fastpath 1.1.2

A package for finding the best path through a network graph

Introduction

Fastpath is a fast and lightweight tool for finding the shortest path in a weighted graph. As input it only needs the starting node, the ending node, and the weights of each node to node edge. For versatility it uses the Bellman-Ford algorithm, which allows for negative weights. Future version will incorporate the Dijkstra algorithm to speed up runtimes on graphs that do not contain negative edges. To install fastpath,

git clone [e-mail]:deprekate/fastpath.git
cd fastpath; make

The only library dependency for fastpath is uthash (which is included). The fastpathz has the extra dependency of mini-gmp (which is included).

Fastpath Example

Run on included sample data:

fastpath --source a --target e < edges.txt 

Output is the path of nodes, and should look like

a
c
d
e

The structure of the graph looks like:

a ─────▶ b ◀───── f
│        │
│        │
▼        ▼
c ─────▶ d ─────▶ e

• Strings can be used for the nodes, and the weights can be positive or negative long double numbers. The weights can even be in the form of scientific shorthand (1.6E+9).

Python Example

FastPath is now available as a pypi.org package, and is installable by simply using pip

pip install fastpath 

To use in your python code, first import the module, write edges to the graph, and then provide a beginning node (source) and an end node (target)

import fastpath as fp

f = open("edges.txt", "r")
for line in f:
        ret = fp.add_edge(line)

for edge in fp.get_path(source="a", target="e"):
        print(edge)

Output is the path of nodes, and should look like

$ python example.py 
a
c
d
e