graph

iPhone Facebook Graph API library

Is there an library for the iPhone using the new Facebook Graph API yet? ...

Second min cost spanning tree.

Hello. I'm writing an algorithm for finding the second min cost spanning tree. my idea was as follows: Use kruskals to find lowest MST. Delete the lowest cost edge of the MST. Run kruskals again on the entire graph. return the new MST. My question is: Will this work? Is there a better way perhaps to do this? ...

Boost graph: Apply algorithms considering a specific edge subset.

Hi, I've got a huge graph with typed edge (i.e. edge with a type property). Say typedef adjacency_list<vecS, vecS, vertex_prop, edge_prop> Graph; The "type" of the edge is a member of edge_prop and has a value in {A,B,C,D}, I'd like to run the breadth first search algorithm considering only edges of type A or B. How would you do ...

Do any web graphing or charting libraries have support for error bars?

I have been looking for a graphing library to use in an upcoming web application, but I have two requirements that have been tripping me up: Ability to save the graph as an image. Show error bars on the points of line charts as well as bar charts. I have found solutions to #1 by using flash charts or even the Google Chart API. Howeve...

Using the Facebook Graph APIs PHP library

I am using the PHP library for the Graph API (http://github.com/facebook/php-sdk) but am a bit confused about how it is all working (or not). I just want to authenticate the user and get the user ID back. What I really want to know is what to do once the user has logged in to Facebook and returned to my site. There is data called 'sessi...

Python: x-y-plot with matplotlib

I want to plot some data. The first column contains the x-data. But matplotlib doesnt plot this. Where is my mistake? #fresnel formula import numpy as np from numpy import cos from scipy import * from pylab import plot, show, ylim, yticks from matplotlib import * from pprint import pprint n1 = 1.0 n2 = 1.5 #alpha, beta, intensity dat...

Looking for a solid and scalable library to render undirected graph.

I'll need to throw in about 400 millions of nodes. Preferable languages are java, php, .net, ruby or python. Anything alse will do the same. :D Any ideas? ...

Bipartite matching in Python

Does anybody know any module in Python that computes the best bipartite matching? I have tried the following two: munkres hungarian However, in my case, I have to deal with non-complete graph (i.e., there might not be an edge between two nodes), and therefore, there might not be a match if the node has no edge. The above two packag...

Api to analyse complex graph

I am looking for an API (preferably in python) that could be used to analyze complex networks. Basically I want to find things like: Average shortest path, Degree distribution Giant Component local clustering coefficient, global clustering coefficient etc.. Thanks ...

How do I pick the control point when using CGContextAddCurveToPoint to make a line graph with curves

I'm making a line graph on the iphone using core graphics and instead of having a jagged chart, I want to smooth it out like in good old math class. What's the formula to pick where to put the control points for CGContextAddCurveToPoint? CGFloat cp2x = (x + x + prevX); CGFloat cp1y = (prevY + prevY + y); CGF...

jfreechart time series chart with events

I am using jfreechart (specially ChartFactory.createTimeSeriesChart()). Is there a way to signal events like Google Finance charts, see the A, B, C etc on the right and in the chart. ...

Graph Tour with Uniform Cost Search in Java

Hi. I'm new to this site, so hopefully you guys don't mind helping a nub. Anyway, I've been asked to write code to find the shortest cost of a graph tour on a particular graph, whose details are read in from file. The graph is shown below: http://img339.imageshack.us/img339/8907/graphr.jpg This is for an Artificial Intelligence class,...

get the userid in facebook graph

hey i am working on facebook iframe application in asp.net c# i succeed to retrive the access_token. now i want to pull for example the user likes but i dont have the user id https://graph.facebook.com/XXXXXX/likes?access_token=... how can i get the userid ? thank you all ...

Explain BFS and DFS in terms of backtracking

Wikipedia about DFS Depth-first search (DFS) is an algorithm for traversing or searching a tree, tree structure, or graph. One starts at the root (selecting some node as the root in the graph case) and explores as far as possible along each branch before backtracking. So is BFS? "an algorithm that choose a starting ...

Stanford Parser - Traversing the typed dependencies graph

Hello! Basically I want to find a path between two NP tokens in the dependencies graph. However, I can't seem to find a good way to do this in the Stanford Parser. Any help? Thank You Very Much ...

Any implementations of graph st-ordering or ear-decomposition?

I'm in the search for an implementation of an ear-decomposition algorithm (http://www.ics.uci.edu/~eppstein/junkyard/euler/ear.html). I examined networkx and didn't find one. Although the algorithm layout is vaguely in my mind, I'd like to see some reference implementation, too. I'm aware of Ulrik Brandes publication on a linear time E...

c# - what is best persistence approach/tool/library for a Directed Graph

Hi, What is best persistence approach/tool/library for a Directed Graph in C#. That is assuming I have a class model for a directed graph (e.g. Nodes & Relationships, or Vertex's and Edge's if you like), what would you recommend regarding persisting to a SQL Database? (or if you wish a 2nd question would be where I don't specify a SQL...

Graph Algorithm To Find All Paths Between N Arbitrary Vertices

I have an graph with the following attributes: Undirected Not weighted Each vertex has a minimum of 2 and maximum of 6 edges connected to it. Vertex count will be < 100 Graph is static and no vertices/edges can be added/removed or edited. I'm looking for paths between a random subset of the vertices (at least 2). The paths should s...

Drawing reflexive edges in State Machines

I have to draw a small finite state machine that has some reflexive transitions (meaning the start and the end state of the transition are equal. The problem is that rendering that in Graphviz has ugly results. digraph finite_state_machine { edge [fontsize=11]; S0 -> S0 [label = "td=1\n-/e2"]; S0 -> S1 [label = "td=3 \n-/e3" ]; S...

Display Graph using Boost Graph Library

Can anyone please tell me that once I've created a graph using Boost Graph library, how can I display that graph? My biggest concern is that the edge weights are coming from an exernal data source over the network. And I need to be able to display the edgeweights live as they get updated. ...