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SCFFT
Routine Documentation— Input: INTEGER MODE
The value of MODE on input determines the operation performed by
SCFFT
.
On input:
- MODE=0 : only default initializations (specific to N) are performed; this is usually followed by calls to the same routine with MODE=-1 or 1.
- MODE=1 : a real transform is performed. Initializations are assumed to have been performed by a prior call to
SCFFT
.- MODE=2 : (default) initializations and a real transform are performed.
- MODE=100 : similar to MODE=0; only initializations are performed, but first a plan is generated. This plan is chosen based on the fastest FFT computation for a subset of all possible plans.
— Input/Output: REAL X(N)
On input: X contains the real sequence of length N to be transformed.
On output: X contains the transformed Hermitian sequence.
CALL SCFFT(0,N,X,COMM,INFO) CALL SCFFT(1,N,X,COMM,INFO) DO 10 I = N/2+2, N X(I) = -X(I) 10 CONTINUE CALL CSFFT(2,N,X,COMM,INFO) |