What is vega-parser?
The vega-parser npm package is a library for parsing Vega specifications into a format that can be used to generate visualizations. It is part of the Vega ecosystem, which is a set of tools for creating, sharing, and exploring data visualizations. The parser takes a JSON specification and converts it into a dataflow graph that can be rendered by Vega's runtime.
What are vega-parser's main functionalities?
Parsing Vega Specifications
This feature allows you to parse a Vega specification JSON into a dataflow graph. The parsed specification can then be used to generate visualizations.
const vega = require('vega-parser');
const spec = { /* Vega specification JSON */ };
const parsedSpec = vega.parse(spec);
console.log(parsedSpec);
Customizing Parsing Options
This feature allows you to customize the parsing process by providing additional options. These options can control various aspects of the parsing, such as logging and error handling.
const vega = require('vega-parser');
const spec = { /* Vega specification JSON */ };
const options = { /* Custom parsing options */ };
const parsedSpec = vega.parse(spec, options);
console.log(parsedSpec);
Other packages similar to vega-parser
vega-lite
Vega-Lite is a high-level grammar of interactive graphics. It provides a concise JSON syntax for rapidly generating visualizations to support analysis. Compared to vega-parser, Vega-Lite is more user-friendly and easier to use for creating standard visualizations, but it is less flexible for complex custom visualizations.
d3
D3.js is a JavaScript library for producing dynamic, interactive data visualizations in web browsers. It uses HTML, SVG, and CSS. While D3 offers more control and flexibility compared to vega-parser, it requires more effort and expertise to create visualizations from scratch.
plotly.js
Plotly.js is a high-level, declarative charting library. It supports a wide range of chart types and is built on top of D3 and stack.gl. Compared to vega-parser, Plotly.js is more focused on providing ready-to-use chart types and is easier to use for quick visualizations, but it may not offer the same level of customization.
vega-parser
Parse Vega specifications to runtime dataflow descriptions.
API Reference
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vega.parse(specification[, config])
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Parses a Vega JSON specification as input and produces a reactive dataflow graph description for a visualization. The output description uses the format of the vega-runtime module. To create a visualization, use the runtime dataflow description as the input to a Vega View instance.
The optional config object provides visual encoding defaults for marks, scales, axes and legends. Different configuration settings can be used to change choices of layout, color, type faces, font sizes and more to realize different chart themes. For more, see the configuration documentation below or view the source code defining Vega's default configuration.
In addition to passing configuration options to this parse method, Vega JSON specifications may also include a top-level "config"
block specifying configuration properties. Configuration options defined within a Vega JSON file take precedence over those provided to the parse method.
Configuration
The Vega parser accepts a configuration file that defines default settings for a variety of visual encoding choices. Different configuration files can be used to "theme" charts with a customized look and feel. A configuration file is simply a JavaScript object with a set of named properties, grouped by type.
For more information regarding the supported configuration options, please see the Vega config documentation.