Date: Aug 25, 2008 10:20 AM
Author: Forrest
Subject: How to extract data points from a plot (can't use 'ginput')

I'm using the 'psd' function to take the power spectral 
density of a waveform. Afterwards I can view the plot of
the psd, however, I can't seem to find the data that is
being plotted from the psd. I have the plot, but I can't
find the x and y coordinates. I can't use ginput because
there are 5000 data points.

I've done some searches both on this site and on the web
and can't find anything on this. One would think that
this would be a very commonly used feature. Yes, most of
the time users plot data that they already have stored in
variables, however, when performing complex functions that
plot to a graph those variables aren't accessible (or are