You will find [http://**graphdrawing.org**/][1] and [**this tutorial**][3], by **Roberto Tamassia**, professor at Brown University, quite helpful.

I like a lot Force-Directed Techniques (pp. 66-72 in the tutorial) like the **Spring Embedder**. 

You assume there is a spring or other force between any two adjacent nodes and let nature (simulation) do the work :)


  [1]: http://graphdrawing.org/index.html
  [2]: http://graphdrawing.org/literature/gd-constraints.pdf

  [3]: http://cs.brown.edu/people/rtamassi/papers/gd-tutorial/gd-constraints.pdf

I would suggest that you take a look at at [graphviz](http://www.graphviz.org/theory/). The `dot` program can take a specification of a graph and generate an image of the network for you somewhat &quot;cleanly&quot;. I&#39;ve linked to the &quot;theory&quot; page that gives you some links that might be relevant if you&#39;re interested in the theoretical background. The library and tools themselves are mature enough if you simply want a solution to a problem with layout that you&#39;re facing.

Also [JGraph][1] if you want the layouts in Java (I work on the project).


  [1]: http://www.jgraph.com/jgraph.html

I would say as Noufal Ibrahim, but you could also look more precisely at the C API of the [graphviz][1] project. It includes a lib to build your graph ([libgraph.pdf][2]) with all the nodes and edges, and a lib to layout the graph ([libgvc.pdf][3]) (just compute each nodes position), so you can then display it in your own UI for example.


  [1]: http://www.graphviz.org/Documentation.php
  [2]: http://www.graphviz.org/pdf/graph.3.pdf
  [3]: http://www.graphviz.org/pdf/gvc.3.pdf

A good visual guide how the most popular layouts actually look: follow the [link](http://mindfusion.eu/graph-layout.html)

What is the difference between `CurrentCulture`, `InvariantCulture`, `CurrentUICulture` and `InstalledUICulture` from `System.Globalization.CultureInfo`?

Difference between CurrentCulture, InvariantCulture, CurrentUICulture and InstalledUICulture

I have a table filled with a lot of rows and I need to select all the rows that are less than a year old till now.

The table (called `orders`) has a `DateTime` column named `order_date`, that&#39;s the field that determines when the order was placed. 

**How can I select all the records that have an `order_date` between now and a full year ago?**

Selecting all records from one year ago till now

To simplify the problem, I have a graph that contains nodes and edges which are on a 2D plane.

What I want to be able to do is click a button and it make the automatically layout the graph to look clean. By that I mean minimal crossing of edges, nice space between nodes, maybe even represent the graph scale (weighted edges).

I know this is completely subjective of what is a clean looking graph, but does anyone know of an algorithm to start with, rather than reinventing the wheel?

Thanks.

Graph auto-layout algorithm

To simplify the problem, I have a graph that contains nodes and edges which are on a 2D plane.
What I want to be able to do is click a button and it make the automatically layout the graph to look clean. By that I mean minimal crossing of edges, nice space between nodes, maybe even represent the graph scale (weighted edges).
I know this is completely subjective of what is a clean looking graph, but does anyone know of an algorithm to start with, rather than reinventing the wheel?
Thanks.

Given a database of places with Latitude + Longitude locations, such as 40.8120390, -73.4889650, how would I find all locations within a given distance of a specific location?

It doesn&#39;t seem very efficient to select all locations from the DB and then go through them one by one, getting the distance from the starting location to see if they are within the specified distance. Is there a good way to narrow down the initially selected locations from the DB? Once I have (or don&#39;t?) a narrowed down set of locations, do I still go through them one by one to check the distance, or is there a better way?

The language I do this in doesn&#39;t really matter. Thanks!

Algorithm to find all Latitude Longitude locations within a certain distance from a given Lat Lng location

A 2-way merge is widely studied as a part of Mergesort algorithm.
But I am interested to find out the best way one can perform an N-way merge?

Lets say, I have `N` files which have sorted 1 million integers each.
I have to merge them into 1 single file which will have those 100 million sorted integers.

Please keep in mind that use case for this problem is actually external sorting which is disk based. Therefore, in real scenarios there would be memory limitation as well. So a naive approach of merging 2 files at a time (99 times) won&#39;t work. Lets say we have only a small sliding window of memory available for each array.

I am not sure if there is already a standardized solution to this N-way merge. *(Googling didn&#39;t tell me much)*.

But if you know if a good n-way merge algorithm, please post algo/link.

**Time complexity:** If we greatly increase the number of files (`N`) to be merged, how would that affect the time complexity of your algorithm?

Thanks for your answers.

*I haven&#39;t been asked this anywhere, but I felt this could be an interesting interview question. Therefore tagged.*

Algorithm for N-way merge

Requirement: In an unsorted List, determine if a duplicate exists.  The typical way I would do this is an n-squared nested loop.  I&#39;m wondering how others solve this.  Is there an elegant, high performance method in Linq?  Something generic that takes a lambda or a comparer would be nice. 

C# Determine Duplicate in List

Lets say I have a parabola. Now I also have a bunch of sticks that are all of the same width (yes my drawing skills are amazing!).  How can I stack these sticks within the parabola such that I am minimizing the space it uses as much as possible?  I believe that this falls under the category of [Knapsack problems][1],  but this Wikipedia page doesn&#39;t appear to bring me closer to a real world solution.  Is this a NP-Hard problem?   

In this problem we are trying to minimize the amount of area consumed (eg: Integral),  which includes vertical area.

![enter image description here][2]


  [1]: http://en.wikipedia.org/wiki/List_of_knapsack_problems
  [2]: http://i.stack.imgur.com/XqA0t.jpg

Parabolic knapsack

The book is full of interesting questions, but since I am learning it myself, it would be a great help if I can find solutions to at least some of the questions. 

Anyone knows anything about this? 

Where can I find the solutions to &quot;The Algorithm Design Manual&quot;?

I would like to draw a line right in the middle of a layout and use it as a separator of other items like TextView. Is there a good widget for this.  I don&#39;t really want to use an image as it would be hard to match the other components to it.  And I want it to be relatively positioned as well.  Thanks


Android Drawing Separator/Divider Line in Layout?

I have a layout which has three fields for the entry of three map coordinates.  So far so good.  I&#39;m using android:inputType=&quot;numberDecimal&quot; in the layout.  When entering the field the user gets the numeric keypad.  Still good.  

However, when a negative coordinate needs to be entered, there is no apparent way to do this.

23.2342 works fine.
232.3421 works fine.
-11.23423 can not be entered - there is no way to enter the leading negative sign, or even wrap the coordinate in ().

I&#39;m sure I can go the route of changing this to straight text inputType, and then use a regular expression to validate that what was entered is in fact a numeric coordinate, handle error messaging back to the user, etc.  But I&#39;d rather not go that route.  

I have Googled and Stackoverflowed this question for a couple hours with no luck.  Any suggestions?

Android InputType layout parameter - how to allow negative decimals?

I could not find any docs or examples on how to structure my app to allow different views in the same controller to use completely different layouts and stylesheets.

Our app was scaffolded and we then used nifty-generators to generate views, then added devise for authentication. We have views and controllers for two models: widgets and companies.

I currently have a single layout: layouts/application.html.haml, I don&#39;t see that referenced anywhere so I assume (a rails newbie) that it&#39;s always used by naming convention.

I now need to add a couple of views (for mobile browsers) which have a different stylesheet and layout (for example, no login/logout links in the top right), within the same controllers.

How can that be done?


rails 3, how add a view that does not use same layout as rest of app?

I change the position of a UIView with following codes without changing size of the view.

    CGRect f = aView.frame;
    f.origin.x = 100; // new x
    f.origin.y = 200; // new y
    aView.frame = f;

Is there more simple way to change only the view position?


Simple way to change the position of UIView?

I would like to have 2 separate Layouts in my application. Let&#39;s say one is for the Public section of the website and the other is for the Member side.

For simplicity, let&#39;s say all the logic for each of these sites is wrapped neatly into 2 distinct controllers.

 - PublicController
 - StaffController

And that they each have a corresponding Layout for all the View under each.

 - _PublicLayout.cshtml
 - _StaffLayout.cshtml

How do I use the _ViewStart.cshtml file to specify that all Views / Actions under &quot;Public&quot; use the PublicLayout and everything under &quot;Staff&quot; uses the StaffLayout?


How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?

What is the maximum number of edges in a directed graph with n nodes? Is there any upper bound?

What is the maximum number of edges in a directed graph with n nodes?

How do I export a graph to an .eps format file? I typically export my graphs to a .pdf file (using the &#39;pdf&#39; function), and it works quite well. However, now I have to export to .eps files.

Export a graph to .eps file with R

I was wondering about a quick to write implementation of a graph in c++. I need the data structure to be easy to manipulate and use graph algorithms(such as BFS,DFS, Kruskal, Dijkstra...).
I need this implementation for an algorithms Olympiad, so the easier to write the data structure the better.

Can you suggest such DS(main structs or classes and what will be in them). I know that an Adjacency list and Adjacency matrix are the main possibilities, but I mean a more detailed **code** sample.

For example I thought about this DS last time I had to implement a graph for DFS:

    struct Edge {
      int start;
      int end;
      struct Edge* nextEdge;
    }

and then used a array of size n containing in its i&#39;th place the Edge List(struct Edge) representing the edges starting in the i&#39;th node.

but when trying to DFS on this graph I had to write a 50 line code with about 10 while loops.

What &#39;good&#39; implementations are there?

Graph implementation C++

This question is about toolkits which draw graphs (those things composed of vertices and edges), not generic plots.

The tool must be able to get a set of vertices and edges, calculate their layout, and display them either using the canvas tag, or SVG, that is be compatible with HTML5.

Flash-based tools and java applets are out.

to serve as unified benchmark, please measure and report how long it takes for the toolkit to layout and draw a Barabasi-Albert graph with 100 vertices and 5 edges per node.

This python lybrary shows how to generate it and exports it to many formats:

http://networkx.lanl.gov/tutorial/tutorial.html#graph-generators-and-graph-operations

Please indicate browser and CPU.


What&#39;s the fastest, pure Javascript, Graph visualization toolkit?

I am using HighCharts for a line graph report. In this specific report I have been asked to Customize the colours of each series. The series will always stay the same. So for example:

John series: Blue dashed line
Mary series: Solid Red Line

Does anyone know how to accomplish this?

HighCharts : Is it possible to customize the colors of individual series?

What is the easiest way to swap the order of child nodes?

For example I want childNode[3] to be childNode[4] and vice-versa.

How to swap DOM child nodes in JavaScript?

I&#39;m trying to allow javascript to communicate with a Node.js server. 

**POST request (web browser)**

    var	http = new XMLHttpRequest();
    var params = &quot;text=stuff&quot;;
    http.open(&quot;POST&quot;, &quot;http://someurl.net:8080&quot;, true);
    
    http.setRequestHeader(&quot;Content-type&quot;, &quot;application/x-www-form-urlencoded&quot;);
    http.setRequestHeader(&quot;Content-length&quot;, params.length);
    http.setRequestHeader(&quot;Connection&quot;, &quot;close&quot;);
    
    alert(http.onreadystatechange);
    http.onreadystatechange = function() {
      if (http.readyState == 4 &amp;&amp; http.status == 200) {
        alert(http.responseText);
      }
    }
    
    http.send(params);

Right now the Node.js server code looks like this. Before it was used for GET requests. I&#39;m not sure how to make it work with POST requests.

**Server (Node.js)**

    var server = http.createServer(function (request, response) {
      var queryData = url.parse(request.url, true).query;
    
      if (queryData.text) {
        convert(&#39;engfemale1&#39;, queryData.text, response);
    	response.writeHead(200, {
    	  &#39;Content-Type&#39;: &#39;audio/mp3&#39;, 
    	  &#39;Content-Disposition&#39;: &#39;attachment; filename=&quot;tts.mp3&quot;&#39;
    	});
      } 
      else {
        response.end(&#39;No text to convert.&#39;);
      }
    }).listen(8080);

Thanks in advance for your help.

Node.js server that accepts POST requests

What is the difference (if any) between a node and a vertex? I can&#39;t find the answer after looking at countless sites! Even my book doesn&#39;t specify it so I am kind of lost!

*It is worth mentioning that I am looking for the difference besides the fact that it is called a &#39;vertex&#39; when used in a graph and a &#39;node&#39; when used in a tree.*

What is the difference between a node and a vertex?

The status of nodes is reported as `unknown`

    &quot;conditions&quot;: [
              {
                &quot;type&quot;: &quot;Ready&quot;,
                &quot;status&quot;: &quot;Unknown&quot;,
                &quot;lastHeartbeatTime&quot;: &quot;2015-11-12T06:03:19Z&quot;,
                &quot;lastTransitionTime&quot;: &quot;2015-11-12T06:04:03Z&quot;,
                &quot;reason&quot;: &quot;Kubelet stopped posting node status.&quot;
              }


 whle `kubectl get nodes` return a NOTReady status. What does this imply and how to fix this?

Content Type	Original Author	Original Content on Stackoverflow
Question	Cheetah	View Question on Stackoverflow
Solution 1 - Algorithm	ypercubeᵀᴹ	View Answer on Stackoverflow
Solution 2 - Algorithm	Noufal Ibrahim	View Answer on Stackoverflow
Solution 3 - Algorithm	Frodo Baggins	View Answer on Stackoverflow
Solution 4 - Algorithm	jslap	View Answer on Stackoverflow
Solution 5 - Algorithm	Diana Jobs	View Answer on Stackoverflow

Graph auto-layout algorithm

Algorithm Problem Overview

Algorithm Solutions

Solution 1 - Algorithm

Solution 2 - Algorithm

Solution 3 - Algorithm

Solution 4 - Algorithm

Solution 5 - Algorithm

Selecting all records from one year ago till now

Difference between CurrentCulture, InvariantCulture, CurrentUICulture and InstalledUICulture

Attributions