Trying to generate an SVG for an azimuthal antenna plot from a single column of values in decibels, range -40 up to a fixed maximum of 10. I've got it working, sort of. But the concentric rings for -40, -30 ... +10 are all of evenly spaced diameters. So it doesn't look right compared to the usual way. Normally the outer donut for 0 to +10 is bigger than the next one down for -10 to 0. And so on, each ring getting thinner and thinner as it proceeds down to the innermost circle with a center point of -40 dB.

So this is likely more a math question, except that I'm trying to work it in Perl. Obviously, Perl/Tk does it somehow, since a log scale exists. Has anyone a link to such an example?

Here is a link to what I'm working on. Folder on KY8D.net

foo.n2p.txt is the data. Drop the .txt after download.
foo.svg is the SVG graphic created by Perl.
Nec2Go_Plot.png is the plot I'm trying to prettify.
N2P_to_SVG.txt is the Perl script.

What it's about: There's an older antenna analysis program called Nec2Go. I'm wanting to make its plots suitable for inclusion in magazine articles, etc. So its 1-pixel lines on plots with grey backgrounds just won't do. Otherwise, though, it's better than certain newer ones.

In reply to Logarithmic Scale by aplonis

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