c06fuf

Purpose

Synopsis

[x,y,trigm,trign,ifail] = c06fuf(x,y<,trigm,trign,init,ifail>)

Description

 
 This routine computes the two-dimensional discrete Fourier 
 transform of a bivariate sequence of complex data values z    , 
                                                           j j  
                                                            1 2 
 where j =0,1,...,m-1, j =0,1,...,n-1.
        1               2            
 
 The discrete Fourier transform is here defined by:
 
                   m-1  n-1          (       ( j k    j k ))
       ^       1   --   --           (       (  1 1    2 2))
       z    = ---- >    >   z    *exp(-2(pi)i( ---- + ----)),
                __ --   --   j j     (       (  m      n  ))
        k k   \/mn j =0 j =0  1 2                           
         1 2        1    2                              
 
 where k =0,1,...,m-1, k =0,1,...,n-1.
        1               2            
 
                             1                      
 (Note the scale factor of  ---- in this definition.)
                              __                    
                            \/mn                    
 
 To compute the inverse discrete Fourier transform, defined with 
 exp(+2(pi)i(...)) in the above formula instead of 
 exp(-2(pi)i(...)), this routine should be preceded and followed 
 by negating the imaginary parts of the data to form the
 complex conjugates of the data values and the transform.
 

Parameters

c06fuf

Required Input Arguments:

x (:,:)                               real
y (:,:)                               real

Optional Input Arguments:                       <Default>

trigm (:)                             real     zeros(2*size(x,1),1)
trign (:)                             real     zeros(2*size(x,2),1)
init (1)                              string   c06fuf05(trigm,trign)
ifail                                 integer  -1

Output Arguments:

x (:,:)                               real
y (:,:)                               real
trigm (:)                             real
trign (:)                             real
ifail                                 integer