SUAMP - output amp, phase, real or imag trace from (frequency, x) domain data

suamp <stdin >stdout mode=amp

Required parameters:
none

Optional parameter:
mode=amp output flag
amp = output amplitude traces
phase = output phase traces
real = output real parts
imag = output imag parts

Note:
The trace returned is half length from 0 to Nyquist.

Example:
sufft <data | suamp >amp_traces


Credits:
CWP: Shuki, Jack

Notes:
If efficiency becomes important consider inverting main loop
and repeating extraction code within the branches of the switch.

Trace header fields accessed: ns, trid
Trace header fields modified: ns, trid