Documentation
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Overview ¶
Command contour draws one field three ways, off one colour scale.
It is the example for the thing the contour exists to make possible: a plan and a shape that agree. The flat chart is where a reader takes a number off — "the 3 dB line runs here" — and the surface is where they see what the numbers are doing; the contours on its floor are the same lines as the flat chart's, because both come out of one call to stat.Contour over one lattice.
One ramp, not two like it ¶
The three pictures share a single scale.ColorScale, pinned with scale.ColorDomain. That is the point of the example and it is easy to get wrong: two scale.Sequential values over one column look identical and are two domains that agree by luck, so the same colour means two different numbers the moment either chart is drawn over a subset, a filter or a live window.
Pinning it also makes the outermost isoline the end of the bar rather than something short of it, because the levels are derived from the same pair.
go run ./examples/contour
Source Files