--- MITgcm/pkg/seaice/seaice_jfnk.F 2013/01/17 08:51:15 1.16 +++ MITgcm/pkg/seaice/seaice_jfnk.F 2016/01/28 12:54:12 1.30 @@ -1,7 +1,10 @@ -C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/seaice/seaice_jfnk.F,v 1.16 2013/01/17 08:51:15 mlosch Exp $ +C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/seaice/seaice_jfnk.F,v 1.30 2016/01/28 12:54:12 mlosch Exp $ C $Name: $ #include "SEAICE_OPTIONS.h" +#ifdef ALLOW_AUTODIFF +# include "AUTODIFF_OPTIONS.h" +#endif C-- File seaice_jfnk.F: seaice jfnk dynamical solver S/R: C-- Contents @@ -53,9 +56,7 @@ INTEGER myIter INTEGER myThid -#if ( (defined SEAICE_CGRID) && \ - (defined SEAICE_ALLOW_JFNK) && \ - (defined SEAICE_ALLOW_DYNAMICS) ) +#ifdef SEAICE_ALLOW_JFNK C !FUNCTIONS: LOGICAL DIFFERENT_MULTIPLE EXTERNAL DIFFERENT_MULTIPLE @@ -68,6 +69,12 @@ INTEGER newtonIter INTEGER krylovIter, krylovFails INTEGER totalKrylovItersLoc, totalNewtonItersLoc +C FGMRES parameters +C im :: size of Krylov space +C ifgmres :: interation counter + INTEGER im + PARAMETER ( im = 50 ) + INTEGER ifgmres C FGMRES flag that determines amount of output messages of fgmres INTEGER iOutFGMRES C FGMRES flag that indicates what fgmres wants us to do next @@ -75,29 +82,37 @@ _RL JFNKresidual _RL JFNKresidualKm1 C parameters to compute convergence criterion - _RL phi_e, alp_e, JFNKgamma_lin + _RL JFNKgamma_lin _RL FGMRESeps _RL JFNKtol -C +C backward differences extrapolation factors + _RL bdfFac, bdfAlpha +C _RL recip_deltaT LOGICAL JFNKconverged, krylovConverged LOGICAL writeNow CHARACTER*(MAX_LEN_MBUF) msgBuf -C + C u/vIceRes :: residual of sea-ice momentum equations _RL uIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) _RL vIceRes(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) -C vector version of the residuals - _RL resTmp (nVec,1,nSx,nSy) +C extra time level required for backward difference time stepping + _RL duIcNm1(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) + _RL dvIcNm1(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) C du/vIce :: ice velocity increment to be added to u/vIce _RL duIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) _RL dvIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) -C precomputed (= constant per Newton iteration) versions of +C precomputed (= constant per Newton iteration) versions of C zeta, eta, and DWATN, press _RL zetaPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) + _RL zetaZPre(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) _RL etaPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) _RL etaZPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) _RL dwatPre (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) +C work arrays + _RL rhs(nVec,nSx,nSy), sol(nVec,nSx,nSy) + _RL vv(nVec,im+1,nSx,nSy), w(nVec,im,nSx,nSy) + _RL wk1(nVec,nSx,nSy), wk2(nVec,nSx,nSy) CEOP C Initialise @@ -117,40 +132,62 @@ & DIFFERENT_MULTIPLE( SEAICE_monFreq, myTime, deltaTClock ) ) & iOutFGMRES=1 -C +C backward difference extrapolation factors + bdfFac = 0. _d 0 + IF ( SEAICEuseBDF2 ) THEN + IF ( myIter.EQ.nIter0 .AND. SEAICEmomStartBDF.EQ.0 ) THEN + bdfFac = 0. _d 0 + ELSE + bdfFac = 0.5 _d 0 + ENDIF + ENDIF + bdfAlpha = 1. _d 0 + bdfFac + DO bj=myByLo(myThid),myByHi(myThid) DO bi=myBxLo(myThid),myBxHi(myThid) - DO J=1-Oly,sNy+Oly - DO I=1-Olx,sNx+Olx + DO J=1-OLy,sNy+OLy + DO I=1-OLx,sNx+OLx uIceRes(I,J,bi,bj) = 0. _d 0 vIceRes(I,J,bi,bj) = 0. _d 0 duIce (I,J,bi,bj) = 0. _d 0 dvIce (I,J,bi,bj) = 0. _d 0 + ENDDO + ENDDO +C cycle ice velocities + DO J=1-OLy,sNy+OLy + DO I=1-OLx,sNx+OLx + duIcNm1(I,J,bi,bj) = uIce(I,J,bi,bj) * bdfAlpha + & + ( uIce(I,J,bi,bj) - uIceNm1(I,J,bi,bj) ) * bdfFac + dvIcNm1(I,J,bi,bj) = vIce(I,J,bi,bj) * bdfAlpha + & + ( vIce(I,J,bi,bj) - vIceNm1(I,J,bi,bj) ) * bdfFac uIceNm1(I,J,bi,bj) = uIce(I,J,bi,bj) vIceNm1(I,J,bi,bj) = vIce(I,J,bi,bj) ENDDO ENDDO +C As long as IMEX is not properly implemented leave this commented out +CML IF ( .NOT.SEAICEuseIMEX ) THEN C Compute things that do no change during the Newton iteration: -C sea-surface tilt and wind stress: -C FORCEX/Y0 - mass*(u/vIceNm1)/deltaT - DO J=1-Oly,sNy+Oly - DO I=1-Olx,sNx+Olx +C sea-surface tilt and wind stress: +C FORCEX/Y0 - mass*(1.5*u/vIceNm1+0.5*(u/vIceNm1-u/vIceNm2))/deltaT + DO J=1-OLy,sNy+OLy + DO I=1-OLx,sNx+OLx FORCEX(I,J,bi,bj) = FORCEX0(I,J,bi,bj) - & + seaiceMassU(I,J,bi,bj)*uIceNm1(I,J,bi,bj)*recip_deltaT + & + seaiceMassU(I,J,bi,bj)*duIcNm1(I,J,bi,bj)*recip_deltaT FORCEY(I,J,bi,bj) = FORCEY0(I,J,bi,bj) - & + seaiceMassV(I,J,bi,bj)*vIceNm1(I,J,bi,bj)*recip_deltaT + & + seaiceMassV(I,J,bi,bj)*dvIcNm1(I,J,bi,bj)*recip_deltaT ENDDO ENDDO +CML ENDIF ENDDO ENDDO C Start nonlinear Newton iteration: outer loop iteration - DO WHILE ( newtonIter.LT.SEAICEnewtonIterMax .AND. + DO WHILE ( newtonIter.LT.SEAICEnonLinIterMax .AND. & .NOT.JFNKconverged ) newtonIter = newtonIter + 1 C Compute initial residual F(u), (includes computation of global C variables DWATN, zeta, and eta) - IF ( newtonIter .EQ. 1 ) CALL SEAICE_JFNK_UPDATE( - I duIce, dvIce, + IF ( newtonIter .EQ. 1 ) CALL SEAICE_JFNK_UPDATE( + I duIce, dvIce, U uIce, vIce, JFNKresidual, O uIceRes, vIceRes, I newtonIter, myTime, myIter, myThid ) @@ -158,9 +195,10 @@ C constant for the preconditioner DO bj=myByLo(myThid),myByHi(myThid) DO bi=myBxLo(myThid),myBxHi(myThid) - DO j=1-Oly,sNy+Oly - DO i=1-Olx,sNx+Olx + DO j=1-OLy,sNy+OLy + DO i=1-OLx,sNx+OLx zetaPre(I,J,bi,bj) = zeta(I,J,bi,bj) + zetaZPre(I,J,bi,bj)= zetaZ(I,J,bi,bj) etaPre(I,J,bi,bj) = eta(I,J,bi,bj) etaZPre(I,J,bi,bj) = etaZ(I,J,bi,bj) dwatPre(I,J,bi,bj) = DWATN(I,J,bi,bj) @@ -170,18 +208,17 @@ ENDDO C compute convergence criterion for linear preconditioned FGMRES JFNKgamma_lin = JFNKgamma_lin_max - IF ( newtonIter.GT.1.AND.newtonIter.LE.100 + IF ( newtonIter.GT.1.AND.newtonIter.LE.SEAICE_JFNK_tolIter & .AND.JFNKresidual.LT.JFNKres_t ) THEN -C Eisenstat, 1996, equ.(2.6) - phi_e = 1. _d 0 - alp_e = 1. _d 0 - JFNKgamma_lin = phi_e*( JFNKresidual/JFNKresidualKm1 )**alp_e +C Eisenstat and Walker (1996), eq.(2.6) + JFNKgamma_lin = SEAICE_JFNKphi + & *( JFNKresidual/JFNKresidualKm1 )**SEAICE_JFNKalpha JFNKgamma_lin = min(JFNKgamma_lin_max, JFNKgamma_lin) JFNKgamma_lin = max(JFNKgamma_lin_min, JFNKgamma_lin) ENDIF C save the residual for the next iteration JFNKresidualKm1 = JFNKresidual -C + C The Krylov iteration using FGMRES, the preconditioner is LSOR C for now. The code is adapted from SEAICE_LSR, but heavily stripped C down. @@ -189,42 +226,69 @@ C in that routine krylovIter = 0 iCode = 0 -C + JFNKconverged = JFNKresidual.LT.JFNKtol -C + C do Krylov loop only if convergence is not reached -C + IF ( .NOT.JFNKconverged ) THEN -C + C start Krylov iteration (FGMRES) -C + krylovConverged = .FALSE. FGMRESeps = JFNKgamma_lin * JFNKresidual - DO WHILE ( .NOT.krylovConverged ) +C map first guess sol; it is zero because the solution is a correction + CALL SEAICE_MAP2VEC(nVec,duIce,dvIce,sol,.TRUE.,myThid) +C map rhs and change its sign because we are solving J*u = -F + CALL SEAICE_MAP2VEC(nVec,uIceRes,vIceRes,rhs,.TRUE.,myThid) + DO bj=myByLo(myThid),myByHi(myThid) + DO bi=myBxLo(myThid),myBxHi(myThid) + DO j=1,nVec + rhs(j,bi,bj) = - rhs(j,bi,bj) + ENDDO + ENDDO + ENDDO + DO WHILE ( .NOT.krylovConverged ) C solution vector sol = du/vIce C residual vector (rhs) Fu = u/vIceRes -C output work vectors wk1, -> input work vector wk2 +C output work vectors wk1, -> input work vector wk2 + +C map preconditioner results or Jacobian times vector, +C stored in du/vIce to wk2, for iCode=0, wk2 is set to zero, +C because du/vIce = 0 + CALL SEAICE_MAP2VEC(nVec,duIce,dvIce,wk2,.TRUE.,myThid) +C + CALL SEAICE_FGMRES (nVec,im,rhs,sol,ifgmres,krylovIter, + U vv,w,wk1,wk2, + I FGMRESeps,SEAICElinearIterMax,iOutFGMRES, + U iCode, + I myThid) C - CALL SEAICE_FGMRES_DRIVER( - I uIceRes, vIceRes, - U duIce, dvIce, iCode, - I FGMRESeps, iOutFGMRES, - I newtonIter, krylovIter, myTime, myIter, myThid ) + IF ( iCode .EQ. 0 ) THEN +C map sol(ution) vector to du/vIce + CALL SEAICE_MAP2VEC(nVec,duIce,dvIce,sol,.FALSE.,myThid) + ELSE +C map work vector to du/vIce to either compute a preconditioner +C solution (wk1=rhs) or a Jacobian times wk1 + CALL SEAICE_MAP2VEC(nVec,duIce,dvIce,wk1,.FALSE.,myThid) + ENDIF +C Fill overlaps in updated fields + CALL EXCH_UV_XY_RL( duIce, dvIce,.TRUE.,myThid) C FGMRES returns iCode either asking for an new preconditioned vector C or product of matrix (Jacobian) times vector. For iCode = 0, terminate C iteration IF (iCode.EQ.1) THEN -C Call preconditioner - IF ( SOLV_MAX_ITERS .GT. 0 ) - & CALL SEAICE_PRECONDITIONER( - U duIce, dvIce, - I zetaPre, etaPre, etaZpre, dwatPre, +C Call preconditioner + IF ( SEAICEpreconLinIter .GT. 0 ) + & CALL SEAICE_PRECONDITIONER( + U duIce, dvIce, + I zetaPre, etaPre, etaZpre, zetaZpre, dwatPre, I newtonIter, krylovIter, myTime, myIter, myThid ) ELSEIF (iCode.GE.2) THEN C Compute Jacobian times vector CALL SEAICE_JACVEC( I uIce, vIce, uIceRes, vIceRes, - U duIce, dvIce, + U duIce, dvIce, I newtonIter, krylovIter, myTime, myIter, myThid ) ENDIF krylovConverged = iCode.EQ.0 @@ -234,9 +298,9 @@ C some output diagnostics IF ( debugLevel.GE.debLevA ) THEN _BEGIN_MASTER( myThid ) - totalNewtonItersLoc = - & SEAICEnewtonIterMax*(myIter-nIter0)+newtonIter - WRITE(msgBuf,'(2A,2(1XI6),2E12.5)') + totalNewtonItersLoc = + & SEAICEnonLinIterMax*(myIter-nIter0)+newtonIter + WRITE(msgBuf,'(2A,2(1XI6),2E12.5)') & ' S/R SEAICE_JFNK: Newton iterate / total, ', & 'JFNKgamma_lin, initial norm = ', & newtonIter, totalNewtonItersLoc, @@ -244,34 +308,39 @@ CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) WRITE(msgBuf,'(3(A,I6))') - & ' S/R SEAICE_JFNK: Newton iterate / total = ',newtonIter, + & ' S/R SEAICE_JFNK: Newton iterate / total = ',newtonIter, & ' / ', totalNewtonItersLoc, & ', Nb. of FGMRES iterations = ', krylovIter CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) _END_MASTER( myThid ) ENDIF - IF ( krylovIter.EQ.SEAICEkrylovIterMax ) THEN + IF ( krylovIter.EQ.SEAICElinearIterMax ) THEN krylovFails = krylovFails + 1 ENDIF -C Set the stopping criterion for the Newton iteration - IF ( newtonIter .EQ. 1 ) JFNKtol=JFNKgamma_nonlin*JFNKresidual +C Set the stopping criterion for the Newton iteration and the +C criterion for the transition from accurate to approximate FGMRES + IF ( newtonIter .EQ. 1 ) THEN + JFNKtol=SEAICEnonLinTol*JFNKresidual + IF ( JFNKres_tFac .NE. UNSET_RL ) + & JFNKres_t = JFNKresidual * JFNKres_tFac + ENDIF C Update linear solution vector and return to Newton iteration C Do a linesearch if necessary, and compute a new residual. C Note that it should be possible to do the following operations C at the beginning of the Newton iteration, thereby saving us from C the extra call of seaice_jfnk_update, but unfortunately that C changes the results, so we leave the stuff here for now. - CALL SEAICE_JFNK_UPDATE( - I duIce, dvIce, + CALL SEAICE_JFNK_UPDATE( + I duIce, dvIce, U uIce, vIce, JFNKresidual, O uIceRes, vIceRes, I newtonIter, myTime, myIter, myThid ) C reset du/vIce here instead of setting sol = 0 in seaice_fgmres_driver DO bj=myByLo(myThid),myByHi(myThid) DO bi=myBxLo(myThid),myBxHi(myThid) - DO J=1-Oly,sNy+Oly - DO I=1-Olx,sNx+Olx + DO J=1-OLy,sNy+OLy + DO I=1-OLx,sNx+OLx duIce(I,J,bi,bj)= 0. _d 0 dvIce(I,J,bi,bj)= 0. _d 0 ENDDO @@ -281,9 +350,9 @@ ENDIF C end of Newton iterate ENDDO -C + C-- Output diagnostics -C + IF ( SEAICE_monFreq .GT. 0. _d 0 ) THEN C Count iterations totalJFNKtimeSteps = totalJFNKtimeSteps + 1 @@ -291,16 +360,16 @@ totalKrylovIters = totalKrylovIters + totalKrylovItersLoc C Record failure totalKrylovFails = totalKrylovFails + krylovFails - IF ( newtonIter .EQ. SEAICEnewtonIterMax ) THEN - totalNewtonFails = totalNewtonFails + 1 + IF ( newtonIter .EQ. SEAICEnonLinIterMax ) THEN + totalNewtonFails = totalNewtonFails + 1 ENDIF ENDIF C Decide whether it is time to dump and reset the counter writeNow = DIFFERENT_MULTIPLE(SEAICE_monFreq, - & myTime+deltaTClock, deltaTClock) + & myTime+deltaTClock, deltaTClock) #ifdef ALLOW_CAL IF ( useCAL ) THEN - CALL CAL_TIME2DUMP( + CALL CAL_TIME2DUMP( I zeroRL, SEAICE_monFreq, deltaTClock, U writeNow, I myTime+deltaTclock, myIter+1, myThid ) @@ -308,49 +377,49 @@ #endif IF ( writeNow ) THEN _BEGIN_MASTER( myThid ) - WRITE(msgBuf,'(A)') + WRITE(msgBuf,'(A)') &' // =======================================================' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) WRITE(msgBuf,'(A)') ' // Begin JFNK statistics' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A)') + WRITE(msgBuf,'(A)') &' // =======================================================' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: time step = ', myIter+1 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: Nb. of time steps = ', totalJFNKtimeSteps CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: Nb. of Newton steps = ', totalNewtonIters CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: Nb. of Krylov steps = ', totalKrylovIters CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: Nb. of Newton failures = ', totalNewtonFails CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' %JFNK_MON: Nb. of Krylov failures = ', totalKrylovFails CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A)') + WRITE(msgBuf,'(A)') &' // =======================================================' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) WRITE(msgBuf,'(A)') ' // End JFNK statistics' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) - WRITE(msgBuf,'(A)') + WRITE(msgBuf,'(A)') &' // =======================================================' CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, & SQUEEZE_RIGHT, myThid ) @@ -365,9 +434,9 @@ C Print more debugging information IF ( debugLevel.GE.debLevA ) THEN - IF ( newtonIter .EQ. SEAICEnewtonIterMax ) THEN + IF ( newtonIter .EQ. SEAICEnonLinIterMax ) THEN _BEGIN_MASTER( myThid ) - WRITE(msgBuf,'(A,I10)') + WRITE(msgBuf,'(A,I10)') & ' S/R SEAICE_JFNK: JFNK did not converge in timestep ', & myIter+1 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, @@ -376,7 +445,7 @@ ENDIF IF ( krylovFails .GT. 0 ) THEN _BEGIN_MASTER( myThid ) - WRITE(msgBuf,'(A,I4,A,I10)') + WRITE(msgBuf,'(A,I4,A,I10)') & ' S/R SEAICE_JFNK: FGMRES did not converge ', & krylovFails, ' times in timestep ', myIter+1 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, @@ -384,7 +453,7 @@ _END_MASTER( myThid ) ENDIF _BEGIN_MASTER( myThid ) - WRITE(msgBuf,'(A,I6,A,I10)') + WRITE(msgBuf,'(A,I6,A,I10)') & ' S/R SEAICE_JFNK: Total number FGMRES iterations = ', & totalKrylovItersLoc, ' in timestep ', myIter+1 CALL PRINT_MESSAGE( msgBuf, standardMessageUnit, @@ -400,8 +469,8 @@ C !ROUTINE: SEAICE_JFNK_UPDATE C !INTERFACE: - SUBROUTINE SEAICE_JFNK_UPDATE( - I duIce, dvIce, + SUBROUTINE SEAICE_JFNK_UPDATE( + I duIce, dvIce, U uIce, vIce, JFNKresidual, O uIceRes, vIceRes, I newtonIter, myTime, myIter, myThid ) @@ -460,11 +529,11 @@ _RL resLoc, facLS LOGICAL doLineSearch C nVec :: size of the input vector(s) -C vector version of the residuals +C resTmp :: vector version of the residuals INTEGER nVec PARAMETER ( nVec = 2*sNx*sNy ) _RL resTmp (nVec,1,nSx,nSy) -C + CHARACTER*(MAX_LEN_MBUF) msgBuf CEOP @@ -474,23 +543,11 @@ facLS = 1. _d 0 doLineSearch = .TRUE. DO WHILE ( doLineSearch ) -C Determine, if we need more iterations - doLineSearch = resLoc .GE. JFNKresidual -C Limit the maximum number of iterations arbitrarily to four - doLineSearch = doLineSearch .AND. l .LE. 4 -C For the first iteration du/vIce = 0 and there will be no -C improvement of the residual possible, so we do only the first -C iteration - IF ( newtonIter .EQ. 1 ) doLineSearch = .FALSE. -C Only start a linesearch after some Newton iterations - IF ( newtonIter .LE. SEAICE_JFNK_lsIter ) doLineSearch = .FALSE. -C Increment counter - l = l + 1 C Create update DO bj=myByLo(myThid),myByHi(myThid) DO bi=myBxLo(myThid),myBxHi(myThid) - DO J=1-Oly,sNy+Oly - DO I=1-Olx,sNx+Olx + DO J=1-OLy,sNy+OLy + DO I=1-OLx,sNx+OLx uIce(I,J,bi,bj) = uIce(I,J,bi,bj)+facLS*duIce(I,J,bi,bj) vIce(I,J,bi,bj) = vIce(I,J,bi,bj)+facLS*dvIce(I,J,bi,bj) ENDDO @@ -499,19 +556,31 @@ ENDDO C Compute current residual F(u), (includes re-computation of global C variables DWATN, zeta, and eta, i.e. they are different after this) - CALL SEAICE_CALC_RESIDUAL( - I uIce, vIce, - O uIceRes, vIceRes, + CALL SEAICE_CALC_RESIDUAL( + I uIce, vIce, + O uIceRes, vIceRes, I newtonIter, 0, myTime, myIter, myThid ) C Important: Compute the norm of the residual using the same scalar C product that SEAICE_FGMRES does CALL SEAICE_MAP2VEC(nVec,uIceRes,vIceRes,resTmp,.TRUE.,myThid) CALL SEAICE_SCALPROD(nVec,1,1,1,resTmp,resTmp,resLoc,myThid) resLoc = SQRT(resLoc) +C Determine, if we need more iterations + doLineSearch = resLoc .GE. JFNKresidual +C Limit the maximum number of iterations arbitrarily to four + doLineSearch = doLineSearch .AND. l .LT. 4 +C For the first iteration du/vIce = 0 and there will be no +C improvement of the residual possible, so we do only the first +C iteration + IF ( newtonIter .EQ. 1 ) doLineSearch = .FALSE. +C Only start a linesearch after some Newton iterations + IF ( newtonIter .LE. SEAICE_JFNK_lsIter ) doLineSearch = .FALSE. +C Increment counter + l = l + 1 C some output diagnostics IF ( debugLevel.GE.debLevA .AND. doLineSearch ) THEN _BEGIN_MASTER( myThid ) - WRITE(msgBuf,'(2A,2(1XI6),3E12.5)') + WRITE(msgBuf,'(2A,2(1XI6),3E12.5)') & ' S/R SEAICE_JFNK_UPDATE: Newton iter, LSiter, ', & 'facLS, JFNKresidual, resLoc = ', & newtonIter, l, facLS, JFNKresidual, resLoc @@ -527,7 +596,7 @@ C This is the new residual JFNKresidual = resLoc -#endif /* SEAICE_ALLOW_DYNAMICS and SEAICE_CGRID and SEAICE_ALLOW_JFNK */ +#endif /* SEAICE_ALLOW_JFNK */ RETURN END