mpl-gradients

A lightweight, zero-dependency library to add linear gradient fills to Matplotlib charts. Solves matplotlib/matplotlib#30958.

Features

• Vertical Gradients: Fade from Top to Bottom.
• Horizontal Gradients: Fade from Left to Right.
• Diagonal Gradients: Fade from Corner to Corner.
• Alpha Blending: Correctly handles transparency.

Installation

You can install directly from GitHub:

pip install mpl-gradients

Quick start

import matplotlib.pyplot as plt
from mpl_gradients import LinearGradient

fig, ax = plt.subplots()
ax.bar([0, 1, 2], [10, 20, 15])

# Create a gradient (Top-Left Navy -> Bottom-Right Lime)
gradient = LinearGradient("navy", "lime", direction="diagonal")

# Apply to bars
for bar in ax.containers[0]:
    bar.set_agg_filter(gradient)

plt.show()

Requirements

Python 3.9+

Matplotlib

Numpy

New in v0.2.0: Transparency Support

You can now create gradients that fade to transparent!

By default, gradients preserve the original alpha of the plot (preserve_alpha=True). To create transparent gradients (e.g., Red -> Transparent), set preserve_alpha=False.

from mpl_gradients import LinearGradient

# Create a gradient that fades from Red to Transparent to Green
gradient = LinearGradient.from_colors(
    ["red", "#ffffff00", "green"],
    preserve_alpha=False
)

# Apply it
ax.fill_between(x, y, color="blue").set_agg_filter(gradient)