Frameless Heatmap

A frameless heatmap can be achieved by disabling axis labels and ticks, then setting the margins to 0 so the data area tightly fits the data.

Heatmap.cs

ScottPlot.Plot myPlot = new();

double[,] data = {
    { 1, 2, 3 },
    { 4, 5, 6 },
    { 7, 8, 9 },
};

// add a heatmap to the plot
myPlot.Add.Heatmap(data);

// hide axes on all edges of the figure
myPlot.Layout.Frameless();

// disable padding around the heatmap data
myPlot.Axes.Margins(0, 0);

myPlot.SavePng("demo.png", 400, 300);

Edit on GitHub

This recipe is one of many in the Heatmap category