[SciPy-User] Is Numpy rfft returning the correct number of points?

[Matthieu Brucher]

It's the amplitude at fs/2 (it's a real value).

2011/2/16 Brendan Arnold <brendanarnold at gmail.com>

> Right, but what I was wondering about is that instead of 2048 points
> returned 2049 are returned, what is the last point?
>
> Brendan
>
>
>
> On 16 February 2011 20:33, Matthieu Brucher <matthieu.brucher at gmail.com>
> wrote:
> > Hi,
> >
> > Yes, it is correct. When doing a real FFT, you have 4096 points, but the
> > values 1:2048 are conjugated with 2049:4096, so you need only values
> 0:2049
> > to get your original signal back.
> >
> > Matthieu
> >
> > Matthieu
> >
> > 2011/2/16 Brendan Arnold <brendanarnold at gmail.com>
> >>
> >> Hi there,
> >>
> >> When I run numpy.fft.rfft on an array of length 4096, it returns an
> >> array of 2049 and not 2048. Is this right behaviour?
> >>
> >> I am using numpy 1.5.1
> >>
> >> Brendan
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> >
> >
> > --
> > Information System Engineer, Ph.D.
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-- 
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