Requirejs ignore loading error for optional dependency
requireJS optional dependency
What is the name of the depiction of concentration with raised eyebrow called? I have a question about inheritance in Java.  I have two classes A and B , and class B, inherits from A:  public class A {      public A() {          System.out.println("Hi!");      } }   public class B extends A {      public B() {          System.out.println("Bye!");      }       public static void main(String[] args) {          B b = new B();      } }   When I run program B, the output is:  Hi! Bye!      Question : why the constructor of class A is invoked, when I create and object of class B ?    I know that B inherits everything from A - all instance or class variables, and all methods, and in this sense an object of B has all characteristics of A plus some other characteristics defined in B. However, I didn't know and didn't imagine that when I create an object of type B, the constructor of A is also invoked. So, writing this:  B b = new B();   creates Two objects - one of type B, and one of type A.  This is getting interesting,   can somebody explain why exactly this happens? Why isn't it possible to combine vendor-specific pseudo-elements/classes into one rule set? Uniform distribution on the surface of unit sphere With the new permission model for Marketing Cloud Installed Packages, there is a problem with the "Read"-Scope for Data Extensions.  If an installed package is granted the permission/scope "Data Extensions - Read" the API-Call fails with HTTP 403 "Forbidden".  How to provide read access to Data Extensions?  Related documentation: What is the difference between the words which and that?  For example I have the following sentences:   “I have a car which is blue.” “I have a car that is blue.”   Are there any rules specifying usage of which and that? Largest Mass Diffraction How to show $ \sin x \geq \frac{2x}{\pi}, x \in [0, \frac{\pi}{2}]$? I have tried the following: $$ f(x) = \sin x-\frac{2x}{\pi} \\ f'(x)= \cos x-\frac{2}{\pi} \\ f''(x) = -\sin x \leq 0 $$ But this doesn't seem to be heading in the right direction as it would appear $f'(x)$ is decreasing and has a zero within the domain, so I'm not sure how this might be used to prove the inequality. Is it possible to change the color of a single bar when the bar plot is based on symbolic values? I am beginner in LaTeX, trying to use it for industrial documents. I wonder if there is a way to change the color of only one bar of the plot below, ie "TestDetails", to illustrate it is a local macro and not a LaTeX keyword. I have been trying to experiment with point meta, but could not find a way.  \documentclass{article} \usepackage{filecontents}  \usepackage{pgfplots}  \usepackage{pgfplotstable} \pgfplotsset{width=.95\textwidth, compat=newest}   \begin{document}  \begin{filecontents}{data.csv} {Occurences}, {keyword} 215, item 159, SI 134, subsubsection 106, TestDetails 58, caption \end{filecontents}  \pgfplotstableread[col sep=comma]{data.csv}{\datatable}  \begin{tikzpicture} \begin{axis}[ /pgf/number format/.cd,1000 sep={}, width=0.8\linewidth,height=6cm, xbar, xmin=30, xmax=250, xtick=\empty, enlarge x limits={value=0.1, upper}, enlarge y limits=0.1, ytick=data,  y dir=reverse, xlabel= {}, y tick label style={major tick length=0pt}, yticklabels from table={\datatable}{[index]1}, nodes near coords, nodes near coords align=horizontal, ] \addplot [draw,fill=blue!50]table[ y expr=\coordindex, x index=0]{\datatable}; \end{axis} \end{tikzpicture}  \end{document} I am looking for a textbook that treats the subject of Special Relativity from a geometric point of view, i.e. a textbook that introduces the theory right from the start in terms of 4-vectors and Minkowski tensors, instead of the more traditional "beginners" approach. Would anyone have a recommendation for such a textbook ?  I already have decent knowledge of the physics and maths of both SR and GR ( including vector and tensor calculus ), but would like to take a step back and expand and broaden my intuition of the geometry underlying SR, as described by 4-vectors and tensors. What I do not need is another "and here is the formula for time dilation..." type of text, of which there are thousands out there, but something much more geometric and in-depth.  Thanks in advance. Do the -ing and to-infinitive "verbs" that follow catenative verbs always take the grammatical function of "noun"? I'm wondering whether or not the verb form that follows a catenative verb has the grammatical function of a noun or of a verb, and whether or not it depends on the first catenative verb.  "I like to run" "I like running"  the -ing and the to infinitive can easily be switched in this sentence, and it seems to be implying "I like [the act of[running]]", so both the infinitive and the gerund are nouns.  "I like to run marathons"/"I like running marathons"   These seem like they might still be nouns but need "verb powers" to take the object, and then these sentences really turn into "I like [the act of [running marathons]]"/ "I like [to be in the state of [running marathons]]".  Is this true for both the -ing (and so it would be a gerund) and the to-infinitive? Are they, sort of, initially verbs so that they can take the object, and then the verb + object becomes a noun phrase?  If this is true, I'm also wondering if the same rules apply for a catenative verb such as "start".  "I started to run in the mornings" "I started running marathons in 2008"  "start" is a catenative verb that isn't a cognitive/emotion verb, and specifically suggests action. So what is the grammatical function of the to-infinitive and -ing verb forms? are they verbs? are they nouns? It just seems incorrect to say that their grammatical function is a noun, but everything I've seen on the internet is pretty vague. I've also seen that to-infinitives are never verbs, but only from one source and it just doesn't seem right to me.  So any ideas on the true grammatical function of the -ing and the to-infinitive after a catenative verb? And is it universal across catenative verbs, or does it depend on the verb category? What's your preferred way of getting current system status (current CPU, RAM, free disk space, etc.) in Python? Bonus points for *nix and Windows platforms.  There seems to be a few possible ways of extracting that from my search:   Using a library such as  (that currently seems not actively developed and not supported on multiple platform) or something like  (again no activity since 2007 it seems and no support for Windows). Using platform specific code such as using a os.popen("ps") or similar for the *nix systems and MEMORYSTATUS in ctypes.windll.kernel32 (see ) for the Windows platform. One could put a Python class together with all those code snippets.   It's not that those methods are bad but is there already a well-supported, multi-platform way of doing the same thing? If $\mathrm{Tr}(A)=0$ then $T=R^{-1}AR$ has all entries on its main diagonal equal to $0$ Align  elements side by side My machine was updated today to Ubuntu 16.04.2. However, the kernel is still "4.4.0-62-generic". What happened (it seemed that the principal advantage of the 16.04.2 version was the update of the kernel to 4.8) ? Do I have to make a fresh install ? Preventing reverse search engines from finding the origin of your image? I am planning to make a game, where I give the user an anime related image and they have to guess where its from.  However, most of the images, specially from popular anime are easy to use on Google reverse search to find and pin point the anime.  I've tried to see if I could make so it would not recognize the image but unhappily my tricks were not good enough.  Original image:    Grey-scale with horizontal flip:    Watermarking:    Puzzling the image with grey-scale:    Grey-scale with horizontal and vertical flip worked for this image but doesn't always work:    Also the above mentioned methods are rather easy for people to guess the anime.  I would like to know if there any good trick, that I could use on my images to make so it would not work on reverse search engines and yet not be so overcomplicated that I can implement on my program.  For example grey-scale, cropping, flipping are rather easy things to achieve in C#. Syncing folders outside Dropbox using Symbolic Links and Junctions I've been reading a lot of information on this and yet I'm still unsure if its possible.  What I want to achieve is: sync a folder that is outside Dropbox and any changed to that folder or the files within get mirrored to the Dropbox folder and the Dropbox server.  This is what I've tried: I've install Link Shell Extension. Picked a folder with 10 pictures inside and created a junction for it inside the Dropbox folder. When I delete a pictures from inside the original folder (outside Dropbox) the change is reflected in the Junction folder inside Dropbox Folder, not on the server.  The exact same behaviour with the Symbolic Link option.  If I manually select Pause Syncing from Dropbox system tray icon and then Resume syncing = it uploads the changes to the server.  I know I can move all my files inside Dropbox folder and create the junctions/symlinks at their original locations but I want to do it the other way around.  Also what is the difference between choosing the Junction and Symbolic Link Option in regards to a folder?  Thank you. For which $x$ exists sum $1 + 2 + 3 + \ldots + n$, where $n &gt; 3$, which has notation $xxx\ldots x$?   In other words, I am looking for a sum of natural numbers which gives a result which has all same digits, e.g. $5555555$ or $22222222222222222$, or whatever else.  How to find this series and how to proof it for all possible series?  I have found the following examples:   $1 + 2 + 3 + \ldots + 10 = 55$ $1 + 2 + 3 + \ldots + 11 = 66$ $1 + 2 + 3 + \ldots + 36 = 666$     And what about next series which ends with (different) repeating $x$? Hot to find and proof it? What pins on a nRF51822 do I connect to a STM32 programmer? I want to be able to program a  with  but I'm not sure what pins on the actual chip I should use, and all the guides seemed to be using a different chip ssh to private-ip I have a computer with CentOS (computer A) that configured as has an private ip 10.150.5.141 (with restricted firewall), can access internet and my ArchLinux VPS (computer B) with real ip w.x.y.z  How can I make another pc (computer C) that could access computer B to connect to computer A, but computer C cannot connect to computer A directly (because it's on A's own private network)?  I know that a tunnel can open local ports to another computer:port, but how to do the opposite?  I want to access computer A using ssh through computer B but computer B cannot access computer A, because the network on computer A is restrictive (can go out, but can't go in, because I have no access to their router)  I want something like this:  ssh -connect-to w.x.y.z:22 -open-port vvv -forward-to 10.150.5.141 -port 22   so that when I ssh w.x.y.z:vvv from computer C it will forwarded to private network 10.150.5.141:22.