NAME¶

gv_perl - graph manipulation in perl

SYNOPSIS¶

#!/usr/bin/perl use gv;

USAGE¶

INTRODUCTION¶

gv_perl is a dynamically loaded extension for perl that provides access to the graph facilities of graphviz.

COMMANDS¶

New graphs

 

New empty graph

 

graph_handle gv::graph (name);

 

graph_handle gv::digraph (name);

 

graph_handle gv::strictgraph (name);

 

graph_handle gv::strictdigraph (name);

 

New graph from a dot-syntax string or file

 

graph_handle gv::readstring (string);

 

graph_handle gv::read (string filename);

 

graph_handle gv::read (channel);

 

Add new subgraph to existing graph

 

graph_handle gv::graph (graph_handle, name);

 

New nodes

 

Add new node to existing graph

 

node_handle gv::node (graph_handle, name);

 

New edges

 

Add new edge between existing nodes

 

edge_handle gv::edge (tail_node_handle, head_node_handle);

 

Add a new edge between an existing tail node, and a named head node which will be induced in the graph if it doesn't already exist

 

edge_handle gv::edge (tail_node_handle, head_name);

 

Add a new edge between an existing head node, and a named tail node which will be induced in the graph if it doesn't already exist

 

edge_handle gv::edge (tail_name, head_node_handle);

 

Add a new edge between named tail and head nodes which will be induced in the graph if they don't already exist

 

edge_handle gv::edge (graph_handle, tail_name, head_name);

 

Setting attribute values

 

Set value of named attribute of graph/node/edge - creating attribute if necessary

 

string gv::setv (graph_handle, attr_name, attr_value);

 

string gv::setv (node_handle, attr_name, attr_value);

 

string gv::setv (edge_handle, attr_name, attr_value);

 

Set value of existing attribute of graph/node/edge (using attribute handle)

 

string gv::setv (graph_handle, attr_handle, attr_value);

 

string gv::setv (node_handle, attr_handle, attr_value);

 

string gv::setv (edge_handle, attr_handle, attr_value);

 

Getting attribute values

 

Get value of named attribute of graph/node/edge

 

string gv::getv (graph_handle, attr_name);

 

string gv::getv (node_handle, attr_name);

 

string gv::getv (edge_handle, attr_name);

 

Get value of attribute of graph/node/edge (using attribute handle)

 

string gv::getv (graph_handle, attr_handle);

 

string gv::getv (node_handle, attr_handle);

 

string gv::getv (edge_handle, attr_handle);

 

Obtain names from handles

 

string gv::nameof (graph_handle);

 

string gv::nameof (node_handle);

 

string gv::nameof (attr_handle);

 

Find handles from names

 

graph_handle gv::findsubg (graph_handle, name);

 

node_handle gv::findnode (graph_handle, name);

 

edge_handle gv::findedge (tail_node_handle, head_node_handle);

 

attribute_handle gv::findattr (graph_handle, name);

 

attribute_handle gv::findattr (node_handle, name);

 

attribute_handle gv::findattr (edge_handle, name);

 

Misc graph navigators returning handles

 

node_handle gv::headof (edge_handle);

 

node_handle gv::tailof (edge_handle);

 

graph_handle gv::graphof (graph_handle);

 

graph_handle gv::graphof (edge_handle);

 

graph_handle gv::graphof (node_handle);

 

graph_handle gv::rootof (graph_handle);

 

Obtain handles of proto node/edge for setting default attribute values

 

node_handle gv::protonode (graph_handle);

 

edge_handle gv::protoedge (graph_handle);

 

Iterators

 

Iteration termination tests

 

bool gv::ok (graph_handle);

 

bool gv::ok (node_handle);

 

bool gv::ok (edge_handle);

 

bool gv::ok (attr_handle);

 

Iterate over subgraphs of a graph

 

graph_handle gv::firstsubg (graph_handle);

 

graph_handle gv::nextsubg (graph_handle, subgraph_handle);

 

Iterate over supergraphs of a graph (obscure and rarely useful)

 

graph_handle gv::firstsupg (graph_handle);

 

graph_handle gv::nextsupg (graph_handle, subgraph_handle);

 

Iterate over edges of a graph

 

edge_handle gv::firstedge (graph_handle);

 

edge_handle gv::nextedge (graph_handle, edge_handle);

 

Iterate over outedges of a graph

 

edge_handle gv::firstout (graph_handle);

 

edge_handle gv::nextout (graph_handle, edge_handle);

 

Iterate over edges of a node

 

edge_handle gv::firstedge (node_handle);

 

edge_handle gv::nextedge (node_handle, edge_handle);

 

Iterate over out-edges of a node

 

edge_handle gv::firstout (node_handle);

 

edge_handle gv::nextout (node_handle, edge_handle);

 

Iterate over head nodes reachable from out-edges of a node

 

node_handle gv::firsthead (node_handle);

 

node_handle gv::nexthead (node_handle, head_node_handle);

 

Iterate over in-edges of a graph

 

edge_handle gv::firstin (graph_handle);

 

edge_handle gv::nextin (node_handle, edge_handle);

 

Iterate over in-edges of a node

 

edge_handle gv::firstin (node_handle);

 

edge_handle gv::nextin (graph_handle, edge_handle);

 

Iterate over tail nodes reachable from in-edges of a node

 

node_handle gv::firsttail (node_handle);

 

node_handle gv::nexttail (node_handle, tail_node_handle);

 

Iterate over nodes of a graph

 

node_handle gv::firstnode (graph_handle);

 

node_handle gv::nextnode (graph_handle, node_handle);

 

Iterate over nodes of an edge

 

node_handle gv::firstnode (edge_handle);

 

node_handle gv::nextnode (edge_handle, node_handle);

 

Iterate over attributes of a graph

 

attribute_handle gv::firstattr (graph_handle);

 

attribute_handle gv::nextattr (graph_handle, attr_handle);

 

Iterate over attributes of an edge

 

attribute_handle gv::firstattr (edge_handle);

 

attribute_handle gv::nextattr (edge_handle, attr_handle);

 

Iterate over attributes of a node

 

attribute_handle gv::firstattr (node_handle);

 

attribute_handle gv::nextattr (node_handle, attr_handle);

 

Remove graph objects

 

bool gv::rm (graph_handle);

 

bool gv::rm (node_handle);

 

bool gv::rm (edge_handle);

 

Layout

 

Annotate a graph with layout attributes and values using a specific layout engine

 

bool gv::layout (graph_handle, string engine);

 

Render

 

Render a layout into attributes of the graph

 

bool gv::render (graph_handle);

 

Render a layout to stdout

 

bool gv::render (graph_handle, string format);

 

Render to an open file

 

bool gv::render (graph_handle, string format, channel fout);

 

Render a layout to an unopened file by name

 

bool gv::render (graph_handle, string format, string filename);

 

Render to a string result

 

string gv::renderresult (graph_handle ing, string format);

 

gv::renderresult (graph_handle, string format, string outdata);

 

Render to an open channel

 

bool gv::renderchannel (graph_handle, string format, string channelname);

 

Render a layout to a malloc'ed string, to be free'd by the caller

 

(deprecated - too easy to leak memory)

 

(still needed for "eval [gv::renderdata $G tk]" )

 

string gv::renderdata (graph_handle, string format);

 

Writing graph back to file

 

bool gv::write (graph_handle, string filename);

 

bool gv::write (graph_handle, channel);

 

KEYWORDS¶

graph, dot, neato, fdp, circo, twopi, perl.