[ncl-talk] Fwd: clean edges along a satellite orbit

[David Brown]

Hi Laura,

The problem here is that you have 1D data that can only be contoured
using a triangular mesh. The triangular mesh algorithm does not handle
data with concave boundaries very well. It assumes that everything
inside the convex hull of the data extents is part of the data space
and fills it in. Since the triangulation occurs in the projected
space, the projection determines whether there will be concave
boundaries or not. You can get a correct plot, but only by setting up
a projection in such a way as to get non-concave boundaries. I have
modified your script by trial and error to get correct plots for the
first three datasets using an orthographic projection. This is rather
tedious and probably not what you want but I am attaching the modified
script and sample plots so you can see what this looks like. If you
need to use the cylindrical equidistant projection or if you want to
put more than one of these datasets into a single frame you will
probably need to interpolate the data to a regular grid prior to
plotting.

Anyway here is the modified script plus 3 sample output plots.
  -dave
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