From: Phil <phi39466@yahoo.com>
To: gsl-discuss@sources.redhat.com
Subject: differentiating FFT'd data
Date: Thu, 19 Dec 2002 11:40:00 -0000 [thread overview]
Message-ID: <20021218234344.7018.qmail@web41405.mail.yahoo.com> (raw)
I have pressure data from ocean waves and have
used the FFT to low-pass filter the data similiar
to the example at the end of ch. 15 of the manual
and have had very good results. Now I would like
to find local max and min values. Isn't there a
way to represent this "wave" as a series of sin
and cosine functions, it has been years since I
studied this. I could then differentiate this
directly rather than numerically. I would
appreciate any help.
Phil
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reply other threads:[~2002-12-18 23:43 UTC|newest]
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