`colormap` — Set colormaps for images, surfaces, contours, and MATLAB `colormap` workflows.

colormap sets the active color palette for the current plotting context. In RunMat it affects colormap-driven visualizations such as imagesc, surf, surfc, contourf, and related scalar-field plots while remaining scoped to the active axes state.

How `colormap` works in RunMat

Supported colormap names include parula, viridis, plasma, inferno, magma, turbo, jet, hot, cool, spring, summer, autumn, winter, gray, bone, copper, pink, and lines.
Unknown colormap names raise errors rather than silently falling back.
Colormap state composes naturally with colorbar, imagesc, surf, and filled contour plots.
Colormap changes apply to the current axes context in the plotting state model.

Examples

Apply a palette to a scaled image

[X, Y] = meshgrid(linspace(-3, 3, 60), linspace(-3, 3, 60));
A = sin(X) .* cos(Y);
imagesc(A);
colormap('jet');
colorbar;

Compare palettes across subplots

[X, Y] = meshgrid(linspace(-3, 3, 40), linspace(-3, 3, 40));
Z = sin(X) .* cos(Y);
subplot(1, 2, 1);
surf(X, Y, Z);
colormap('parula');
subplot(1, 2, 2);
contourf(X, Y, Z);
colormap('turbo');

FAQ

What colormaps are available?

RunMat ships with: parula, viridis, plasma, inferno, magma, turbo, jet, hot, cool, spring, summer, autumn, winter, gray, bone, copper, pink, and lines. Unknown names raise an error — no silent fallback.

Which colormaps are perceptually uniform?

viridis, plasma, inferno, and magma are designed so that equal steps in data value produce equal perceptual changes in color. Use these for quantitative data where you want the visual contrast to faithfully represent magnitude differences. parula is also a good default. Avoid jet for quantitative work — it introduces false banding.

Can I define a custom colormap?

Not yet — colormap currently accepts named strings only. Custom N×3 RGB matrices are on the roadmap. For now, pick the closest built-in option or combine subplot-level colormaps to get variety across panels.

These functions work well alongside colormap. Each page has runnable examples you can try in the browser.

colorbar, imagesc, image, surf, contourf

More plotting resources

Open-source implementation

Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how colormap works, line by line, in Rust.

View colormap.rs on GitHub
Learn how the runtime works
Found a bug? Open an issue with a minimal reproduction.

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colormap — Set colormaps for images, surfaces, contours, and MATLAB colormap workflows.

How colormap works in RunMat