c06fqf
c06fqf
© Numerical Algorithms Group, 2002.
Purpose
C06FQF Multiple 1-D Hermitian discrete Fourier transforms
Synopsis
[x,trig,ifail] = c06fqf(x<,trig,init,ifail>)
Description
p
Given m Hermitian sequences of n complex data values z , for
j
j=0,1,...,n-1; p=1,2,...,m, this routine simultaneously
calculates the Fourier transforms of all the sequences defined
by:
n-1
^p 1 -- p ( 2(pi)jk)
x = --- > z *exp(-i -------), k=0,1,...,n-1; p=1,2,...,m.
k _ -- j ( n )
\/n j=0
1
(Note the scale factor --- in this definition.)
_
\/n
The transformed values are purely real (see also the Chapter
Introduction).
The discrete Fourier transform is sometimes defined using a
positive sign in the exponential term
n-1
^p 1 -- p ( 2(pi)jk)
x = --- > z *exp(+i -------).
k _ -- j ( n )
\/n j=0
To compute this form, this routine should be preceded by a call
^p
to C06GQF to form the complex conjugates of the z .
j
Parameters
c06fqf
Required Input Arguments:
x (:,:) real
Optional Input Arguments: <Default>
trig (:) real zeros(2*size(x,2),1)
init (1) string c06fqf04(trig)
ifail integer -1
Output Arguments:
x (:,:) real
trig (:) real
ifail integer