MatPlotLibNet — matplotlib for .NET

MatPlotLibNet is a charting library for C#, .NET 10 and .NET 8, inspired by matplotlib. It draws 91 chart types and saves them as SVG, PNG, PDF or an animated GIF, straight from your server code. It does not need a JavaScript framework, a WebView or a hosted service.

It has a fluent API and it works with dependency injection. It ships with 148 colormaps, 30 themes, 13 map projections with embedded Natural Earth data, LaTeX-style MathText, text in any script, O(1) streaming (57 of its 59 technical indicators have a streaming form), a control room (Plt.OpsDashboard() — KPI tiles, state timelines, one shared trend window), and an MCP server so an AI agent can draw with it. Charts render natively in Blazor, WPF, MAUI, Avalonia, Uno and ASP.NET Core, inside a Verso notebook cell, and TypeScript clients are there for Angular, React and Vue.

Where this is going

1.29.0 puts shapes on an axes and lets an axis show another unit. A rectangle, a polygon, an arrow, a circle, an ellipse, a wedge and an arc (AddPatch) are placed in data coordinates and bend with the axes they stand on, as matplotlib's patches do: on a log axis a circle bends and a straight edge stays straight. They count in the automatic range, a labelled one has a row in the legend, and they travel through JSON and the MCP server. A top or side axis can show the same values in another unit through a function and its inverse (Link with an AxisTransform: degrees Celsius against Fahrenheit, a frequency against its period), as matplotlib's secondary_xaxis and secondary_yaxis do. The top X axis now follows its own tick locator and scale, a series on it follows a log primary Y axis, a translucent line or text keeps its opacity in the SVG, a figure built with AddSubPlot(rows, cols, index) keeps its cell through JSON, and the MCP server draws a spec that holds shapes, spans or annotations and no series. The three rows that were still to come on the roadmap are done.

1.28.0 draws more of what matplotlib draws. Stairs, VLines, HLines and Triplot join the chart verbs, and a sixth family of verbs (Psd, Csd, Cohere, MagnitudeSpectrum, PhaseSpectrum, AngleSpectrum, Acorr, Xcorr) draws a sampled signal in the frequency domain, and its correlation, with matplotlib's defaults; the twelve bring the chart verbs to thirty-eight. A contour label follows its line, upright and in the line's colour; a figure carries text, a legend and an image of its own (FigText, FigLegend, FigImage), drawn on a figure with no subplot too; and an inset marks the region it zooms into (IndicateZoom). The spectrogram windows each frame once and draws its rows at the frequencies they are, a line that is downsampled keeps its gaps, and a line set to LineStyle.None draws no line. A figure's texts, legend and images and an inset's zoom travel through JSON and the MCP server.

1.27.0 finishes the roadmap. A word cloud, a chord diagram, a ternary plot and a Piper diagram are new charts, a selection in one chart can light the same rows in another, and an animation can be saved as one SVG that steps through its frames. A live chart sends its own gestures, one handler interface receives them, and several viewers of one chart share it by design. The native controls return Home to the first view, the MAUI view reaches the same functions, and the Window

... View full README on GitHub