fig_utils

Utilities for rendering matplotlib figures as HTML.

neutcurve.fig_utils.fig_html(fig, display_method)

Render a large matplotlib figure as a self-contained HTML string.

This function is designed for when you have a very large matplotlib figure (eg, as produced by the plotting functions of neutcurve.curvefits.CurveFits) and you want to put it in an HTML page. For display_method="svg" and "pdf" the figure is placed in a fixed-height scrollable box, so that a figure with many panels does not force the rest of the page arbitrarily far down.

The same figure always gives the same HTML, so a report built from this can be tracked in version control without every run showing a difference.

Requires pillow if you are using display_method="png8"; it is installed with matplotlib in any case.

Args:

fig (matplotlib.figure.Figure)

The figure we want to render.

display_method {“svg”, “pdf”, “png8”}

Render the figure as a SVG, as a PDF, or as a PNG8. In general, rendering as a PNG8 will be the smallest size although also the lowest resolution.

Returns:

str

HTML that can be embedded in a page, or passed to marimo.Html.

Example:

>>> import matplotlib.figure
>>> fig = matplotlib.figure.Figure(figsize=(2, 2))
>>> _ = fig.subplots().plot([0, 1], [0, 1])

The SVG is wrapped in the scrollable box, and is a real SVG rather than an image:

>>> html = fig_html(fig, "svg")
>>> '<div id="svgwrap" style="width:100%;height:80vh;overflow:auto">' in html
True
>>> "<svg" in html
True

The other methods embed the figure as a data URI:

>>> fig_html(fig, "pdf").startswith("<iframe src='data:application/pdf;base64,")
True
>>> fig_html(fig, "png8").startswith('<img src="data:image/png;base64,')
True

Rendering the same figure twice gives the same HTML:

>>> all(fig_html(fig, m) == fig_html(fig, m) for m in ["svg", "pdf", "png8"])
True

Anything else is an error. Note in particular that there is no "inline" method here, as a bare figure has no HTML form; see neutcurve.marimo_utils.display_fig_marimo() for that:

>>> fig_html(fig, "inline")
Traceback (most recent call last):
    ...
ValueError: Invalid display_method='inline', valid methods are 'svg', 'pdf', 'png8'