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From: dpb <none@non.net>
Newsgroups: comp.soft-sys.matlab
Subject: Re: FFT -- sum( v(t))   /=  sum (v(t))
Date: Mon, 02 Nov 2009 17:56:20 -0600
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Travis Bland wrote:
> Hi,
...
> I notice when i read in the file to volt_t, the precision isn't very
> high. My values are #*e-06 , and matlab gives   0.0001 or 0.0000.
> Could this be my issue; if so, how do i fix it? If not, any
> suggestions on what to do?
> 
ML uses default double for internal representation irrespective of what 
the command window display format is.

Try

format long

or

format long e

to see full internal precision.

doc format   % for more info

As for the fft normalization, w/ correct normalization you should find 
all the energy, yes.

--