plotly/plotly.rs

Table of Contents

• Introduction
• Basic Usage
  • Exporting a single Interactive Plot
  • Exporting Static Images with plotly_static (Recommended)
  • Exporting Static Images with Kaleido (legacy)
  • Usage Within a WASM Environment
  • Timeseries Downsampling
• Crate Feature Flags
• Contributing
• Code of Conduct
• License

Introduction

A plotting library for Rust powered by Plotly.js.

Documentation and numerous interactive examples are available in the Plotly.rs Book, the examples/ directory and docs.rs.

For changes since the last version, please consult the changelog.

Basic Usage

Add this to your Cargo.toml:

[dependencies]
plotly = "0.14"

Exporting a single Interactive Plot

Any figure can be saved as an HTML file using the Plot.write_html() method. These HTML files can be opened in any web browser to access the fully interactive figure.

use plotly::{Plot, Scatter};

let mut plot = Plot::new();
let trace = Scatter::new(vec![0, 1, 2], vec![2, 1, 0]);
plot.add_trace(trace);

plot.write_html("out.html");

By default, the Plotly JavaScript library and some MathJax components will always be included via CDN, which results in smaller file-size, but slightly slower first load as the JavaScript libraries have to be downloaded first. Alternatively, to embed the JavaScript libraries (several megabytes in size) directly into the HTML file, plotly-rs must be compiled with the feature flag plotly_embed_js. With this feature flag the Plotly and MathJax JavaScript libraries are directly embedded in the generated HTML file. It is still possible to use the CDN version, by using the use_cdn_js method.

// <-- Create a `Plot` -->

plot.use_cdn_js();
plot.write_html("out.html");

If you only want to view the plot in the browser quickly, use the Plot.show() method.

// <-- Create a `Plot` -->

plot.show(); // The default web browser will open, displaying an interactive plot

Exporting Static Images with plotly_static (Recommended)

The recommended way to export static images is using the plotly_static backend, which uses a headless browser via WebDriver (Chrome or Firefox) for rendering. This is available via the static_export_default feature:

[dependencies]
plotly = { version = "0.14", features = ["static_export_default"] }

This supports PNG, JPEG, WEBP, SVG, and PDF formats:

use plotly::{Plot, Scatter,ImageFormat};

let mut plot = Plot::new();
plot.add_trace(Scatter::new(vec![0, 1, 2], vec![2, 1, 0]));

plot.write_image("out.png", ImageFormat::PNG, 800, 600, 1.0)?;
plot.write_image("out.svg", ImageFormat::SVG, 800, 600, 1.0)?;
let base64_data = plot.to_base64(ImageFormat::PNG, 800, 600, 1.0)?;
let svg_string = plot.to_svg(800, 600, 1.0)?;

Note: This feature requires a WebDriver-compatible browser (Chrome or Firefox) as well as a Webdriver (chromedriver/geckodriver) to be available on the system.

The above example uses the legacy API that is backwards compatible with the Kaleido API. However, for more efficient workflows a StaticExporter object can be built and reused between calls to write_image.

More specifically, enabling any of the plotly features static_export_chromedriver, static_export_geckodriver, or static_export_default gives access to both the synchronous StaticExporter and the asynchronous AsyncStaticExporter (available via plotly::plotly_static). For exporter reuse and up-to-date sync/async usage patterns, please see the dedicated example in examples/static_export, which demonstrates both synchronous and asynchronous exporters and how to reuse a single exporter instance across multiple exports.

For further details see plotly_static crate documentation.

Exporting Static Images with Kaleido (legacy)

Enable the kaleido feature and opt in for automatic downloading of the kaleido binaries by doing the following

# Cargo.toml

[dependencies]
plotly = { version = "0.14", features = ["kaleido", "kaleido_download"] }

Alternatively, enable only the kaleido feature and manually install Kaleido.

# Cargo.toml

[dependencies]
plotly = { version = "0.14", features = ["kaleido"] }

With the feature enabled, plots can be saved as any of png, jpeg, webp, svg, pdf and eps. Note that the plot will be a static image, i.e. they will be non-interactive.

Exporting a simple plot looks like this:

use plotly::{ImageFormat, Plot};

let mut plot = Plot::new();
let trace = Scatter::new(vec![0, 1, 2], vec![2, 1, 0]);
plot.add_trace(trace);

plot.write_image("out.png", ImageFormat::PNG, 800, 600, 1.0);

Kaleido external dependency

When developing applications for your host, enabling both kaleido and kaleido_download features will ensure that the kaleido binary is downloaded for your system's architecture at compile time. After download, it is unpacked into a specific path, e.g., on Linux this is /home/USERNAME/.config/kaleido. With these two features enabled, static images can be exported as described in the next section as long as the application runs on the same machine where it has been compiled on.

When the applications developed with plotly.rs are intended for other targets or when the user wants to control where the kaleido binary is installed then Kaleido must be manually downloaded and installed. Setting the environment variable KALEIDO_PATH=/path/installed/kaleido/ will ensure that applications that were built with the kaleido feature enabled can locate the kaleido executable and use it to generate static images.

Kaleido binaries are available on Github release page. It currently supports Linux(x86_64), Windows(x86_64) and MacOS(x86_64/aarch64).

Usage Within a WASM Environment

Plotly.rs can be used with a WASM-based frontend framework. Note that the kaleido and plotly_static static export features are not supported in WASM environments and will throw a compilation error if used.

The needed dependencies are automatically enabled for wasm32 targets at compile time and there is no longer a need for the custom wasm flag in this crate.

First, make sure that you have the Plotly JavaScript library in your base HTML template:

 <!-- index.html -->

<!doctype html>
<html lang="en">
    <head>
        <!-- snip -->
        <script src="https://cdn.plot.ly/plotly-2.14.0.min.js"></script>
    </head>
    <!-- snip -->
</html>

A simple Plot component would look as follows, using Yew as an example frontend framework:

use plotly::{Plot, Scatter};
use yew::prelude::*;

#[function_component(PlotComponent)]
pub fn plot_component() -> Html {
    let p = yew_hooks::use_async::<_, _, ()>({
        let id = "plot-div";
        let mut plot = Plot::new();
        let trace = Scatter::new(vec![0, 1, 2], vec![2, 1, 0]);
        plot.add_trace(trace);

        async move {
            plotly::bindings::new_plot(id, &plot).await;
            Ok(())
        }
    });


    use_effect_with((), move |_| {
        p.run();
        || ()
    });


    html! {
        <div id="plot-div"></div>
    }
}

Timeseries Downsampling

In situations where the number of points of a timeseries is extremely large, generating a plot and visualizing it using plotly will be slow or not possible.

For such cases, it is ideal to use a downsampling method that preserves the visual characteristics of the timeseries. One such method is to use the Largest Triangle Three Bucket (LTTB) method. The MinMaxLTTB or classical LTTB method can be used to downsample the timeseries prior to generating the static HTML plots. An example of how this can be achieved can be found in examples/downsampling directory using the minmaxlttb-rs crate.

Crate Feature Flags

The following feature flags are available:

static_export_default

Since version 0.13.0 support for exporting to static images is based on using a new crate called plotly_static that uses WebDriver and browser automation for static export functionality.

This feature flag automatically enables the usage of the plotly_static dependency as well as the chromedriver and webdriver_download features of that crate. For more details about these feature flags, refer to the plotly_static documentation.

The other related features allow controlling other aspects of the plotly_static crate

• static_export_chromedriver
• static_export_geckodriver
• static_export_wd_download

plotly_image

Adds trait implementations so that image::RgbImage and image::RgbaImage can be used more directly with the plotly::Image trace.

plotly_ndarray

Adds support for creating plots directly using ndarray types.

plotly_embed_js

By default, the CDN version of plotly.js is used in the library and in the generated HTML files. This feature can be used to opt in for embedding plotly.min.js in the generated HTML files. The benefit is that the plot will load faster in the browser.

However, there are two downsides of using this feature flag, one is that the resulting html will be much larger, as a copy of the plotly.min.js library is embedded in each HTML file. The second, more relevant, is that a copy of the plotly.min.js library needs to be compiled in the plotly-rs library itself which increases the size by approx 3.5 Mb.

When the feature is enabled, users can still opt in for the CDN version by using the method use_cdn_js.

Note that when using Plot::to_inline_html(), it is assumed that the plotly.js library is already in scope within the HTML file, so enabling this feature flag will have no effect.

kaleido (legacy)

Adds plot save functionality to the following formats: png, jpeg, webp, svg, pdf and eps.

Requires Kaleido to have been previously installed on the host machine. See the following feature flag and Kaleido external dependency.

kaleido_download (legacy)

Enable download and install of Kaleido binary at build time from Kaleido releases on the host machine. See Kaleido external dependency for more details.

Contributing

• If you've spotted a bug or would like to see a new feature, please submit an issue on the issue tracker.

• Pull requests are welcome, see the contributing guide for more information.

Code of Conduct

See the Code of Conduct for more information.

License

Plotly.rs is distributed under the terms of the MIT license, see LICENSE.