colormesh

lq.colormesh(x, y, z, map=color.map.viridis, min=auto, max=auto, excess="clamp", norm="linear", interpolation="pixelated", label=none, z-index=2)(source)

Plots a rectangular color mesh, e.g., a heatmap.

#lq.diagram(
  width: 4cm, height: 4cm,
  lq.colormesh(
    lq.linspace(-4, 4, num: 10),
    lq.linspace(-4, 4, num: 10),
    (x, y) => x * y,
    map: color.map.magma
  )
)

When the input x and y coordinate arrays are both evenly spaced, an image is drawn instead of individual rectangles. This reduces the file size and improves rendering in most cases. When either array is not evenly spaced, the entire color mesh is drawn with individual rectangles.

Parameters

x : array

A one-dimensional array of $x$ coordinates.

y : array

A one-dimensional array of $y$ coordinates.

z : array | function

Specifies the $z$ coordinates (height) for all combinations of $x$ and $y$ coordinates. This can either be a

• two-dimensional $m×n$-array where $m$ is the length of colormesh.y and $n$ is the length of colormesh.x (for each $y$ value, a row of $x$ values),
• or a function that takes an x and a y value and returns a corresponding z coordinate. Also see the function mesh that can be used to create such meshes.

For masking, you can use float.nan values to hide individual cells of the color mesh.

map : array | gradient    default: color.map.viridis

A color map in the form of a gradient or an array of colors to sample from.

min : auto | int | float    default: auto

Sets the data value that corresponds to the first color of the color map. If set to auto, it defaults to the minimum $z$ value.

max : auto | int | float    default: auto

Sets the data value that corresponds to the last color of the color map. If set to auto, it defaults to the maximum $z$ value.

excess : "clamp" | "mask"    default: "clamp"

Determines how values outside the range defined by colormesh.min and colormesh.max are handled.

• "clamp": Values below colormesh.min are mapped to the first color of the color map, values above colormesh.max are mapped to the last color.
• "mask": Values outside the range are not drawn and appear transparent.

norm : lq.scale | str | function    default: "linear"

The normalization method used to scale $z$ coordinates to the range $[0,1]$ before mapping them to colors using the color map. This can be a scale, a string that is the identifier of a built-in scale or a function that takes one argument (for example the argument x => calc.log(x) would be equivalent to passing "log"). Note that the function does not actually need to map the values to the interval $[0,1]$. Instead it describes a scaling that is applied before the data set is linearly scaled to the interval $[0,1]$.

interpolation : "pixelated" | "smooth"    default: "pixelated"

Whether to apply smoothing or leave the color mesh pixelated. This is currently only supported when colormesh.x and colormesh.y are evenly spaced.

label : content    default: none

The legend label for this plot. See plot.label.

z-index : int | float    default: 2

Determines the $z$ position of this plot in the order of rendered diagram objects. See plot.z-index.