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gforget |
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C $Header: /u/gcmpack/MITgcm/model/src/rotate_uv2en.F,v 1.1 2010/03/04 03:42:30 gforget Exp $ |
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C $Name: $ |
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#include "CPP_OPTIONS.h" |
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C-- File rotate_uv2en.F: Routines to handle a vector coordinate system rotation. |
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C-- Contents |
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C-- o ROTATE_UV2EN_RL |
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C-- o ROTATE_UV2EN_RS |
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subroutine rotate_uv2en_rl( |
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U uFldX, vFldY, |
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U uFldE, vFldN, |
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I xy2en, switchGrid, applyMask, kSize, mythid |
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& ) |
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c ================================================================== |
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c SUBROUTINE rotate_uv2en_rl |
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c ================================================================== |
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c |
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c o uFldX/vFldY are in the model grid directions. |
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c o uFldE/vFldN are eastward/northward. |
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c o This routine goes from uFldX/vFldY to uFldE/vFldN (for xy2en=.TRUE.) |
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c or vice versa (for xy2en=.FALSE.). |
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c o uFldX/vFldY may be at the C grid velocity points, or at the A grid |
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c velocity points (i.e. the C grid cell center). uFldE/vFldN are always |
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c at the cell center. If switchGrid=.TRUE. we go from C grid uFldX/vFldY |
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c to A grid uFldE/vFldN, or vice versa. If switchGrid=.FALSE. we go |
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c from A grid uFldX/vFldY to A grid uFldE/vFldN, or vice versa. |
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c o If applyMask=.TRUE. then masks are applied to the output. |
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c If kSize=1 (resp. nr) we then use the surface (resp. 3D) masks. |
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c o In any case it is assumed that exchanges are done on the outside. |
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c |
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c ================================================================== |
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c SUBROUTINE rotate_uv2en_rl |
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c ================================================================== |
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implicit none |
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c == global variables == |
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#include "EEPARAMS.h" |
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#include "SIZE.h" |
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#include "PARAMS.h" |
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#include "GRID.h" |
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c == routine arguments == |
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integer kSize |
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logical xy2en, switchGrid, applyMask |
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_RL uFldX(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RL vFldY(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RL uFldE(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RL vFldN(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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integer mythid |
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c == local variables == |
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integer bi,bj |
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integer i,j,k,kk |
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_RL tmpU(1-olx:snx+olx,1-oly:sny+oly) |
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_RL tmpV(1-olx:snx+olx,1-oly:sny+oly) |
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CHARACTER*(MAX_LEN_MBUF) msgBuf |
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c == end of interface == |
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if ( (kSize.NE.1).AND.(kSize.NE.nr) |
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& .AND.(applyMask) ) then |
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WRITE(msgBuf,'(2A,I4,A)') ' ROTATE_UV2EN: ', |
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& 'no mask has ',kSize,' levels' |
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CALL PRINT_ERROR(msgBuf, myThid) |
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STOP 'ABNROMAL END: S/R ROTATE_UV2EN' |
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endif |
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do bj = mybylo(mythid),mybyhi(mythid) |
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do bi = mybxlo(mythid),mybxhi(mythid) |
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do k = 1,kSize |
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if ( (kSize.EQ.1).AND.(usingPCoords) ) then |
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kk=nr |
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else |
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kk=k |
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endif |
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if ( xy2en ) then |
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c go from uFldX/vFldY to uFldE/vFldN |
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if ( switchGrid ) then |
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C 1a) go from C grid velocity points to A grid velocity points |
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do i = 1-olx,snx+olx |
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tmpU(i,sny+Oly)=0. |
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tmpV(i,sny+Oly)=0. |
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enddo |
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do j = 1-oly,sny+oly-1 |
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tmpU(snx+Olx,j)=0. |
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tmpV(snx+Olx,j)=0. |
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do i = 1-olx,snx+olx-1 |
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tmpU(i,j) = 0.5 _d 0 |
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& *( uFldX(i+1,j,k,bi,bj) + uFldX(i,j,k,bi,bj) ) |
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tmpV(i,j) = 0.5 _d 0 |
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& *( vFldY(i,j+1,k,bi,bj) + vFldY(i,j,k,bi,bj) ) |
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if (applyMask) then |
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tmpU(i,j) = tmpU(i,j) * maskC(i,j,kk,bi,bj) |
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tmpV(i,j) = tmpV(i,j) * maskC(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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else |
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C 1b) stay at A grid velocity points (i.e. at the C grid cell center) |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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tmpU(i,j) = uFldX(i,j,k,bi,bj) |
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tmpV(i,j) = vFldY(i,j,k,bi,bj) |
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if (applyMask) then |
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tmpU(i,j) = tmpU(i,j) * maskC(i,j,kk,bi,bj) |
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tmpV(i,j) = tmpV(i,j) * maskC(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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endif!if ( switchGrid ) then |
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C 2) rotation |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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uFldE(i,j,k,bi,bj) = |
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& angleCosC(i,j,bi,bj)*tmpU(i,j) |
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& -angleSinC(i,j,bi,bj)*tmpV(i,j) |
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vFldN(i,j,k,bi,bj) = |
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& angleSinC(i,j,bi,bj)*tmpU(i,j) |
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& +angleCosC(i,j,bi,bj)*tmpV(i,j) |
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enddo |
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enddo |
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else!if (xy2en) then |
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c go from uFldE/vFldN to uFldX/vFldY |
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C 1) rotation |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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tmpU(i,j) = |
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& angleCosC(i,j,bi,bj)*uFldE(i,j,k,bi,bj) |
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& +angleSinC(i,j,bi,bj)*vFldN(i,j,k,bi,bj) |
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tmpV(i,j) = |
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& -angleSinC(i,j,bi,bj)*uFldE(i,j,k,bi,bj) |
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& +angleCosC(i,j,bi,bj)*vFldN(i,j,k,bi,bj) |
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enddo |
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enddo |
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if ( switchGrid ) then |
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C 2a) go from A grid velocity points to C grid velocity points |
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do i = 1-olx,snx+olx |
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uFldX(i,1,k,bi,bj)=0. |
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vFldY(i,1,k,bi,bj)=0. |
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enddo |
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do j = 1-oly+1,sny+oly |
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uFldX(1,j,k,bi,bj)=0. |
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vFldY(1,j,k,bi,bj)=0. |
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do i = 1-olx+1,snx+olx |
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uFldX(i,j,k,bi,bj) = 0.5 _d 0 |
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& *( tmpU(i-1,j) + tmpU(i,j) ) |
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vFldY(i,j,k,bi,bj) = 0.5 _d 0 |
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& *( tmpV(i,j-1) + tmpV(i,j) ) |
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if (applyMask) then |
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uFldX(i,j,k,bi,bj)=uFldX(i,j,k,bi,bj)*maskW(i,j,kk,bi,bj) |
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vFldY(i,j,k,bi,bj)=vFldY(i,j,k,bi,bj)*maskS(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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else |
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C 2b) stay at A grid velocity points (i.e. at the C grid cell center) |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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uFldX(i,j,k,bi,bj) = tmpU(i,j) |
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vFldY(i,j,k,bi,bj) = tmpV(i,j) |
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if (applyMask) then |
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uFldX(i,j,k,bi,bj)=uFldX(i,j,k,bi,bj)*maskC(i,j,kk,bi,bj) |
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vFldY(i,j,k,bi,bj)=vFldY(i,j,k,bi,bj)*maskC(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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endif!if ( switchGrid ) then |
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endif!if (xy2en) then |
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enddo |
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enddo |
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enddo |
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return |
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end |
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subroutine rotate_uv2en_rs( |
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U uFldX, vFldY, |
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U uFldE, vFldN, |
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I xy2en, switchGrid, applyMask, kSize, mythid |
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& ) |
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c ================================================================== |
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c SUBROUTINE rotate_uv2en_rs |
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c ================================================================== |
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c |
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c o uFldX/vFldY are in the model grid directions. |
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c o uFldE/vFldN are eastward/northward. |
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c o This routine goes from uFldX/vFldY to uFldE/vFldN (for xy2en=.TRUE.) |
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c or vice versa (for xy2en=.FALSE.). |
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c o uFldX/vFldY may be at the C grid velocity points, or at the A grid |
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c velocity points (i.e. the C grid cell center). uFldE/vFldN are always |
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c at the cell center. If switchGrid=.TRUE. we go from C grid uFldX/vFldY |
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c to A grid uFldE/vFldN, or vice versa. If switchGrid=.FALSE. we go |
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c from A grid uFldX/vFldY to A grid uFldE/vFldN, or vice versa. |
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c o If applyMask=.TRUE. then masks are applied to the output. |
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c If kSize=1 (resp. nr) we then use the surface (resp. 3D) masks. |
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c o In any case it is assumed that exchanges are done on the outside. |
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c |
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c ================================================================== |
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c SUBROUTINE rotate_uv2en_rs |
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c ================================================================== |
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implicit none |
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c == global variables == |
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#include "EEPARAMS.h" |
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#include "SIZE.h" |
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#include "PARAMS.h" |
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#include "GRID.h" |
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c == routine arguments == |
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integer kSize |
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logical xy2en, switchGrid, applyMask |
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_RS uFldX(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RS vFldY(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RS uFldE(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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_RS vFldN(1-olx:snx+olx,1-oly:sny+oly,kSize,nsx,nsy) |
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integer mythid |
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c == local variables == |
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integer bi,bj |
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integer i,j,k,kk |
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_RS tmpU(1-olx:snx+olx,1-oly:sny+oly) |
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_RS tmpV(1-olx:snx+olx,1-oly:sny+oly) |
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CHARACTER*(MAX_LEN_MBUF) msgBuf |
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c == end of interface == |
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if ( (kSize.NE.1).AND.(kSize.NE.nr) |
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& .AND.(applyMask) ) then |
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WRITE(msgBuf,'(2A,I4,A)') ' ROTATE_UV2EN: ', |
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& 'no mask has ',kSize,' levels' |
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CALL PRINT_ERROR(msgBuf, myThid) |
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STOP 'ABNROMAL END: S/R ROTATE_UV2EN' |
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endif |
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do bj = mybylo(mythid),mybyhi(mythid) |
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do bi = mybxlo(mythid),mybxhi(mythid) |
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do k = 1,kSize |
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if ( (kSize.EQ.1).AND.(usingPCoords) ) then |
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kk=nr |
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else |
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kk=k |
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endif |
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if ( xy2en ) then |
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c go from uFldX/vFldY to uFldE/vFldN |
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if ( switchGrid ) then |
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C 1a) go from C grid velocity points to A grid velocity points |
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do i = 1-olx,snx+olx |
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tmpU(i,sny+Oly)=0. |
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tmpV(i,sny+Oly)=0. |
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enddo |
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do j = 1-oly,sny+oly-1 |
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tmpU(snx+Olx,j)=0. |
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tmpV(snx+Olx,j)=0. |
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do i = 1-olx,snx+olx-1 |
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tmpU(i,j) = 0.5 _d 0 |
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& *( uFldX(i+1,j,k,bi,bj) + uFldX(i,j,k,bi,bj) ) |
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tmpV(i,j) = 0.5 _d 0 |
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& *( vFldY(i,j+1,k,bi,bj) + vFldY(i,j,k,bi,bj) ) |
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if (applyMask) then |
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tmpU(i,j) = tmpU(i,j) * maskC(i,j,kk,bi,bj) |
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tmpV(i,j) = tmpV(i,j) * maskC(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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else |
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C 1b) stay at A grid velocity points (i.e. at the C grid cell center) |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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tmpU(i,j) = uFldX(i,j,k,bi,bj) |
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tmpV(i,j) = vFldY(i,j,k,bi,bj) |
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if (applyMask) then |
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tmpU(i,j) = tmpU(i,j) * maskC(i,j,kk,bi,bj) |
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tmpV(i,j) = tmpV(i,j) * maskC(i,j,kk,bi,bj) |
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endif |
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enddo |
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enddo |
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endif!if ( switchGrid ) then |
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C 2) rotation |
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do j = 1-oly,sny+oly |
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do i = 1-olx,snx+olx |
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uFldE(i,j,k,bi,bj) = |
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& angleCosC(i,j,bi,bj)*tmpU(i,j) |
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& -angleSinC(i,j,bi,bj)*tmpV(i,j) |
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vFldN(i,j,k,bi,bj) = |
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& angleSinC(i,j,bi,bj)*tmpU(i,j) |
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& +angleCosC(i,j,bi,bj)*tmpV(i,j) |
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enddo |
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enddo |
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else!if (xy2en) then |
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c go from uFldE/vFldN to uFldX/vFldY |
| 317 |
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| 318 |
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C 1) rotation |
| 319 |
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do j = 1-oly,sny+oly |
| 320 |
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do i = 1-olx,snx+olx |
| 321 |
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tmpU(i,j) = |
| 322 |
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& angleCosC(i,j,bi,bj)*uFldE(i,j,k,bi,bj) |
| 323 |
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& +angleSinC(i,j,bi,bj)*vFldN(i,j,k,bi,bj) |
| 324 |
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tmpV(i,j) = |
| 325 |
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& -angleSinC(i,j,bi,bj)*uFldE(i,j,k,bi,bj) |
| 326 |
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& +angleCosC(i,j,bi,bj)*vFldN(i,j,k,bi,bj) |
| 327 |
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enddo |
| 328 |
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enddo |
| 329 |
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| 330 |
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if ( switchGrid ) then |
| 331 |
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C 2a) go from A grid velocity points to C grid velocity points |
| 332 |
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do i = 1-olx,snx+olx |
| 333 |
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uFldX(i,1,k,bi,bj)=0. |
| 334 |
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vFldY(i,1,k,bi,bj)=0. |
| 335 |
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enddo |
| 336 |
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do j = 1-oly+1,sny+oly |
| 337 |
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uFldX(1,j,k,bi,bj)=0. |
| 338 |
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vFldY(1,j,k,bi,bj)=0. |
| 339 |
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do i = 1-olx+1,snx+olx |
| 340 |
|
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uFldX(i,j,k,bi,bj) = 0.5 _d 0 |
| 341 |
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& *( tmpU(i-1,j) + tmpU(i,j) ) |
| 342 |
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vFldY(i,j,k,bi,bj) = 0.5 _d 0 |
| 343 |
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& *( tmpV(i,j-1) + tmpV(i,j) ) |
| 344 |
|
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if (applyMask) then |
| 345 |
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uFldX(i,j,k,bi,bj)=uFldX(i,j,k,bi,bj)*maskW(i,j,kk,bi,bj) |
| 346 |
|
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vFldY(i,j,k,bi,bj)=vFldY(i,j,k,bi,bj)*maskS(i,j,kk,bi,bj) |
| 347 |
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endif |
| 348 |
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enddo |
| 349 |
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enddo |
| 350 |
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else |
| 351 |
|
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C 2b) stay at A grid velocity points (i.e. at the C grid cell center) |
| 352 |
|
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do j = 1-oly,sny+oly |
| 353 |
|
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do i = 1-olx,snx+olx |
| 354 |
|
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uFldX(i,j,k,bi,bj) = tmpU(i,j) |
| 355 |
|
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vFldY(i,j,k,bi,bj) = tmpV(i,j) |
| 356 |
|
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if (applyMask) then |
| 357 |
|
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uFldX(i,j,k,bi,bj)=uFldX(i,j,k,bi,bj)*maskC(i,j,kk,bi,bj) |
| 358 |
|
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vFldY(i,j,k,bi,bj)=vFldY(i,j,k,bi,bj)*maskC(i,j,kk,bi,bj) |
| 359 |
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endif |
| 360 |
|
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enddo |
| 361 |
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enddo |
| 362 |
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endif!if ( switchGrid ) then |
| 363 |
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| 364 |
|
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endif!if (xy2en) then |
| 365 |
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| 366 |
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enddo |
| 367 |
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enddo |
| 368 |
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enddo |
| 369 |
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| 370 |
|
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return |
| 371 |
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end |
| 372 |
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