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Subject: Re: fft, frequecy of a signal
Date: Tue, 17 Jun 2008 13:14:02 +0000 (UTC)
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roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) wrote in 
message <g387sh$48v$1@canopus.cc.umanitoba.ca>...
> Standard definition of frequency: samples per second.
> So divide the number of samples (the length) by the 
total time.
> (Provided, that is, that the signal was sampled at 
regular
> intervals.)
> -- 
>   "Prevention is the daughter of intelligence."
>                                               -- Sir 
Walter Raleigh


I'm new to a lot of this, so this question is as much for 
my own understanding as it is for the original poster.

Wouldn't this depend on the 'type' of frequency they are 
looking for?  Taking the number of samples and dividing by 
the total time would give them the sampling frequency, but 
not the frequency of the analog signal that was sampled.  
For instance, you can have a 1 Hz signal that is sampled 
at 1 MHz.  (# of samples) / (total time) would equal 1 
MHz, but that isn't the frequency of the signal, which is 
1 Hz.

Does that make any sense or am I totally off-base here?