Unexpected behavior with python list of dictionary when setting values for dictionaries with same key
List of lists changes reflected across sublists unexpectedly
Run true multiple process instances of gnome-terminal Assume I wield a Whip in one hand and a dagger in the other.  If a creature moves from 5ft to 10ft it has technically moved out of my reach (dagger), but at the same time it is still inside my reach (whip). When does it provoke opportunity attacks from me?  I am fully aware that this would not enable me to make off-hand attacks since the whip is not a light weapon, just to cut that issue out of the question. Calculate the sum of inverse values of ${n\choose 0}, {n\choose 1}, ... {n\choose n}$ Calculate $$A={1\over {n\choose 0}}+ {1\over {n\choose 1}}+ ...+{1\over  {n\choose n}}$$  and  $$B={1\over {n\choose 0}}- {1\over {n\choose 1}}+ ...+{(-1)^n\over  {n\choose n}}$$     My idea for $A$ is some probabilistic reasoning. Color the sets $$\{\}, \{1\}, \{1,2\}, \{1,2,3\},...\{1,2,...,n\}$$ and ask our self what is the probability that I choose colored set among all sets. Clearly this is exactly ${n+1\over 2^n}$ and on the other side it is $A$:  probability that I take empty set is ${1\over {n\choose 0}}$,   probability that I take colored set with 1 element is ${1\over {n\choose 1}}$  probability that I take colored set with 2 elements is ${1\over {n\choose 2}}$  and so on ...   So $A ={n+1\over 2^n}$. But I have no idea how to attack $B$. 3D graphics render as though no illumination How can Star Trek: Countdown ever be considered canon? Install Biber in MiKTeX on a 64-bit version of Windows Update: As of summer 2015 Biber is also included in the 64-bit repositories for MikTeX. There is no need to install Biber manually any more, it can simply be installed via the Package Manager just like other packages.   The question  describes how to use Biber with MiKTeX. But on the 64-bit version of MiKTeX Biber isn't installed.  How it is possible to install Biber on a 64-bit version of Windows?  Can I use this ? Better HTTPS support for Stack Exchange sites Is there a easy way to test ubuntu on new notebooks before buying it? Is there an easy way to check a notebook's hardware compatibility with ubuntu before you buy it?  I really don't want to buy a notebook home and find several bugs caused by the hardware.  I know that DELL has some notebooks which are pre-installed ubuntu12.04LTS, i.e. the new xps. But what about other notebooks? isn't there a way to quickly check a notebook's compatibility with ubuntu?  A way I can see is using a LiveCD/ubuntu stick and boot in ubuntu first, then run some tests. But the problem is: how to make these tests in a short time automatically??? and how can I check the hardware compatibility? I know that I can use lshw or hardinfo to get informations, but only having the information is not enough, there are still some possibilities that your hardware has a bug. For instance, Lenovo T410i's wireless driver has a bug which causes extremely low speed internet connection, I googled a lot and recompiled the driver to fix that bug. So this is the kind of situation I'm trying to avoid.  Any help is appreciated. Proof of $(a+b)^{n+1}$ I have to do proof of $(a+b)^n$ and $(a+b)^{n+1}$ with mathematical induction.  I finished the first one $(a+b)^n = a^n + na^{n-1}b+\dots+b^n$.  I however have trouble with the second one, I don't know what to start exactly. Any help/hints? Video showing up as white space On  question, there is a YouTube video in , on the Android app the video shows up as a white space. There is no indication that it is a video.  Would it be possible to show the video in the app or link to the video on YouTube instead? What is the default password of the sudo? I visit some forums, it tells that the default password is password, but it doesn't work, how can I determine the password? Full Wi-fi/ethernet signal but no internet Strange math notation, vertical bar with parentheses. So I was reading "Resistance Distance" (D. J. Klein, M. Randić) (Journal of Mathematical Chemistry 12(1993)81-95) when I came up with strange notation.  From the paper:  The graph adjacency matrix is defined as: $$A_{xy} = (x|A|y) =  \begin{cases} 1/r_{xy} &amp; x \sim y \\ 0 &amp; \text{otherwise}  \end{cases}$$  The graph degree matrix of a graph is defined as:  $$\Delta_{xy} = (x|\Delta|y) = \delta(x,y) \sum_{z}^{\sim x} 1/r_{xy}$$  $$ |\phi) \equiv \sum_x |x)  $$  My main question is what does the combination of the vertical bar parentheses mean. Thanks in advance. Trigger to use HTTP callout and update record with the results I have been trying to integrate Google Shortener API into my salesforce org. I wrote a class to make the call out, but am having difficulty bringing the value back into the record. I have a custom object called "referral_advocate__c" with a field called "Short_URL__c". Anytime the field "unique_ID__c" has a value, I am wanting to send this value with a static URL to google shortener and then save the response value to "referral_advocate__c.short_URL__c" on the record. This is the class to make the call out:  public class URLshort {  final string urls = 'https://www.myurl.com'; referral_advocate__c adv = new referral_advocate__c();  @future(callout = true) public static void URLshortner() {      HttpRequest req = new HttpRequest();     HttpResponse res = new HttpResponse();     Http http = new Http();      req.setEndpoint('https://www.googleapis.com/urlshortener/v1/url?key=myapikey');     req.setMethod('POST');     req.setHeader('Content-Type','application/json');            req.setBody('{"longUrl":+urls + adv.unique_reference_number_c}');       try {         res = http.send(req);         System.debug(res.getBody());     } catch(System.CalloutException e) {         System.debug('Callout error: '+ e);         System.debug(res.toString());     }   }  }   The after insert trigger on "referral_advocate__c" I wrote is not firing correctly. How do I return the results from this class and update the field "short_URL__C" with the returned value from a trigger? Why could the dwarves only enter Erebor with the secret passage? Please bear with me as I've never read any of the LOTR books or the Hobbit, only seen the movies so far...  But when the sunlight fades and the dwarves think they've lost their only chance to enter Erebor using the secret passage and the key, they turn around to head home. Why is it that the dwarves would be unable to enter Erebor the way they did years ago, using regular doors to get inside? I'm assuming that's how they entered Erebor years ago? Adding the consensus to review's history Quantum entanglement faster than speed of light? recently i was watching a  on quantum computing where the narrators describes that quantum entanglement information travels faster than light!  Is it really possible for anything to move faster than light? Or are the narrators just wrong?  Regards, Proving $f(x,y,z)=\big(\frac{x}{a+x+y+z}, \frac{y}{a+x+y+z}, \frac{z}{a+x+y+z} \big)$ is injective Let $a\in \mathbb{R}$, $a\neq 0$, and $E=\{(x,y,z)\in \mathbb{R}^3:a+x+y+z\neq 0\}$ and $f:E\rightarrow \mathbb{R}^3$ defined by $$ f(x,y,z)=\big(\frac{x}{a+x+y+z}, \frac{y}{a+x+y+z}, \frac{z}{a+x+y+z} \big) $$ Show that $f$ is injective.    I've been trying to prove it directly by showing that if $f(x_1,y_1,z_1)=f(x_2,y_2,z_2)\Rightarrow$ $x_1=x_2, y_1=y_2,z_1=z_2$. But I get a system of equations which I'm find difficult to deal with. Any help would be greatly appreciated. I use babelbib and I have a source with two authors. Contrarily to when using the plain bib style, as soon as I switch to babplain, the author names are formatted like this:  [1] Müller, Jan und Eva Schulze: Name of the book, 2015.   While I would like both author names to be formatted the same way, that is one of these:  [1] Müller, Jan und Schulze, Eva: Name of the book, 2015. [1] Jan Müller und Eva Schulze: Name of the book, 2015.   sources:  % test.tex \usepackage[ngerman]{babel} \usepackage[fixlanguage]{babelbib} \selectbiblanguage{ngerman} \bibliographystyle{babplain} \bibliography{test}  % test.bib @manual{foo,     author = "Müller, Jan and Schulze, Eva",     title = "Name of the book",     year = "2015", }   I can fix it by specifying and {Schulze, Eva}, but that way all is treated as the last name, that cannot be the solution, can it? What's the frequency of filesystem check on boot? What is the maximum number of times the root filesystem on this computer can be mounted before it is automatically checked?