comp.lang.idl-pvwave archive
Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
Home » Public Forums » archive » FFT wierdness in WAVE
Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend  		Switch to threaded view of this topic Create a new topic Submit Reply
FFT wierdness in WAVE [message #6088] Wed, 27 March 1996 00:00
howie is currently offline  howie
Messages: 5
Registered: May 1994
Junior Member
Can anyone here enlighten me on why the plots produced with the
following commands are so different?

Other vector lengths which produce this strange behavior are;

5788 5788+16 5788+48
9848 9848-16 9848-32
and others

> plot,abs(fft(findgen(8395),-1)) - works!
> plot,abs(fft(findgen(8396),-1)) - fails! Peaks where none should be.

The contents of the vector do not matter. When the vector length is
8396 you get a spike on top of the proper spectrum.

Any ideas?

Report message to a moderator

  Switch to threaded view of this topic Create a new topic Submit Reply
Previous Topic: Installation of idl under Win3.11
Next Topic: help to a freshman with show3

-=] Back to Top [=-
[ Syndicate this forum (XML) ] [ RSS ] [ PDF ]

Current Time: Sat Oct 11 13:06:00 PDT 2025

Total time taken to generate the page: 0.47961 seconds
.:: Contact :: Home ::.

Powered by: FUDforum 3.0.7.
Copyright ©2001-2013 FUDforum Bulletin Board Software