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<div class="moz-cite-prefix">Hello,<br>
<br>
Le 08/05/2014 20:34, <a class="moz-txt-link-abbreviated" href="mailto:andre.regis13@gmail.com">andre.regis13@gmail.com</a> a écrit :<br>
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<div>Dear colleagues,</div>
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<div>I have two functions f1(x) and f2(x). Using the following
formula: </div>
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<div>to calculate the results, get: 5.125[units]. </div>
<div>I tried to calculate separately by F1=fft(f1) ,
F2=fft(f2) and then multiply stems one by one and adding the
results. I found two problems:</div>
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This is a question about numerical computing rather than Scilab
itself.<br>
Anyway, why do you use some FFT instead of some straightforward
integration function (such as intg()) ?<br>
FFT would be useful whether the expected result would be e.g. the
cross-correlation function of your f1() and f2() ;<br>
but it is not the case : no lag appears in the integrand between
arguments of f1 and f2...<br>
<br>
HTH<br>
Samuel<br>
<br>
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