This function downloads a graph from a database created for the evaluation of graph isomorphism testing algothitms.
graph_from_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
)
A new graph object.
If not NULL
it is a complete URL with the file to import.
Gives the prefix. See details below. Possible values:
iso
, i2
, si4
, si6
, mcs10
, mcs30
,
mcs50
, mcs70
, mcs90
.
Gives the graph type identifier. See details below. Possible
values: r001
, r005
, r01
, r02
, m2D
,
m2Dr2
, m2Dr4
, m2Dr6
m3D
, m3Dr2
,
m3Dr4
, m3Dr6
, m4D
, m4Dr2
, m4Dr4
,
m4Dr6
, b03
, b03m
, b06
, b06m
, b09
,
b09m
.
The number of vertices in the graph.
Specifies which graph of the pair to read. Possible values:
A
and B
.
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 url
is NULL
then a ‘.gz
’
suffix is added to the filename.
Logical constant, whether to create a directed graph.
g <- graph_from_graphdb(prefix="iso", type="r001", nodes=20, pair="A",
which=10, compressed=TRUE)
g2 <- graph_from_graphdb(prefix="iso", type="r001", nodes=20, pair="B",
which=10, compressed=TRUE)
graph.isomorphic.vf2(g, g2) % should be TRUE
g3 <- graph_from_graphdb(url=paste(sep="/",
"http://cneurocvs.rmki.kfki.hu",
"graphdb/gzip/iso/bvg/b06m",
"iso_b06m_m200.A09.gz"))
Gabor Csardi csardi.gabor@gmail.com
graph_from_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:
If the 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.
If url
is NULL
, and this is the default, then the filename is
assembled from the base
, prefix
, type
, nodes
,
pair
and which
arguments.
Unfortunately the original graph database homepage is now defunct, but see its old version at http://web.archive.org/web/20090215182331/http://amalfi.dis.unina.it/graph/db/doc/graphdbat.html for the actual format of a graph database file and other information.
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)
read_graph
, graph.isomorphic.vf2