FFTN  FFTN N-Dimensional Forward FFT 


Usage
 
 Computes the DFT of an N-dimensional numerical array along all
 dimensions.  The general syntax for its use is
 
   y = fftn(x)
 
 which computes the same-size FFTs for each dimension of x.
 Alternately, you can specify the size vector
 
   y = fftn(x,dims)
 
 where dims is a vector of sizes.  The array x is zero padded
 or truncated as necessary in each dimension so that the output
 is of size dims. The fftn function is implemented by a sequence
 of calls to fft.
 