Load a graph from the graph database for testing graph isomorphism.
This function downloads a graph from a database created for the evaluation of graph isomorphism testing algothitms.
graph.graphdb (url = NULL, prefix = "iso", type = "r001", nodes = NULL, pair = "A", which = 0, base = "http://cneurocvs.rmki.kfki.hu/graphdb/gzip", compressed = TRUE, directed = TRUE)
- If not
NULLit is a complete URL with the file to import.
- Gives the prefix. See details below. Possible values:
- Gives the graph type identifier. See details
below. Possible values:
- The number of vertices in the graph.
- Specifies which graph of the pair to read. Possible
- Gives the number of the graph to read. For every graph type there are a number of actual graphs in the database. This argument specifies which one to read.
- The base address of the database. See details below.
- Logical constant, if TRUE than the file is expected
to be compressed by gzip. If
suffix is added to the filename.
- Logical constant, whether to create a directed graph.
graph.graphdb reads a graph from the graph database from an FTP
or HTTP server or from a local copy. It has two modes of operation:
url argument is specified then it should the complete
path to a local or remote graph database file. In this case
we simply call
read.graph with the proper arguments to
read the file.
NULL, and this is the default, then the
filename is assembled from the
See the documentation for the graph database at
- A new graph object.
M. De Santo, P. Foggia, C. Sansone, M. Vento: A large database of graphs and its use for benchmarking graph isomorphism algorithms, Pattern Recognition Letters, Volume 24, Issue 8 (May 2003)
g <- graph.graphdb(prefix="iso", type="r001", nodes=20, pair="A", which=10, compressed=TRUE) g2 <- graph.graphdb(prefix="iso", type="r001", nodes=20, pair="B", which=10, compressed=TRUE) graph.isomorphic.vf2(g, g2)g3 <- graph.graphdb(url="http://cneurocvs.rmki.kfki.hu/graphdb/gzip/iso/bvg/b06m/iso_b06m_m200.A09.gz")