How to use the command "dot" (with examples)
The “dot” command is a command-line tool for rendering an image of a linear directed network graph from a Graphviz file. It offers a variety of layouts, including dot, neato, twopi, circo, fdp, sfdp, osage, and patchwork. More information about the command can be found at https://graphviz.org/doc/info/command.html .
Use case 1: Render a png image with a filename based on the input filename and output format (uppercase -O):
Code:
dot -T png -O path/to/input.gv
Motivation: This use case is useful when you want to render a png image of the graph from the Graphviz file with the same name as the input file.
Explanation:
dot: The command itself.-T png: Specifies the output format aspng.-O: Indicates that the output filename should be based on the input filename.path/to/input.gv: The path and filename of the Graphviz file to be rendered.
Example output: A png image of the graph will be generated and saved with the same name as the input file at the specified path.
Use case 2: Render an svg image with the specified output filename (lowercase -o):
Code:
dot -T svg -o path/to/image.svg path/to/input.gv
Motivation: If you need an svg image of the graph, this use case allows you to specify the output filename for the image.
Explanation:
dot: The command itself.-T svg: Sets the output format to be svg.-o: Specifies the output filename.path/to/image.svg: The desired path and filename for the svg image.path/to/input.gv: The path and filename of the Graphviz file to be rendered.
Example output: An svg image of the graph will be generated and saved with the specified filename at the specified path.
Use case 3: Render the output in ps, pdf, svg, fig, png, gif, jpg, json, or dot format:
Code:
dot -T format -O path/to/input.gv
Motivation: If you want to render the output in a specific format other than png or svg, you can use this use case. It allows you to choose from a variety of formats, including ps, pdf, fig, gif, jpg, json, and dot.
Explanation:
dot: The command itself.-T format: Specifies the desired output format, such as ps, pdf, svg, fig, png, gif, jpg, json, or dot.-O: Indicates that the output filename should be based on the input filename.path/to/input.gv: The path and filename of the Graphviz file to be rendered.
Example output: The graph will be rendered in the specified format (ps, pdf, svg, fig, png, gif, jpg, json, or dot) and saved with a filename based on the input filename.
Use case 4: Render a gif image using stdin and stdout:
Code:
echo "digraph {this -> that} " | dot -T gif > path/to/image.gif
Motivation: This use case allows you to render a gif image of the graph using the provided input directly from stdin and save it to a specified path and filename.
Explanation:
echo "digraph {this -> that} ": Generates the input graph in the DOT language using echo.|: Pipes the output of the previous command (echo) to the input of the dot command.dot: The command itself.-T gif: Specifies the output format as gif.> path/to/image.gif: Redirects the output of the dot command to the specified path and filename for the gif image.
Example output: A gif image of the graph specified in the DOT language will be generated and saved at the specified path and filename.
Use case 5: Display help:
Code:
dot -?
Motivation: If you need assistance or want to learn more about the available options and command usage, this use case displays the help information for the dot command.
Explanation:
dot: The command itself.-?: Displays the help information for the dot command.
Example output: The help information for the dot command will be displayed, providing details about the available options and command usage.
Conclusion:
The “dot” command is a versatile tool for rendering images of linear directed network graphs from Graphviz files. It offers various output formats and options to customize the rendering process. By understanding and utilizing the different use cases, you can effectively use the “dot” command to generate high-quality graph visualizations.
