Mapping (pscoast) in polar coordinates

Q&A
1

Hi all,
I am new to this forum, not sure if this is where I ask for new features but here it is:
Can we use pscoast with a -JP (polar coordinates) map projection? We’d give the lat, lon of the center point and the great-circle distance and azimuth to all other points become the radius and angle in polar coordinates. It would be useful to plot maps this way so we can overlay calculations that were made as a function of great-circle distance and azimuth (such as wavefronts).
Suzan
PS I know that I can convert my “polar coordinates” to map coordinates and use any other map projection. My Q is about the reverse.

2

Because -JP expects aximuths and radial distance we cannot feed it coastlines. However, I think this is how it might work:

  1. Plot your coastlines using -JE. It is equidistant azimuthal which is the same properties as -JP.
  2. Now, overlay your data using -JP

The trick, of course, is to ensure the scale or widths are set up so that the two overlay well. Give it a try and report back how it goes. If your radii data can be spherical degrees then it may be simpler.

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3

Thank you, I don’t think I tried that one yet, but will do. Other projections worked that way near the center and near the edges, but were slightly “distorted” in between.

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