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Questions tagged [graph]

This "graph" tag refers to a graphical data presentation, e.g. chart or diagram. For the mathematical concept use [graph-theory].

A graph is a visual representation of the relationship between two or more variables. Graphs are especially useful for recognizing broad trends or patterns in large data-sets, and thus are often used for visualising scientific data.

Related tags:

For graphs in discrete mathematics (consisting of nodes/vertices and edges/arcs/relationships which connect pairs of these nodes/vertices), please use . You might also include one of the following tags:

  • for questions on graph-related algorithms.
  • for questions on database technologies for persisting and querying graphs.
28721 questions
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Cycles in family tree software

I am the developer of some family tree software (written in C++ and Qt). I had no problems until one of my customers mailed me a bug report. The problem is that the customer has two children with their own daughter, and, as a result, he can't use my…
Partick Höse
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Generating statistics from Git repository

I'm looking for some good tools/scripts that allow me to generate a few statistics from a git repository. I've seen this feature on some code hosting sites, and they contained information like... commits per author commits per…
BastiBen
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8 answers

Python Graph Library

I'm writing a python application that will make heavy use of a graph data structure. Nothing horribly complex, but I'm thinking some sort of graph/graph-algorithms library would help me out. I've googled around, but I don't find anything that…
cpatrick
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Plotting two variables as lines using ggplot2 on the same graph

A very newbish question, but say I have data like this: test_data <- data.frame( var0 = 100 + c(0, cumsum(runif(49, -20, 20))), var1 = 150 + c(0, cumsum(runif(49, -10, 10))), date = seq(as.Date("2002-01-01"), by="1 month",…
fmark
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Generating a PNG with matplotlib when DISPLAY is undefined

I am trying to use networkx with Python. When I run this program it get this error. Is there anything missing? #!/usr/bin/env python import networkx as nx import matplotlib import matplotlib.pyplot import matplotlib.pyplot as…
krisdigitx
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Good Java graph algorithm library?

Has anyone had good experiences with any Java libraries for Graph algorithms. I've tried JGraph and found it ok, and there are a lot of different ones in google. Are there any that people are actually using successfully in production code or would…
Nick Fortescue
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6 answers

Set Colorbar Range in matplotlib

I have the following code: import matplotlib.pyplot as plt cdict = { 'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)), 'green': ( (0.0, 0.0, 0.0), (0.02, .45, .45), (1., .97, .97)), 'blue' : ( (0.0, 1.0, 1.0), (0.02, .75, .75),…
Paul
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Force R to stop plotting abbreviated axis labels (scientific notation) - e.g. 1e+00

In ggplot2 how can I stop axis labels being abbreviated - e.g. 1e+00, 1e+01 along the x axis once plotted? Ideally, I want to force R to display the actual values which in this case would be 1,10. Any help much appreciated.
JPD
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Command-line Unix ASCII-based charting / plotting tool

Is there a good command-line UNIX charting / graphing / plotting tool out there? I'm looking for something that will plot xy points on an ASCII graph. Just to clarify, I'm looking for something that will output a graph in ASCII (like ascii-art…
bajafresh4life
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How does Dijkstra's Algorithm and A-Star compare?

I was looking at what the guys in the Mario AI Competition have been doing and some of them have built some pretty neat Mario bots utilizing the A* (A-Star) Pathing Algorithm. (Video of Mario A* Bot In Action) My question is, how does A-Star…
KingNestor
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What is better, adjacency lists or adjacency matrices for graph problems in C++?

What is better, adjacency lists or adjacency matrix, for graph problems in C++? What are the advantages and disadvantages of each?
magiix
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5 answers

How to plot multiple functions on the same figure

How can I plot the following 3 functions (i.e. sin, cos and the addition), on the domain t, in the same figure? import numpy as np import matplotlib.pyplot as plt t = np.linspace(0, 2*np.pi, 400) a = np.sin(t) b = np.cos(t) c = a + b
user3277335
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how to draw directed graphs using networkx in python?

I have some nodes coming from a script that I want to map on to a graph. In the below, I want to use Arrow to go from A to D and probably have the edge colored too in (red or something). This is basically, like a path from A to D when all other…
brain storm
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17 answers

Dependency graph of Visual Studio projects

I'm currently migrating a big solution (~70 projects) from VS 2005 + .NET 2.0 to VS 2008 + .NET 3.5. Currently I have VS 2008 + .NET 2.0. The problem is that I need to move projects one by one to new .NET framework ensuring that no .NET 2.0 project…
Migol
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4 answers

Representing graphs (data structure) in Python

How can one neatly represent a graph in Python? (Starting from scratch i.e. no libraries!)What data structure (e.g. dicts/tuples/dict(tuples)) will be fast but also memory efficient?One must be able to do various graph operations on it. As pointed…
shad0w_wa1k3r
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