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Date: 17 Feb 2004 08:30:24 +0200
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From: Eli Zaretskii <eliz AT elta DOT co DOT il>
To: Ethan Rosenberg <ethros AT earthlink DOT net>
CC: djgpp AT delorie DOT com, sandmann AT clio DOT rice DOT edu
In-reply-to: <3.0.1.16.20040216231142.38e7a7cc@earthlink.net> (message from
	Ethan Rosenberg on Mon, 16 Feb 2004 23:11:42 -0500)
Subject: Re: Cross Platform Incompatabilites? - code fragments
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> Date: Mon, 16 Feb 2004 23:11:42 -0500
> From: Ethan Rosenberg <ethros AT earthlink DOT net>
> 
> The following are code FRAGMENTS from the program.  My feelings are that
> the error is in the integration routine.  etot is defined as FLOAT.
> 
> I have extracted these fragments for a program of approx. 3000 lines of
> code.  I hope I am not burdening you with too much.

Did you ever try to do the computations in `double' instead of
`float', and if so, what were the results?

One problem that bothers me is the possibility of overflow or
catastrophic loss of precision due to limited range of `float's.
What is the maximum absolute value and the minimum absolute value of
the numbers in the fft_out[] array after the first loop in the
fragments you posted:

    for (l = 0; l < FFT_LEN; l++)
                fft_out[l] = amp(l, wave, 14);