c06ecf

Purpose

Synopsis

[x,y,ifail] = c06ecf(x,y<,ifail>)

Description

 
 Given a sequence of n complex data values z , for j=0,1,...,n-1, 
                                            j                    
 this routine calculates their discrete Fourier transform defined 
 by:
 
                   n-1                  
           ^    1  --       (   2(pi)jk)
           z = --- >  z *exp(-i -------), k=0,1,...,n-1.
            k    _ --  j    (      n   )
               \/n j=0                  
 
                             1                     
 (Note the scale factor of  --- in this definition.)
                              _                    
                            \/n                    
 
 To compute the inverse discrete Fourier transform defined by:
 
                          n-1                  
                  ^    1  --       (   2(pi)jk)
                  w = --- >  z *exp(+i -------),
                   k    _ --  j    (      n   )
                      \/n j=0                  
 
 this routine should be preceded and followed by negating the
 imaginary parts of the data to form the complex 
 conjugates of the z  and the z .
                    j          k
 
 There are some restrictions on the value of n.
 

Parameters

c06ecf

Required Input Arguments:

x (:)                                 real
y (:)                                 real

Optional Input Arguments:                       <Default>

ifail                                 integer  -1

Output Arguments:

x (:)                                 real
y (:)                                 real
ifail                                 integer