| 1 |
C $Header: /u/gcmpack/MITgcm/model/src/adams_bashforth2.F,v 1.9 2013/02/19 13:42:19 jmc Exp $ |
| 2 |
C $Name: $ |
| 3 |
|
| 4 |
#include "CPP_OPTIONS.h" |
| 5 |
|
| 6 |
CBOP |
| 7 |
C !ROUTINE: ADAMS_BASHFORTH2 |
| 8 |
C !INTERFACE: |
| 9 |
SUBROUTINE ADAMS_BASHFORTH2( |
| 10 |
I bi, bj, kArg, kSize, |
| 11 |
U gTracer, gTrNm1, |
| 12 |
O AB_gTr, |
| 13 |
I startAB, myIter, myThid ) |
| 14 |
C !DESCRIPTION: \bv |
| 15 |
C *==========================================================* |
| 16 |
C | S/R ADAMS_BASHFORTH2 |
| 17 |
C | o Extrapolate forward in time using quasi-second order |
| 18 |
C | Adams-Bashforth method. |
| 19 |
C *==========================================================* |
| 20 |
C | Either apply to tendency (kArg>0) at level k=kArg, |
| 21 |
C | or apply to state variable (kArg=0) for all levels |
| 22 |
C *==========================================================* |
| 23 |
C \ev |
| 24 |
|
| 25 |
C !USES: |
| 26 |
IMPLICIT NONE |
| 27 |
C == Global variables === |
| 28 |
#include "SIZE.h" |
| 29 |
#include "EEPARAMS.h" |
| 30 |
#include "PARAMS.h" |
| 31 |
|
| 32 |
C !INPUT/OUTPUT PARAMETERS: |
| 33 |
C == Routine Arguments == |
| 34 |
C bi,bj :: Tile indices |
| 35 |
C kArg :: if >0: apply AB on tendency at level k=kArg |
| 36 |
C :: if =0: apply AB on state variable and process all levels |
| 37 |
C kSize :: 3rd dimension of tracer and tendency arrays |
| 38 |
C gTracer :: in: Tendency/State at current time |
| 39 |
C :: out (kArg >0): Extrapolated Tendency at current time |
| 40 |
C gTrNm1 :: in: Tendency/State at previous time |
| 41 |
C :: out: (kArg >0) Save tendency at current time |
| 42 |
C :: out: (kArg =0) Extrapolated State at current time |
| 43 |
C AB_gTr :: Adams-Bashforth tendency increment |
| 44 |
C startAB :: number of previous time level available to start/restart AB |
| 45 |
C myIter :: Current time step number |
| 46 |
C myThid :: my Thread Id. number |
| 47 |
INTEGER bi, bj, kArg, kSize |
| 48 |
_RL gTracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,kSize) |
| 49 |
_RL gTrNm1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy,kSize) |
| 50 |
_RL AB_gTr (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
| 51 |
INTEGER startAB |
| 52 |
INTEGER myIter, myThid |
| 53 |
|
| 54 |
C !LOCAL VARIABLES: |
| 55 |
C == Local variables == |
| 56 |
C k :: level index |
| 57 |
C i,j :: Loop counters |
| 58 |
C abFac :: Adams bashforth extrapolation factor |
| 59 |
INTEGER i, j, k |
| 60 |
_RL abFac |
| 61 |
CEOP |
| 62 |
|
| 63 |
C Adams-Bashforth extrapolation factor |
| 64 |
IF ( myIter.EQ.nIter0 .AND. startAB.EQ.0 ) THEN |
| 65 |
abFac = 0. _d 0 |
| 66 |
ELSE |
| 67 |
abFac = 0.5 _d 0 + abEps |
| 68 |
ENDIF |
| 69 |
|
| 70 |
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
| 71 |
|
| 72 |
IF ( kArg.EQ.0 ) THEN |
| 73 |
C- Extrapolate forward in time the state variable, with AB weights: |
| 74 |
DO k=1,kSize |
| 75 |
DO j=1-OLy,sNy+OLy |
| 76 |
DO i=1-OLx,sNx+OLx |
| 77 |
AB_gTr(i,j) = abFac*( gTracer(i,j,k) - gTrNm1(i,j,k) ) |
| 78 |
gTrNm1(i,j,k) = gTracer(i,j,k) + AB_gTr(i,j) |
| 79 |
ENDDO |
| 80 |
ENDDO |
| 81 |
ENDDO |
| 82 |
ELSE |
| 83 |
C- Extrapolate forward in time the tendency, with AB weights: |
| 84 |
k = kArg |
| 85 |
DO j=1-OLy,sNy+OLy |
| 86 |
DO i=1-OLx,sNx+OLx |
| 87 |
AB_gTr(i,j) = abFac*( gTracer(i,j,k) - gTrNm1(i,j,k) ) |
| 88 |
gTrNm1(i,j,k) = gTracer(i,j,k) |
| 89 |
gTracer(i,j,k) = gTracer(i,j,k) + AB_gTr(i,j) |
| 90 |
ENDDO |
| 91 |
ENDDO |
| 92 |
ENDIF |
| 93 |
|
| 94 |
RETURN |
| 95 |
END |
Parent Directory
| 
Revision Log
| 
Revision Graph