/[MITgcm]/MITgcm/pkg/zonal_filt/zonal_filt_nofill.F
ViewVC logotype

Contents of /MITgcm/pkg/zonal_filt/zonal_filt_nofill.F

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.2 - (show annotations) (download)
Fri Feb 2 21:36:30 2001 UTC (23 years, 4 months ago) by adcroft
Branch: MAIN
Changes since 1.1: +91 -0 lines
Merged changes from branch "branch-atmos-merge" into MAIN (checkpoint34)
 - substantial modifications to algorithm sequence (dynamics.F)
 - packaged OBCS, Shapiro filter, Zonal filter, Atmospheric Physics

1 C $Header: /u/gcmpack/models/MITgcmUV/pkg/zonal_filt/Attic/zonal_filt_nofill.F,v 1.1.2.1 2001/01/24 16:56:07 adcroft Exp $
2
3 #include "ZONAL_FILT_OPTIONS.h"
4
5 SUBROUTINE ZONAL_FILT_NOFILL(
6 U field,
7 I jMin, jMax, kMin, kMax, bi, bj, gridLoc, myThid )
8 C /==========================================================\
9 C | S/R ZONAL_FILT_NOFILL |
10 C | o Apply FFT filter to a latitude circle. |
11 C | *No fill* |
12 C \==========================================================/
13 IMPLICIT NONE
14
15 C == Global data ==
16 #include "SIZE.h"
17 #include "ZONAL_FILT.h"
18 #include "FFTPACK.h"
19
20 C == Routine arguments ==
21 C jMin - Range of points to filter
22 C jMax
23 C kMin
24 C kMax
25 C bi
26 C bj
27 C myThid - Thread number of this instance of FILTER_LATCIRC_FFT_APPLY
28 C field - Field to filter
29 C gridLoc - Orientation (U or V) of field.
30 INTEGER myThid
31 INTEGER gridLoc
32 C Real*8 field(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
33 Real*8 field(1-OLx:sNx+OLx,1-OLy:sNy+OLy,1,nSx,nSy)
34 INTEGER jMin, jMax, kMin, kMax, bi, bj
35
36 #ifdef ALLOW_ZONAL_FILT
37
38 C == Local data ==
39 Real*8 phi(Nx)
40 INTEGER I, J, K
41
42 DO k=kMin, kMax
43 DO j=jMin, jMax
44
45 C o Copy zonal line of field into local workspace
46 DO i=1,sNx
47 phi(I) = field(i,j,k,bi,bj)
48 ENDDO
49
50 C o Forward transform (using specific FFT package)
51 C CALL R8FFTF( Nx, phi, FFTPACKWS(1,bj) )
52 CALL R8FFTF1( Nx, phi,
53 & FFTPACKWS1(1,bj), FFTPACKWS2(1,bj),FFTPACKWS3(1,bj) )
54
55 C o Apply amplitude filter and normalize
56 IF (gridLoc .EQ. 1) THEN
57 DO i=1, Nx
58 phi(i)=phi(i)*ampFactor(i,j,bi,bj)/float(Nx)
59 ENDDO
60 ELSEIF (gridLoc .EQ. 2) THEN
61 DO i=1, Nx
62 phi(i)=phi(i)*ampFactorV(i,j,bi,bj)/float(Nx)
63 ENDDO
64 ELSE
65 WRITE(0,*) 'Error: gridLoc = ',gridLoc
66 STOP 'Error: gridLoc has illegal value'
67 ENDIF
68
69 C o Backward transform (using specific FFT package)
70 C CALL R8FFTB( Nx, phi, FFTPACKWS(1,bj) )
71 CALL R8FFTB1( Nx, phi,
72 & FFTPACKWS1(1,bj), FFTPACKWS2(1,bj),FFTPACKWS3(1,bj) )
73
74 C o Do periodic wrap around by hand
75 DO i=1-OLx,0
76 field(i,j,k,bi,bj) = phi(sNx+i)
77 ENDDO
78 DO i=1,sNx
79 field(i,j,k,bi,bj) = phi(I)
80 ENDDO
81 DO i=sNx+1,sNx+OLx
82 field(i,j,k,bi,bj) = phi(i-sNx)
83 ENDDO
84
85 ENDDO
86 ENDDO
87
88 #endif /* ALLOW_ZONAL_FILT */
89
90 RETURN
91 END

  ViewVC Help
Powered by ViewVC 1.1.22