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*ftpplot*
- Distribution of FFT coefficient values

**The distribution of coefficient values for a single FFT is exponential
if the original data contain no periodic signal.
This distribution can be plotted and inspected.
Significant coefficients
will appear beyond the high-value end of the normal distributions.
The width of the histogram bins can be adjusted (before running ***fft*) to get a nice looking
plot.

**To plot the power density distribution created by ***fft*.

xt> fft.histogram_bi=0.5 # if necessary, adjust number for an aesthetic plot
xt> ftpplot
input table file: rp90_ftp

**The plot will appear on the screen. To make hard copy, type
= with cursor within plot. To return to text window type q.
**

*rsdc@cfa.harvard.edu *

1998-06-10