I have an org.bson.Document that I can convert into a JSON:  for (Document dc : list) {         String doc = dc.toJson();     }   And the String looks like:  { "_id": "C:\\Users\\santi\\Desktop\\2010-documents.biased\\99\\2010-99-086.html",   "data": {         "german": 1,          "metadata": 1,          "inform": 20,          "almanac": 1,          etc etc         }  }   I'm stucked at figuring how to access to the "data" field and get all the key-value values and store them into a HashMap or Map. I thought about spliting the array and getting some substrings etc but doesn't seem like a good way.
What is the best way to convert a JSON code as this:  {      "data" :      {          "field1" : "value1",          "field2" : "value2"     } }   in a Java Map in which one the keys are (field1, field2) and the values for those fields are (value1, value2).  Any ideas? Should I use Json-lib for that? Or better if I write my own parser?
Can anyone can suggest where I can freely download ArcObjects SDKs for ArcGIS?  I am using version 10.2. Is there any way to specify a suggested filename when using data: URI? fitch style proof problem regarding rule of inferences Okay I have the following fitch proof almost figured out, from here I know I have to move forth in conlcuding but I don't know what I am missing  (2 premises)  S → (R ∨ P)  P → (¬R → Q)   my work below  new scope assume S   Rule: > elim  R ∨ P  New scope assume R  Q∨R     Rule: V intro  End scope – (new scope assume P)  ¬R → Q         Rule: > Elim  my confusion comes where I go from here  Q∨R            rule Taut Con ??  Goal:├ S → (Q ∨ R) Accessing laptop's hard drive when OS won't boot How to use Alt+Shift to switch keyboard layouts? I recently upgraded to Ubuntu 13.10, with the new keyboard handling system. The little "switch keyboard" option does not let me set it to Alt+Shift. How can I get this keyboard binding, as I have absolutely no interest in using the Mac-esque Super+Space combo? What torque for caliper brakes onto carbon-alloy forks? I've recently got a new bike with a . This comes with deep-drop calliper brakes (Shimano R451 Dual Pivot). The first time out I bumped one of the brakes and it twisted around the single attachment bolt and rubbed on the rim.  I managed to easily twist it back by hand and carry on, however I thought the bolt probably needs tightening. The question is: How tight can it be?  As the fork is part carbon I've so far only dared to take it up to 4Nm, but it still seems possible to twist the whole calliper around with a bump of the hand. Maybe that's normal? Perhaps it's easier to bump around because of the longer deep-drop lever. Should I be aiming to get it really secure?    I'm not sure whether the brake mount in the fork is all carbon, or some of it is alloy underneath, but either way I'd like to know what a sensible torque is. As far as I can see from the  there is no such specification. How can I find this out? Uniqueness in existence of a bilinear form Let $E$ be a finite dimensional vector space over field $\mathbb R$ with $E^*$ as the dual space of $E$.($\dim E=n$)   $\Omega^P(E):=\{ \alpha\colon \overbrace{E\times\cdots\times E}^{p- times}\rightarrow \mathbb R\  \ , \alpha \text{ is alternating multilinear map}\}$ $\Omega^P(E^*):=\{ u\colon \overbrace{E^*\times\cdots\times E^*}^{p- times}\rightarrow \mathbb R\  \ , u \text{ is alternating multilinear map}\}$  I wish to prove that there exist an $\textbf{unique}$ bilinear form $B\colon \Omega^p(E^*)\times\Omega^p(E)\rightarrow\mathbb R$   such that for all $ f_i\in E^* \ , u_j\in E^{**}\simeq E \qquad  i,j=1,\cdots,p$, it has the following rule:  $B(u_1\wedge\cdots\wedge u_p,f_1\wedge\cdots\wedge f_p)=\det[f_i(u_j)]$.  $\wedge$ is wedge product between alternating maps i.e. $\alpha\wedge\beta(v_1,\cdots,v_{p+p})=\dfrac{1}{p! p!}\displaystyle\sum_{\sigma\in S_{p+p}}sign(\sigma)\alpha(v_{\sigma(1)},\cdots,v_{\sigma(p)})\beta(v_{\sigma(p+1)},\cdots,v_{\sigma(p+p)})$  How can I do this? How can I reduce the file size of a scanned PDF file? I have a 72.9MB PDF file that I need to shrink into under 500KB.  The file was a JPEG image that I had scanned, and then converted to pdf. Discrete Probability: Four dice are thrown, what's the probability that... Four dice are thrown, what's the probability that:  a) None of them fall higher than three?  b) None of them fall higher than four?  c) That four is the highest number thrown?  So for a, I wanna think about the denominator first. There are 6 possible outcomes for each dice, and we have four dice. So we're technically picking r out of n objects, aka picking 4 possible values out of 6. So the denominator/sample space should be $6^4$ right?  Now this is where I'm getting tripped up. Order technically shouldn't count, because we only care about the quadruplets that don't have a value higher than 3. I might be wrong, maybe I am, but could someone explain a bit more? My professor stated that typically in the sample space/denominator, we want order to count.   So I'm trying to think of the numerator now, so we want to find the probability that no values appear higher than 3, so some events that can occur are: $(1, 1, 2, 3), (1, 2, 2, 3), (1, 1, 1, 1)$ etc. Again, I can't see why order should count here, because if we only are concerned about what appears rather than how they appear, then we can say $(1, 1, 2, 3)$ is equal to $(1, 2, 1, 3)$? So if order does not count, and we have replacement, then does this lead the case where we use $$\binom{n-1+r}{r}$$to find out the probability?   I'm pretty sure if I can do a), I could prob do b), but if someone could maybe lead me in the right direction for c) I would appreciate that too! These days, the standard way to present differential calculus is by introducing the Cauchy-Weierstrass definition of the limit. One then defines the derivative as a limit, proves results like the Leibniz and chain rules, and uses this machinery to differentiate some simple functions such as polynomials. The purpose of my question is to see what creative alternatives people can describe to this approach. The nature of the question is that there is not going to be a single best answer. I have several methods that I've collected which I'll put in as answers to my own question.  It's not reasonable to expect answers to include an entire introductory textbook treatment of differentiation, nor would anyone want to read answers that were that lengthy. A sketch is fine. Lack of rigor is fine. Well known notation and terminology can be assumed. It would be nice to develop things to the point where one can differentiate a polynomial, since that would help to illustrate how your method works and demonstrate that it's usable. For this purpose, it suffices to prove that if $n&gt;0$ is an integer, the derivative of $x^n$ equals $0$ at $0$ and equals $n$ at $1$; the result at other nonzero values of $x$ follows by scaling. Doing this for $n=2$ is fine if the generalization to $n&gt;2$ is obvious. All odd primes except $5$ divide a number made up of all $1$s Okay, so I have worked on this problem and even though I can see it is true I just don't know how to show it.  Here it goes.  Question:  Show that every odd prime except $5$ divides some number of the form $111 \ldots 11$ ($k$ digits, all ones).  Thank you my friends! TV documentaries invariably show the Big Bang as an exploding ball of fire expanding outwards. Did the Big Bang really explode outwards from a point like this? If not, what did happen? I've recently run into a proof that claims that $1 - 1 + 1 - 1 + 1 - 1 ... = \frac{1}{2}$ that proceeds as follows:     Let $S = 1 - 1 + 1 - 1 + 1 - 1 + ...$. Then $$S = 1 - (1 - 1 + 1 - 1 + 1 - 1 ...) = 1 - S$$ Therefore, $2S = 1$, so $S = \frac{1}{2}$. QED   I was under the impression that this sum doesn't converge, and therefore this step of the proof is invalid:     Let $S = 1 - 1 + 1 - 1 + 1 - 1 + ...$   That is, it's not even valid to suppose that the sum is equal to some (implicitly real or complex) number $S$, and therefore the reasoning that follows is meaningless because $S$ doesn't exist and therefore has any properties we want it to have.  Is the reasoning I've given above correct? That is, is it correct for me to claim that the proof fails because $S$ doesn't exist?  (I've heard that there are techniques for evaluating divergent integrals by using complex analysis and Taylor series, so perhaps there's another way to prove that the summation is $\frac{1}{2}$; I just wanted to see whether my reasoning is sufficient to explain why this particular proof is incorrect. If the proof actually is correct, then I stand corrected!)  Thanks! How to select html nodes by ID with jquery when the id contains a dot? If my html looked like this:  &lt;td class="controlCell"&gt;     &lt;input class="inputText" id="SearchBag.CompanyName" name="SearchBag.CompanyName" type="text" value="" /&gt; &lt;/td&gt;   How could I select #SearchBag.CompanyName with JQuery? I can't get it to work and I fear it's the dot that's breaking it all. The annoying thing is that renaming all my id's would be a lot of work, not to mention the loss in readability.  Note: Please let's not start talking about how tables are not made for lay-outing. I'm very aware of the  and try hard to use it as much as possible. How do I move Ubuntu dock to bottom on Ubuntu 17.10 and later? Just upgraded from Ubuntu 17.04 to Ubuntu 17.10.  Please help me to shift the side bar (aka Ubuntu Dock) to bottom.   I tried running the following command which used to work with older Ubuntu releases   gsettings set com.canonical.Unity.Launcher launcher-position Bottom   but it's not working. eGPU Vega 56 (Blackmagic) Mac + cycles problem Hello I just got the AMD Radeon RX Vega 56 (blackmagic eGPU Pro) yesterday  plugged it in to my brand new Mac mini (Mojave), it shows up in the menubar and as an alternative as a render engine,. My question is, can I use this eGPU for cycles renders? (Blender 2.80)  Very grateful for your responses. Nginx rewite rules 403 error I am having trouble with converting .htaccess files to nginx. I have 3 .htaccess files. The first .htaccess file is located in the document root and is as follows:  Options +FollowSymLinks RewriteEngine On RewriteRule ^img-(.*)\.html img.php?id=$1 [L] RewriteRule ^slide-(.*)\.html slider.php?id=$1 [L] RewriteRule ^page-(.*)\.html page.php?name=$1 [L] RewriteRule ^contact\.html$ contact.php [QSA,L,NC]   The second .htaccess file is located in a folder called upload:  RewriteEngine On RewriteCond %{HTTP_REFERER} !^http://(.+\.)?foo\.com/ [NC] RewriteCond %{HTTP_REFERER} !^$ RewriteRule .*\.(jpe?g|gif|bmp|png)$ nohotlink.gif [L] &lt;Files ~ "\.(php|sql|php3|php4|phtml|pl|py|jsp|asp|htm|shtml|sh|cgi)$"&gt;   order allow,deny   deny from all &lt;/Files&gt;   And the third and final .htaccess file is found in a subdirectory of the upload folder named "small":  RewriteEngine Off   Now I have created a folder in /etc/nginx called includes and made 3 seperate .access files with these rewrite rules:  For the first .htaccess file located in the document root directory I have created an file in /etc/nginx/includes called root.access. In this file I have:  # nginx configuration   location /img {  rewrite ^/img-(.*)\.html /img.php?id=$1 break;  }  location /slide {      rewrite ^/slide-(.*)\.html /slider.php?id=$1 break;  }  location /page {      rewrite ^/page-(.*)\.html /page.php?name=$1 break;  }  location /contact {      rewrite ^/contact\.html$ /contact.php break;  }   For the second file located in the "upload" folder I have crated a file in /etc/nginx/includes called upload.access. This file contains the following:  # nginx configuration   location /upload {  if ($http_referer !~ "^http://(.+\.)?foo\.com/"){  rewrite .*\.(jpe?g|gif|bmp|png)$ /nohotlink.gif break;  }  }  location ~ \.(php|sql|php3|php4|phtml|pl|py|jsp|asp|htm|shtml|sh|cgi)$ {  deny all;  }   And for the third and final file I have created a file in /etc/nginx/includes names small.access. The contents of this file are as follows:  # nginx configuration   location /upload/small {  }   In the server block configuration file I have:   location / {               try_files $uri $uri/ /index.php;               include /etc/nginx/includes/root.access;      }   location /upload {               include /etc/nginx/includes/upload.access;      }   location /upload/small {               include /etc/nginx/includes/small.access;      }   Now with this configuration when trying the site I receive 403 errors. Nginx error log reports:  [error] 18156#0: *7 access forbidden by rule, client: 111.**.**.**, server: foo.com, request: "POST /upload.php HTTP/1.1", host: "foo.com", referrer: "http://foo.com/"   Now under apache everything works no problems. But I can not see why I am getting 403 errors. I am also worried that the rewrite rules as I have stated them, beyond the 403 error will not function properly at all. Can anyone help me with this? I can not see what is wrong here. "Unable to locate package" while trying to install packages with APT Why is $\frac{\operatorname dy'}{\operatorname dy}$ zero, since $y'$ depends on $y$? I know that $\frac{dy'(x)}{dy}=0$ (where $y'=\frac{dy(x)}{dx}$). The reason explained is that $y'$  does not depend explicitly on $y$. But intuitively, $y'$ depends on $y$, since if you vary $y$ you will modify $y'$. Why is my reasoning wrong (my reasoning sounds like it's related to functional calculus, instead of standard calculus)?  I tried to write  $\frac{dy'(x)}{dy}=\frac{d}{dy}\frac{dy}{dx}=\frac{d}{dx}\frac{dy}{dy}=\frac{d}{dx}1=0$, but this proof doesn't convince me.  I think that other way to see this is saying that if a function is of the form $f(y)$, it will not dependend on the variable $y'$.  But the same way you write $f(y)=y^2$, you could write $f(y)=\frac{d}{dx}y$, which clearly depends on $y'$. So I don't know if there are some types of operations which are restricted (for example, taking limits):  Note: The problem raises in the context of Classical Mechanics, where: $\frac{\partial L(\dot{x},t)}{\partial x}=0$. I have a Godox X2Tc and a Godox X1Rc. I want to control my Canon Speedlite 430 EXII. (I also have a Godox V1, which is a beautiful thing!) I have the Canon Speedlite attached to the Godox receiver, so it should fire. It just wont! How do I set it up correctly so the receiver makes the Canon Speedlite fire?  Update: Michael C answered this question. I had the ID numbers set differently on the transmitter and receiver. I made them the same and now it all works. Perfect! Thanks Michael!!