The graph file formats include an adjacency graph format, an edge graph format, and a weighted edge graph format. All formats are ascii and entries are delimited by any consecutive sequence of delimiter characters: tab, space, line feed (ascii 0x0A), and carriage return (ascii 0x0D). Files can start and end with delimiters, which are ignored. Throughout the description n refers to the number of vertices and m to the number of edges in a graph.
The adjacency graph format starts with a sequence of offsets one for each vertex, followed by a sequence of directed edges ordered by their source vertex. The offset for a vertex i refers to the location of the start of a contiguous block of out edges for vertex i in the sequence of edges. The block continues until the offset of the next vertex, or the end if i is the last vertex. All vertices and offsets are 0 based and represented in decimal. The specific format is as follows:
The edge graph format consists of a sequence of edges/arcs each being a pair of integers. The format can either be interpreted as a directed graph or an undirected graphs depending on the application. Vertices are assumed to start at 0. The specific format is as follows:
EdgeArraywhere <si> and <ti> refer to the two endpoints of the undirected edge i, or the source and target of a directed edge (arc) i.
The weighted edge graph format is the same as the edge graph format but includes double precision floating point weights. The specific format is as follows:
WeightedEdgeArraywhere <wi> is the weight of edge i. The weight can either be in decimal or exponential notation.
<s0> <t0> <w0>
<s1> <t1> <w1>
<s(n-1)> <t(n-1)> <w(n-1)>
This project has been funded by the following sources:
Intel Labs Academic Research Office for the Parallel Algorithms for Non-Numeric Computing Program,
National Science Foundation, and