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

The sfdp command is used to render an image of a scaled force-directed network graph from a graphviz file. It is part of the Graphviz suite of tools and allows users to generate visual representations of graphs.

Use case 1: Render a png image with a filename based on the input filename and output format (uppercase -O)

Code:

sfdp -T png -O path/to/input.gv

Motivation: Sometimes when working with large graph files, it can be helpful to visualize them as images. The sfdp command allows you to generate a PNG image of the graph, which can be easily viewed and shared.

Explanation:

• -T png: Specifies the output format as PNG.
• -O path/to/input.gv: Saves the output with a filename based on the input filename and output format.

Example output: A PNG image of the graph will be generated and saved using the filename input.png in the path/to/ directory.

Use case 2: Render an svg image with the specified output filename (lowercase -o)

Code:

sfdp -T svg -o path/to/image.svg path/to/input.gv

Motivation: SVG images are scalable and can be easily edited using vector graphic editing software. By specifying the output format as SVG, the generated image can be customized and modified as needed.

Explanation:

• -T svg: Specifies the output format as SVG.
• -o path/to/image.svg: Sets the output filename as image.svg.

Example output: An SVG image of the graph will be generated and saved as image.svg in the path/to/ directory.

Use case 3: Render the output in ps, pdf, svg, fig, png, gif, jpg, json, or dot format

Code:

sfdp -T format -O path/to/input.gv

Motivation: The sfdp command supports various output formats, allowing users to choose the format that best suits their needs. This flexibility enables easy integration with different software or platforms that require specific image formats.

Explanation:

• -T format: Specifies the output format, where format can be replaced with any of the supported formats, such as ps, pdf, svg, fig, png, gif, jpg, json, or dot.
• -O path/to/input.gv: Saves the output with a filename based on the input filename and output format.

Example output: A file with the specified format (e.g., input.png for PNG format) will be generated and saved in the path/to/ directory.

Use case 4: Render a gif image using stdin and stdout

Code:

echo "digraph {this -> that} " | sfdp -T gif > path/to/image.gif

Motivation: In some cases, it may be convenient to directly provide the graph definition using standard input instead of reading from a file. By using stdin and stdout, the sfdp command can generate a GIF image of the graph without the need for an intermediate graphviz file.

Explanation:

• echo "digraph {this -> that} ": Provides the graph definition as a string using echo command.
• |: The pipe operator redirects the output from the previous command to the stdin of the next command.
• sfdp -T gif: Specifies the output format as GIF.
• > path/to/image.gif: Redirects the output to the specified filename.

Example output: A GIF image of the graph described by the provided graph definition will be generated and saved as image.gif in the path/to/ directory.

Use case 5: Display help

Code:

sfdp -?

Motivation: When getting started with a new command, it is often helpful to refer to the command’s documentation to understand its usage and available options. The -? option allows you to quickly access the help information for the sfdp command.

Explanation:

• -?: Displays the help information for the sfdp command.

Example output: The help documentation for the sfdp command will be displayed, providing information on how to use the command and the available options.

Conclusion:

The sfdp command is a powerful tool for generating visual representations of scaled force-directed network graphs from graphviz files. By utilizing different options and formats, users can generate images that meet their specific requirements. Whether it’s visualizing large graphs, creating scalable images, or accessing help documentation, the sfdp command provides the necessary functionality.