - after installing they asked me to install Android sdk SDK is downloaded in Library/Developer/Xamarin/android-sdk Now when I run Android present in tools folder - I get the error - No Java run time I've installed JRE 8 with get the verified java version from their site Can someone please help!!


I am trying to use symbolic links with samba to link to a file outside the samba share directory. I've search around and have updated the config file with all the suggestions, but still no luck.   This is my smb.conf file:  [global] workgroup = WORKGROUP log file = /var/log/samba/log.%m max log size = 1000 panic action = /usr/share/samba/panic-action %d server role = standalone server obey pam restrictions = yes unix password sync = yes passwd program = /usr/bin/passwd %u passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* . pam password change = yes map to guest = bad user usershare allow guests = yes  allow insecure wide links = yes unix extensions = no  [Private] path = /media/hdd1/samba/private/ browseable = yes guest ok = no writable = yes valid users = @samba follow symlinks = yes wide links = yes   When I try testparm I get the following output  [global]     log file = /var/log/samba/log.%m     max log size = 1000     allow insecure wide links = Yes     panic action = /usr/share/samba/panic-action %d     usershare allow guests = Yes     unix extensions = No     map to guest = Bad User     obey pam restrictions = Yes     pam password change = Yes     passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* .     passwd program = /usr/bin/passwd %u     server role = standalone server     unix password sync = Yes     idmap config * : backend = tdb  [Private]     comment = House private samba share     path = /media/hdd1/samba/private/     wide links = Yes     read only = No     valid users = @samba   The follow symlinks is inclided in the config file, but not on the testparm output which I think is a bit odd.  The stripped down simple file structure is:  /media |- hdd1    |- datafolder    |  |-- file1    |    |- samba       |-- private           |-- Symbolic link to file1     Permissions are:  file1  root  plugdev link   samba sambashare


Show sent messages in native app (Android)

I'm developing an Android app that fetch client mobile and send an SMS in the background; I want the sent messages to appear in the native SMS app. This is my code and it works fine sending the message.  public class AlarmReceiver extends BroadcastReceiver {      @Override     public void onReceive(Context context, Intent intent) {          // For our recurring task, we'll just display a message         Toast.makeText(context, "I'm running from AlarmReceiver", Toast.LENGTH_SHORT).show();          //         String no = "70625783";         String msg = "message";          //Getting intent and PendingIntent instance         Intent i = new Intent(context, MainActivity.class);         PendingIntent pi = PendingIntent.getActivity(context, 0, i, 0);          //Get the SmsManager instance and call the sendTextMessage method to send message         SmsManager sms = SmsManager.getDefault();         sms.sendTextMessage(no, null, msg, pi, null);          Toast.makeText(context, "Message Sent successfully!",                 Toast.LENGTH_LONG).show();     } }   For simplicity I have hard-coded the mobile and the message content.


Is it possible to browse favorite questions by tag?

I am trying to figure out if it is possible to browse my favorite questions by tags (similar to how we browse normal questions), but I don't know exactly how I can do this.  Does anyone know how can I do that? Or is such functionality not currently available for favorite questions?


Getting the URL parameter into Lightning component using the "{! paramName}" expression

I am new to communities in lightning and I am trying to figure out a way to directly fetch the URL parameters into the lightning component attributes using the  {! urlParamName} expressions.  for example :   https://www.someurl.com/page?name=somename&surname=somesurname   My lightning component will be :   <aura:component>      <!-- Parameters Available in URL-->     <aura:attribute name="name" type="String">     <aura:attribute name="surname" type="String">      <!--It will get name parameter from URL directly-->     Name is : {!v.name}       <!--It will get surname parameter from URL directly-->     SurName is : {!v.surname}  </aura:component>   I am trying to figure out a way which cannot includes JS. Currently I am using Lightning JS to get these parameters.


How to get the Id of Inserted records from Database.Upsert?

I'm having this dilemma regarding the result for Database.Upsert(List, boolean).   Database.Upsert returns Database.UpsertResult and it provides as the Id of the record that was successfully inserted/updated.  However, if an ERROR happens during Insert, when you try to get the Id in UpsertResult via getId() function, you will see that the Id is NULL.  Now I understand this part because the record does not yet exist in DB but I need to return the UpsertResult to another method that needs to know which record failed.  Ex:  List<Asset> finalAssetList = new List<Asset>();     //Loop exists here that fills up finalAssetList      List<Database.UpsertResult> upsertAssetResult = Database.upsert(finalAssetList, false);     List<ResultMessage> rmList = new List<ResultMessage>();     for(Database.UpsertResult ur : upsertAssetResult) {         ResultMessage rm = new ResultMessage();         rm.error_message = ur.getErrors();         rm.recordId = ur.getId();         rmList.add(rm);     }      return rmList;   Please take note that ResultMessage is an inner class whose variables are recordId and error_message.  If an Error happens during Insert, my rmList will contain a record with NULL in its recordId.   Is there any way that I can circumvent this?  Thanks.


What is the best method in jQuery to add an additional row to a table as the last row?  Is this acceptable?  $('#myTable').append('
my data	more data
');   Are there limitations to what you can add to a table like this (such as inputs, selects, number of rows)?


Science Fiction Book: two alien factions fighting, eventually humans get involved

So my dad and I were talking about books last night, and he mentioned a science fiction book series that he read when he was younger than me. I'm currently a young adult, not even 20. It had to have been published before the 2000s then. He talked about how much he really liked it and how he wished he could find them again. I want to do some hunting on the internet to see if I can find them and surprise him. Okay, this is all the info I know and it's unfortunately not very much. He doesn't remember any of the character's names, the author, or cover art.   It was a series, not a stand alone novel The plot involves two alien factions fighting against each other "Kind of like the Federation and Dominion," my dad said. Humans aren't initially in the story, but they come in later when one of the factions employs the human's help in fighting At least one of the factions doesn't like fighting, but they do it cause they have to (like the Federation from Star Trek). Because of this, when the faction finds Earth, they are surprised to find a myriad of governments and the humans seem to like fighting. The humans fight on one side, they kick all kinds of butt, but after the war the aliens are mystified. "Well, what do we do with them now?" Sort of a thing. Earth at the time of this novel was probably in the 80s or 90s, I'm wagering.    Any help or guesses would be appreciated. It would be great if I could surprise my dad with a copy of the first book in the series.  EDIT: It is indeed The Damned Trilogy by Alan Dean Foster my dad was looking for. I was hoping it would be in my local library system, but I did not see it. So I showed him the cover art and he instantly recognized it. I'll probably buy it for him for his birthday. Thank you to everyone that helped


Using something like scp but when I've logged in already

I want to copy a file via ssh when I've logged in. What scp does is that it copies the files by login, password, path. What I want is to be able to do the same thing when I'm "inside", ideally without providing the login and password:  $ ssh root@123.123.243.63 root's password:  Welcome to ..... Last login: .... root@folder1:~# // How do I download (or upload) the files when I'm here?


How can I create an infinite login loop for a specific user?

Well I know the question is weird, but i have a user "Bob" and I want only bob's account to be stuck in infinite login loop. Please note I don't want to get out of a login loop..I want this particular user to be stuck in infinite login loop.   How do I do this?


Privilege progress indicator interferes with (old) Stack Exchange dropdown

I know I'm late with this; this could be the last bug report about the old topbar. But the text on the privilege progress indicator (on your profile page) appears above the dropdown menu coming from the Stack Exchange button, as can be seen in the picture below.     Changing the z-index property of .s-progress-bar._badge .-info, .s-progress-bar._privilege .-info from 2 to 1 solves the problem.    The new menu seems to have a high enough z-index so that this is no longer a problem anymore:


I want to change the PASS_MIN_DAYS = (whatever value is set) to PASS_MIN_DAYS = 15 using a script.The file it's in is /etc/login.defs.


Why can positive rationals be not well ordered?  If we define the relation to be greater than(>), then every subset will have a least element.  Or why are positive or even integers not well ordered?  By the same logic we can always find a least element in any subset.  I know I am wrong at some very fundamental point, but please explain it to me.


Find multiplicative inverses for elements in U(20)

I am self-learning abstract algebra using Abstract Algebra: An Introductory Course by Gregory Lee. I come across this group: $$U(20)=\{1,3,7,9,11,13,17,19\}$$ I have managed to find two pairs of multiplicative inverses, namely: $$3\cdot 7=1$$ $$13\cdot 17=1$$ I am wondering how to find the multiplicative inverses for $9$, $11$, and $19$. For example, for $19$, the closest I can get is: $$9\cdot 19=11$$ Also, must inverse be unique in a group? In the other words, can two elements have the same inverse? Thank you.


From de Broglie's equation, we know that there is a relation between wavelength, the Planck's constant and the momentum of light. $λ= h/mv$ We know that the velocity of light is a constant...... so cant we find the mass of a photon (I am sure you cant but what is preventing us from thinking this way?)


Compact set plus a closed set is a closed set

Let $(X,\|\;\|)$ be a normed vector space over $K$ and let $A,B\subseteq X$ be s.t. $A$ is compact and $B$ is closed. I want to prove that:  $$(\alpha A+\beta B)\;\text{ is closed }\;\forall \alpha,\beta\in K$$ So, given our function $\odot$ as in , my attempt goes like this: Let $\alpha,\beta\in K$. If $\alpha=\beta=0$, clearly $$\alpha A+\beta B=\{0\}\text{ is closed}$$ Now, since $\odot$ is continuous and $A$ is compact, we have that $\;\forall \alpha\neq0,\;\alpha A=\odot(\alpha,A)\;$ is compact and thus closed.  Then, let $\;y\in \beta B$ so,  $$ y=\beta b_y $$ for some $b_y\in B$. But, since $B$ is closed, there exists $\{b_n\}_{n\in\Bbb N}\subset B$ s.t. $b_n\xrightarrow[n\to\infty]{}b_y$ So let $y_n=\beta b_n\;\;\forall n\in\Bbb N$. Thus, $\{y_n\}_{n\in\Bbb N}\subset \beta B$ and $\|y_n-y\|=\|\beta b_n-\beta b_y\|=|\beta|\|b_n-b_y\|\xrightarrow[n\to\infty]{}0$ Thus, we get that  $$\forall y\in\beta B\;\exists\;\{y_n\}_{n\in\Bbb N}\subset \beta B \text{  s.t.  } y_n\xrightarrow[n\to\infty]{}y$$ so $\beta B$ is closed $\;\forall \beta\in K$. Now, $$ \text{Let }x\in (\alpha A+\beta B)\Rightarrow\;\exists\;a^*\in\alpha A\;\land\;b^*\in\beta B\text{  s.t.  } x=a^*+b^* $$ so, since $\alpha A$ and $\beta B$ are closed, $$ \exists\;\{a_n^*\}_{n\in\Bbb N}\subset\alpha A\text{  s.t.  }a_n^*\xrightarrow[n\to\infty]{}a^*\\ \exists\;\{b_n^*\}_{n\in\Bbb N}\subset\beta B\text{  s.t.  }b_n^*\xrightarrow[n\to\infty]{}b^* $$ so, taking $x_n=a_n^*+b_n^*\;\forall n\in\Bbb N$ is clear that $x_n\in (\alpha A+\beta B)\;\forall n\in\Bbb N$ and $$ \|x_n-x\|=\|a_n^*+b_n^*-a^*-b^*\|\le\|a_n^*-a^*\|+\|b_n^*-b^*\|\xrightarrow[n\to\infty]{}0 $$ so $x_n\xrightarrow[n\to\infty]{}x$ and, since this happens $\;\forall x\in (\alpha A+\beta B)$, thereby $(\alpha A+\beta B)$ is closed $\;\forall \alpha ,\beta\in K$  What do you think? Did I miss something?


If we have that $\tau \leq \nu$ are stopping times and that $X_n$ is a submartingale, how to show $E(X_{\tau \wedge n}) \leq E(X_{\nu \wedge n})$

If we have that $\tau, \nu$ are stopping times and that $\tau \leq \nu$, if $X_n$ is a submartingale, how can I show that $E(X_{\tau \wedge n}) \leq E(X_{\nu \wedge n})$? Is there a way to characterize it by a Martingale transform or is there a simpler idea? thanks


Appending item to list makes it unselectable

I'm trying to create a sort of html select dropdown using the bootstrap dropdown. In the list I'm hiding the default selected value but on change I delete the chosen option from the list and add the default value to make it selectable again etc. like this:  Selected: Cool  Option: Code  Option: Bro   When selecting Code it becomes:  Selected: Code Option: Bro Option: Cool  Now this works well when an option has not been selected before but when an option already has been selected you cant select it again.. Anyone who knows what I'm doing wrong here?    var from = $('#selected_from').data("curfromcoin"); var to = $('#selected_to').data("curtocoin");  $('#from_coin a').on("click", function() {   $('#selected_from').html($(this).data('fromcoin'));   $('#selected_from').data('curfromcoin', $(this).data('fromcoin'));   $("#from_drop").append($("
" + from + "
"));   $("#from_drop li").remove(":contains('" + $(this).data('fromcoin') + "')");   from = $('#selected_from').data("curfromcoin"); });
   <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">    Cool   </button>

Code

Bro


Ubuntu 20.04 Chromium Snap: cannot pin Webapp shortcuts to dock

If you're on Ubuntu 20.04 and create a webapp through Chromium Snap (via menu, 'More tools', 'Create shortcut...', tag 'Open as window', right-click the .desktop file on your desktop and choose 'Allow Launching') you will notice the app cannot be pinned to the dock (since there's no option 'Add to Favorites'). Also, the webapp will not be found when you search for it.


convexity proof of a function including ln and sums

$$f(x_1,\dots,x_n)=\sum\limits_{i=1}^nx_i\ln x_i-\left(\sum\limits_{i=1}^nx_i\right)\ln\left(\sum\limits_{i=1}^nx_i\right)\rightarrow R_{++}^n$$  How can I prove this is convex on $R_{++}^n$? I tried using the Hessian and couldn't prove it. There is a solution using the gradient and Jensen but very long and complicated.


Can't update to Java SE 8u181 from 8u171 on El Capitan

as part of my update routine, I wanted to upgrade from the installed Java SE 8u171 to Java SE 8u181. Before anyone asks, yes, one software DOES need Java (LibreOffice).   Problem is, the install window abruptly closes, and the installed version stays at 8u171, according to the Java preference pane.  In a terminal windows, I found things even more confusing:     $ java -version java version "1.8.0_161" Java(TM) SE Runtime   Environment (build 1.8.0_161-b12) Java HotSpot(TM) 64-Bit Server VM   (build 25.161-b12, mixed mode)   I don't know exactly what is happening. Console doesn't say why it's failing. I already tried to manually install 8u181 from the .dmg found on Oracle's website, but the result is the same. Same goes when I try to install the update in Safe Mode.  Any clues?


Best way to do multi-row insert in Oracle?


avoid spaces and apostrophes problems with ls in a awk script

I have many identical files in two (local) devices, and it happens that I have renamed some, only in one device (A). I found the following way to rename the identical files in the other device (B), according to the new names in device A, so that at the end I have identical both files and namefiles, without deleting or copying anything, but only renaming. Indeed I found an interesting answer is  from Hai Vu (the second answer). The script works, but there are two problems:  with spaces in filenames: the names are truncated by spaces. and with apos (') in filenames  The script (rename-identical-files.awk) is /^total/ {next} # Skip the first line (which contains the total, of ls -l)  {     if (name[$5] == "") {     name[$5] = $NF     print "# File of size", $5, "should be named", $NF  } else {     printf "mv '%s' '%s'\n", $NF, name[$5]  } }  and it is called from command line (in the destination folder): awk -f ~/rename-identical-files.awk <(ls -l /model-folder-path) <(ls -l) | sh   The problem seems ls command, that has limits (at least) with spaces and other characters in filenames. What code should I write, to avoid space (and apostrophes) problems?


Referencing, when you can assume that readers and you know "what you talk about"? Is it unnecessary? I.e. if I can be sure that any reader of my paper that's of a sufficient professional level, should agree on what I'm saying, then is it necessary to reference in order to "prove a view"? This applies to e.g. definitions or methodologies or such. For example, if I write a paper on image segmentation that's read by people who also study image segmentation or are experienced in it, then would it be unnecessary to cite "elementary texts" on something that may be considered "basic knowledge in image segmentation".


Copy paste of const and non-const methods

Consider the following code:   IStorage has const and non-const get methods. The concrete implementation defines them, but the definition is just copy-paste.  I could not call one get method from another because of the const mechanics of C++.  Is there any way to avoid this copy-paste?


When you search for a village to attack, how does Clash of Clans choose an enemy village? Does it only choose villages by people with a similar amount of trophies, who are in the same league, does the town hall level also matter or is there anything else that influences the matchmaking?


Resetting Windows 10 after system compromise by "Google"

My Grandad was having trouble logging into his Gmail account yesterday. He managed to find and call the "Google tech support helpline", who claimed to be from Google and claimed that his account has been hacked several times and they needed to remote access into his computer to "clean out the viruses". They also told him to leave his machine on for the rest of the day while they were connected through remote access so they could continue their work.  They said they would call again today to continue the "work" and sort out his issues with logging in to his account and provide him with a bill for their services. I'm surprised they didn't try and bill him yesterday, which makes me think they won't call today and their aim was simply to infect his machine.  Luckily, he contacted me about this and I've told him to leave his computer off for now and not to get in touch with them again.  The question is, what would be the best way to secure his computer now? I expect a simple "Reset Windows" from within his computer won't be enough to ensure that there is nothing malicious remaining on his machine - considering the attackers had remote access.  I believe he upgraded to Windows 10 from a previous version so he doesn't have a licence key - if I reinstall from a clean Windows 10 installer made from another machine, will it recognise his hardware and automatically activate Windows?  There's also the files - he has a large amount of music and photos which would need to be recovered (no backups available). Would an antivirus scan from a Linux machine suffice?


Why doesn't my general SE logged in status carry over to Super User?

I'll describe this like a bug report because it seems like a bug.  I was logged into SE and able to move freely from site to site (among the sites I have already joined) -- EXCEPT Super User.  To get to Super User, I had to log in again (same email address, same userid, same password).  I do not remember ever having had this problem previously.  Another anomaly: Super User was then automatically added to my list of communities.  Is it supposed to work this way?


I would like to know if I would need a 1.5m x 2m Backdrop, what's the size of canvas I've to create on photoshop?Thanks!


How to write text that takes up no space?

How does one write text such that whatever comes next is placed as if the text had not been written?  Edit: More specifically, I would like to place text in the top-left corner of a tikzpicture by writing the text right before the figure and anchoring the figure as if the text had not been written. Here is an attempt I made that does not work:  \documentclass{article} \usepackage{tikz} \begin{document}  \newcommand{\imagetop}[1]{\vtop{\null\hbox{#1}}}  \makebox(0,0){a} \imagetop{%     \begin{tikzpicture}         \draw (0, 0) rectangle (1, 1);      \end{tikzpicture} } \makebox(0,0){b} \imagetop{%     \begin{tikzpicture}         \draw (0, 0) rectangle (1, 1);      \end{tikzpicture} }  \end{document}


Killing a specific item without scoreboard in minecraft

I am trying to kill for example a dragon head (as a "dropped item") only not all items with /kill so I want to know how to specify what type of item I want to kill without using /scoreboard


Deriving Euler-Lagrange for Electrodynamics Lagrangian

For $\mathcal L = -\frac14 F_{\mu\nu}F^{\mu\nu}$ I would appreciate some help evaluating  $$\frac{\partial \mathcal L}{\partial(\partial_{\mu}A_{\nu})}.$$  I've found  $$\frac{\partial \mathcal L}{\partial(\partial_{\mu}A_{\nu})} = -\frac14\frac{\partial}{\partial(\partial_{\mu}A_{\nu})}(\partial_{\lambda}A_{\sigma} - \partial_{\sigma} A_{\lambda})(\partial_{\lambda} A_{\sigma} - \partial_{\sigma} A_{\lambda}) $$  $$ = -\frac14 \frac{\partial}{\partial(\partial_{\mu}A_{\nu})} \left( 2\partial_{\lambda}A_{\sigma}-2\partial_{\lambda}A_{\sigma}\partial_{\sigma}A_{\lambda}\right)$$ $$ = -\frac14 4\left(\partial_{\nu} A_{\mu} - \partial_{\mu} A_{\nu}\right) \qquad(*)   $$ $$ = F_{\mu\nu}$$  but I cannot understand the step taken to get to $(*)$. In my attempt, I take the chain rule to obtain   $$\frac{\partial \mathcal L}{\partial(\partial_{\mu}A_{\nu})} = -\frac12 F_{\mu\nu} \frac{\partial(\partial_{\alpha}A_{\beta} - \partial_{\beta} A_{\lambda})}{\partial(\partial_{\mu} A_{\nu})}$$  $$= -\frac12 F_{\mu\nu}(1) - \frac12 F_{\mu\nu} \frac{\partial(\partial_{\beta}A_{\lambda})}{\partial(\partial_{\mu}A_{\nu})}$$ $$ = -\frac12 F_{\mu\nu} - \frac12F_{\mu\nu}\delta_{\beta\mu} \delta_{\lambda\nu} = -\frac12 F_{\mu\nu} - \frac12 F_{\beta\lambda}$$  which seems to give me almost what I want, but I must have run into an error because this expression no longer makes sense, as each term should be indexed by $\mu,\nu$.   So my 2 questions are: how do we get to $(*)$ and where did my attempt go wrong?


Python transpose function printing out unexpected values

I have the following python function attempting to transpose an 8x8 matrix, A, store its values in the zero 8x8 matrix, B, and return B. I realize that the most readable and/or algorithmically efficient implementation would involve only two for loops, but for the sake of the larger program I'm trying to build the transpose function needs to be in a similar format to the following:  def transpose(A, B, n):     tmp = [[0, 0, 0, 0, ]]     for m in range(4):         j_start = m*2         j_finish = j_start + 2         for k in range(4):             i_start = k*2             i_finish = i_start + 2             for i in range(i_start, i_finish):                 for j in range(j_start, j_finish):                     tmp = A[j][i]                     B[i][j] = tmp                     print "At B[" + str(i) + "][" + str(j) + "] = " + str(A[j][i])     print B     return B   When I print the value at each iteration of the innermost for loop, it prints out the correct value (which you can verify at home):  At B[0][0] = 1 At B[0][1] = 9 At B[1][0] = 2 At B[1][1] = 10 At B[2][0] = 3 At B[2][1] = 11 .... At B[6][7] = 63 At B[7][6] = 56 At B[7][7] = 64   but the ensuing print and return statements yield  [[8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64], [8, 16, 24, 32, 40, 48, 56, 64]]   What's the reason for the disparity between printed values from within the loop and those that are returned?


I recently bought a Transformer so that I can make an ionic lifter but it has a max 30 amp output and I’m sure that is way too much for what I need plus Since I have this plugged straight into the wall I’ll definitely need an ac to dc rectifier which at most goes to about 5 amps So my question is how can I reduce the output amps so that I don’t mess up this rectifier as soon as I get it.   Btw the transformer is a 3000W YaeCCC Auto Transformer


Is it possible to add something like shebang to make jar file executable on Windows?

In Linux world one can just add shebang to the jar file and create an executable, it's widely  though whether this is a good practice or not. My question would be - is there something similar I can add to make the jar executable both on Windows and *nix platforms?


difference between these two way of writing function in javascript

I would like to know what is difference in writing in below 2 ways :  Approach 1:  var onCallback = function(result) {      alert('way1'); };  function1(onCallback);   Approach 2:  function2(function(result) {     alert('way2'); });


Chromatic polynomial of non-tree graphs?

If x ≥ 3 and G is not a tree, show that $χ(G, x) < x(x−1)^{n−1}$  I think if G is connected, the result is trivial.  How can I deal with the case that G is not connected?


Slashes in single route parameter or other ways to handle a menu tail with dynamic number of params

According to the , a route defined as below should trigger the specified controller for both /hello/bob and /hello/bob/bobby:  _hello:   path:     /hello/{names}   defaults: { _controller: \Drupal\mymodule\Controller\Main::Controller }   requirements:     _access: 'TRUE'     names: .+   In the case of a request to /hello/bob/bobby the {names} param would be "bob/bobby" (slash intact) and it would be up to the controller to break that down into multiple variables or to leave it as a single string. The trick to that is the altered regex (".+") used to filter that {names} param.  This  also implies that custom regex can be used to allow slashes in a route param (at least in Symfony 2).  If I try this against Drupal 8.0.0-beta15 it does not work and the specified controller is only triggered for a request to /hello/bob. However, I can confirm that this used to work in previous betas (I think up until ~beta13).  Has something changed in the way Drupal integrates with the Symfony routing component that would explain this? Perhaps there is an alternate way to accomplish the passing of slashes in routing params? I know there is a  in core, but I'm not sure if that could explain things.  I also know that route subscribers are available to manage dynamic route structures. However the case I am working on requires an almost infinite combination/number of dynamic parameters at the end of a base path (but which are trivial to parse in my controller). I'm also trying to avoid query strings (e.g. /hello?names[]=bob&names[]=bobby) for this case.  Mainly I'm just confused as to the disconnect with the Symfony documentation, which seems to state that this should be possible.    Additional Notes  After posting this question I discovered this discussion in the D8 core queues: . It seems to conclude that "menu tail" support (which is essentially what I am after) will officially be dropped in D8. That discussion ended 3 years ago and so I can only guess that some of the more generalized implementation specifics were not fully realized until recently (~beta13). This may explain why I've only now noticed this change.  I'm guessing that Drupal (not Symfony) is now generating a 404 response based on the raw slash-delimited request before any of the Symfony-specific routing logic further dissects the route (and it's param-specific regex, etc.). If this is the case it could explain why technique above stopped working. I am still wondering however if there are alternative ways to deal with this need that avoid using query params and custom route subscribers.


What should be the minimum observation size per group in a random effect

I searched on SO and CV for a minimum sample size per group for a random effect in a mixed-effects model but failed to find relevant answers. Some say there should be the minimum of 6 groups to be included as a random effect variable, but what should be the minimum number of observations per group? I have 22 groups in total, but half of the groups (11) has only one observation. In my personal thought (without any reasoning..), too many groups with single observations is likely to reduce the reliability of a statistical result. For your reference, below shows the result of my model. If the variance between groups is not reliable, I would like to use a glm with gamma family (log-link) instead of a glmm. Can somebody help a noob, please? Generalized linear mixed model fit by maximum likelihood (Laplace   Approximation) [glmerMod]  Family: Gamma  ( log ) Formula:  FD ~ DRS + Fine * CloudX + TempX + WindX + HumX + (1 | ID)    Data: data       AIC      BIC   logLik deviance df.resid    1300.7   1330.0   -640.3   1280.7      129   Scaled residuals:      Min      1Q  Median      3Q     Max  -1.4398 -0.6472 -0.1104  0.3297  4.7963   Random effects:  Groups   Name        Variance Std.Dev.  ID    (Intercept) 0.09426  0.3070    Residual             0.41693  0.6457   Number of obs: 139, groups:  ID, 22  Fixed effects:                        Estimate Std. Error t value Pr(>|z|)     (Intercept)           3.0099171  0.7855672   3.832 0.000127 *** DRS                  -2.5087985  1.9044682  -1.317 0.187731     Fine                  0.0027865  0.0008587   3.245 0.001174 **  CloudXScattered       0.6813028  0.3419755   1.992 0.046343 *   TempX                 0.0366588  0.0219830   1.668 0.095396 .   WindX                -0.0120540  0.0309304  -0.390 0.696748     HumX                 -0.0010427  0.0086787  -0.120 0.904371     Fine:CloudXScattered -0.0283622  0.0113815  -2.492 0.012704 *   --- Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1  Correlation of Fixed Effects:             (Intr) DRS    Fine   CldXSc TempX  WindX  HumX   DRS         -0.544                                           Fine         0.062 -0.759                                    ClodXScttrd -0.529  0.231  0.150                             TempX       -0.846  0.178  0.256  0.582                      WindX        0.168 -0.030 -0.204 -0.541 -0.483               HumX        -0.801  0.565 -0.205  0.396  0.511 -0.005        Fn:CldXSctt  0.188  0.112 -0.282 -0.770 -0.386  0.411 -0.036 fit warnings: Some predictor variables are on very different scales: consider rescaling convergence code: 0 Model failed to converge with max|grad| = 0.00749811 (tol = 0.002, component 1) Model is nearly unidentifiable: very large eigenvalue  - Rescale variables? Model is nearly unidentifiable: large eigenvalue ratio  - Rescale variables?


I am newbie, is learning to make the program connect to the mysql database, but there is an error. i want to know how to look for url jdbc: mysql:  public class KoneksiDatabase { private static Connection koneksi; public static Connection getKoneksi(){     if (koneksi == null) {         try {             String url = "jdbc:mysql://localhost/universitas";             String user = "root";             String pasword = "kendo";              DriverManager.registerDriver (new com.mysql.jdbc.Driver());             koneksi = DriverManager.getConnection (url, user, pasword);         } catch (SQLException t) {             System.out.println ("Eror Java Database Connection");         }      }     return koneksi; }


This is a very naive question. Every manifold (assumed to be paracompact) is a CW-complex?  Thanks.


Showing that $f = 0 $ a.e. if for any measurable set $E$, $\int_E f = 0$

Let $(X, \mathcal{B}, \mu)$ be a measure space and $f$ a measurable function on $X$ and suppose that $\forall E \in \mathcal{B}$ we have that $\int_E f = 0$.  Then I want to show that $f = 0$ almost everywhere (a.e.).   Suppose for sake of contradiction that $f \ne 0$ a.e. Then $\not\exists E \in \mathcal{B}$ s.t. $\mu(E) = 0$ and $f(x) = 0$, $\forall x \in X - E$  Then $\{x : f(x) \ne 0\} = A$ is not measure zero so that either $\mu(A) > 0$ or $A \notin \mathcal{B}$. Now if $\mu(A) > 0$ then it is easy to see that $\int_A f \ne 0$ so that we have a contradiction of our original hypothesis that $\forall E \in \mathcal{B}, \int_E f = 0$. But if on the other hand $A \notin \mathcal{B}$, I cannot no longer appeal to $\int_A f \ne 0$ since $\int_A f$ is non-sense.  So I'm having trouble with this part of the argument.


if $f(x) = \int_{t=1}^{t=x^2} t\sin^2(t)\operatorname d\!t$ then $\frac{\operatorname d\!f(x)}{\operatorname d\!x}=?$

$$f(x) = \int \limits_{t=1}^{t=x^2} t\sin^2(t)\operatorname d\!t$$  Do I use U-substitution and have the answer as $$f'(x) = 2x*x^2\sin^2(x^2)$$  Or does this question require integration by parts?   Thanks.


Any good ORM tools for Android development?

Anyone working on the Android ('gPhone') have or know of a place where I can find a good ORM tool for it? The code is written in Java, and the database is SQLite. What I would like to find is a tool that given the object definition, can auto-generate the tables and the CRUD functions (that would be awesome), or, barring that, a tool that can take the table definition, the object definition, and auto-generate the CRUD functionality. The rub is that all of this must happen within the Android framework, which has its own conventions as to how database access works.


Are for in loops guaranteed to run in a specific order?

I'm trying to come up with a js object minification function, one that would take an object and turn it into something like "VS4g3as" or whatever. The unminification would require the object prototype since I'm only storing the values.   Anyways, question is that if I run a for-in loop on an object like "for (var key in object)...", are the keys returned guaranteed to always be in the same order regardless of browser, platform, weather or whatever?   I'm trying to decide whether or not I need to enforce some kind of ordering like alphabetical.


I'm using ubuntu 13.10 but i want to install windows so, i downloaded a windows iso  but how to Make bootable disk/usb in ubuntu 13.10 of windows iso


Why should the interface for a Java class be preferred?

would report a violation for:  ArrayList<Object> list = new ArrayList<Object>();   The violation was "Avoid using implementation types like 'ArrayList'; use the interface instead".  The following line would correct the violation:  List<Object> list = new ArrayList<Object>();   Why should the latter with List be used instead of ArrayList?


Why is movement the consequence of a force and not the other way around?

I know this question might seem a bit ambiguous, but hear me out.  Suppose we have a table on which we exert a certain force $\vec{F}$. If $\vec{F}$ has a big enough magnitude, and is set in the right direction, the table will start to move. Let's suppose that the table is moving at constant velocity.   Conversely, if we consider that we are imposing a constant velocity $\vec{v}$ on one end of the table, a reactive force will be created.   It always seems to me, in textbooks and in lectures, that force is the cause of movement and not the other way around. Is this completely true? Or have I just stumbled upon some linguistic quirk that lead to a fallacy?  My knowledge of certain (fundamental) abstractions in pure physics is a bit limited, so I'd like to know the answer, in as much detail as possible. Keep in mind that I'm not asking for equations like Newton's second law, or for some mathematical derivation per se. I would like to understand both formally and intuitively why one phenomena causes the other.


Is there a shortcut to change tabs on safari?

Is there a keyboard shortcut to switch tabs on Safari?