Paul said:
I would think that for the graph to make sense it would represent an
overlay of comparable information. (Both items have the same
independent variable)
That's not always the case. I have plotted waveforms (independent variable:
time) and the spectrum of that waveform (independent variable: frequency) on
the same graph. That is not at all uncommon in my line of work, and it is a
chart that packs a lot of information.
See my reply to Nashya's other post with the identical question. Excel can
do it, but it's hidden pretty well.
Dave
dvt at psu dot edu