How to use the command 'gvpack' (with examples)

The ‘gvpack’ command is a part of the Graphviz suite of tools and is used to combine several graph layouts that already have layout information. It provides various options to control how the layouts are combined.

Use case 1: Combine several graph layouts (that already have layout information)

Code:

gvpack path/to/layout1.gv path/to/layout2.gv ... > path/to/output.gv

Motivation: This use case is useful when you want to merge multiple graph layouts into a single layout file.

Explanation: The command takes multiple input layout files (.gv files) as arguments and combines them into a single layout. The output is redirected to the specified output file (path/to/output.gv).

Example output: The combined layout of the input graphs will be saved in the output.gv file.

Use case 2: Combine several graph layouts at the graph level, keeping graphs separate

Code:

gvpack -g path/to/layout1.gv path/to/layout2.gv ... > path/to/output.gv

Motivation: This use case is useful when you have multiple graphs in each layout file and want to combine the graphs at the layout level while keeping them separate.

Explanation: The -g option tells the command to combine the graphs within each input layout file. The resulting combined layout will have separate subgraphs for each input layout’s graphs.

Example output: The combined layout will contain separate subgraphs for each input layout’s graphs.

Use case 3: Combine several graph layouts at the node level, ignoring clusters

Code:

gvpack -n path/to/layout1.gv path/to/layout2.gv ... > path/to/output.gv

Motivation: This use case is useful when you want to combine the graphs at the node level, ignoring clusters defined in the input layout files.

Explanation: The -n option tells the command to combine the graphs at the node level. It ignores clusters defined in the input layout files and focuses only on combining individual nodes.

Example output: The combined layout will have all the nodes from the input layouts merged together while ignoring any clusters.

Use case 4: Combine several graph layouts without packing

Code:

gvpack -u path/to/layout1.gv path/to/layout2.gv ... > path/to/output.gv

Motivation: This use case is useful when you want to combine several graph layouts without the packing algorithm, which can affect the graph placements.

Explanation: The -u option tells the command to combine the layouts without applying the packing algorithm. The resulting combined layout will maintain the original node and edge placements.

Example output: The combined layout will have the nodes and edges from the input layouts merged together without any changes in their original placements.

Use case 5: Display help for ‘gvpack’

Code:

gvpack -?

Motivation: This use case is useful when you need help with the ‘gvpack’ command and want to access the command’s documentation.

Explanation: The -? option is used to display the help message and documentation for the ‘gvpack’ command.

Example output: The command will output the help message and documentation, providing information on how to use the ‘gvpack’ command effectively.

Conclusion

The ‘gvpack’ command is a versatile tool for combining graph layouts that already have layout information. It allows you to merge layouts at different levels, ignore clusters, and even combine layouts without packing. Understanding these various use cases will help you make the most of the ‘gvpack’ command and create comprehensive visualizations with Graphviz.