| 1 | !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC |
|---|
| 2 | ! |
|---|
| 3 | ! FFTPACK 5.0 |
|---|
| 4 | ! Copyright (C) 1995-2004, Scientific Computing Division, |
|---|
| 5 | ! University Corporation for Atmospheric Research |
|---|
| 6 | ! Licensed under the GNU General Public License (GPL) |
|---|
| 7 | ! |
|---|
| 8 | ! Authors: Paul N. Swarztrauber and Richard A. Valent |
|---|
| 9 | ! |
|---|
| 10 | ! $Id: cfft2f.f,v 1.2 2004/06/15 21:08:32 rodney Exp $ |
|---|
| 11 | ! |
|---|
| 12 | !CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC |
|---|
| 13 | |
|---|
| 14 | SUBROUTINE CFFT2F (LDIM, L, M, C, WSAVE, LENSAV, & |
|---|
| 15 | & WORK, LENWRK, IER) |
|---|
| 16 | INTEGER L, M, LDIM, LENSAV, LENWRK, IER |
|---|
| 17 | COMPLEX C(LDIM,M) |
|---|
| 18 | REAL WSAVE(LENSAV), WORK(LENWRK) |
|---|
| 19 | ! |
|---|
| 20 | ! Initialize error return |
|---|
| 21 | ! |
|---|
| 22 | IER = 0 |
|---|
| 23 | ! |
|---|
| 24 | IF (L .GT. LDIM) THEN |
|---|
| 25 | IER = 5 |
|---|
| 26 | CALL XERFFT ('CFFT2F', -2) |
|---|
| 27 | GO TO 100 |
|---|
| 28 | ELSEIF (LENSAV .LT. 2*L + INT(LOG(REAL(L))) + & |
|---|
| 29 | & 2*M + INT(LOG(REAL(M))) +8) THEN |
|---|
| 30 | IER = 2 |
|---|
| 31 | CALL XERFFT ('CFFT2F', 6) |
|---|
| 32 | GO TO 100 |
|---|
| 33 | ELSEIF (LENWRK .LT. 2*L*M) THEN |
|---|
| 34 | IER = 3 |
|---|
| 35 | CALL XERFFT ('CFFT2F', 8) |
|---|
| 36 | GO TO 100 |
|---|
| 37 | ENDIF |
|---|
| 38 | ! |
|---|
| 39 | ! Transform X lines of C array |
|---|
| 40 | IW = 2*L+INT(LOG(REAL(L))*LOG(2.)) + 3 |
|---|
| 41 | CALL CFFTMF(L, 1, M, LDIM, C, (L-1) + LDIM*(M-1) +1, & |
|---|
| 42 | & WSAVE(IW), 2*M + INT(LOG(REAL(M))) + 4, & |
|---|
| 43 | & WORK, 2*L*M, IER1) |
|---|
| 44 | IF (IER1 .NE. 0) THEN |
|---|
| 45 | IER = 20 |
|---|
| 46 | CALL XERFFT ('CFFT2F',-5) |
|---|
| 47 | GO TO 100 |
|---|
| 48 | ENDIF |
|---|
| 49 | ! |
|---|
| 50 | ! Transform Y lines of C array |
|---|
| 51 | IW = 1 |
|---|
| 52 | CALL CFFTMF (M, LDIM, L, 1, C, (M-1)*LDIM + L, & |
|---|
| 53 | & WSAVE(IW), 2*L + INT(LOG(REAL(L))) + 4, & |
|---|
| 54 | & WORK, 2*M*L, IER1) |
|---|
| 55 | IF (IER1 .NE. 0) THEN |
|---|
| 56 | IER = 20 |
|---|
| 57 | CALL XERFFT ('CFFT2F',-5) |
|---|
| 58 | ENDIF |
|---|
| 59 | ! |
|---|
| 60 | 100 CONTINUE |
|---|
| 61 | RETURN |
|---|
| 62 | END |
|---|