gv(3perl)
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 an open channel
- bool gv::renderchannel (graph_handle, string format, string channelname);
- Render to a string result
- gv::renderresult (graph_handle, string format, string outdata);
- 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.