2D FFT (fft)

Enclosed are source and makefile for creating a parallel 2dfft that runs on the
iPSC/860. Included is a driver routine that attempts to run the 27 test cases
on the input file, in.dat. Not all test cases will execute successfully, as
some are either too small or too large for your machine. The driver contains
code to by-pass such cases. This code assumes that there are 8Mbytes of mem-
ory per processor. If your machine has more memory, change the dimension of
the arrays and the number in line 53 of driver2d.f.

The routine that performs the parallel 2dfft (file fft2d) assumes that the
matrix is stored with the first dimension distributed (i.e., the matrix is
decomposed into horizontal strips that are stored on successive processors).
The user can specify how the matrix is stored upon returning from the 2dfft.
Set the parameter 
		distrib = 2
to return with the second dimension distributed. Any other value for this
parameter causes the routine to return with the original decomposition (first
dimension distributed). Returning with the second dimension distributed is
significantly faster.

The software that is enclosed works for COMPLEX*8 data.
