void FKIN_LAPACKBANDSETJAC(int *flag, int *ier)
{
if (*flag == 0) {
*ier = KINDlsSetBandJacFn(KIN_kinmem, NULL);
}
else {
*ier = KINDlsSetBandJacFn(KIN_kinmem, FKINLapackBandJac);
}
return;
}
int main()
{
realtype fnormtol, fnorm;
N_Vector y, scale;
int flag;
void *kmem;
y = scale = NULL;
kmem = NULL;
/* -------------------------
* Print problem description
* ------------------------- */
printf("\n2D elliptic PDE on unit square\n");
printf(" d^2 u / dx^2 + d^2 u / dy^2 = u^3 - u + 2.0\n");
printf(" + homogeneous Dirichlet boundary conditions\n\n");
printf("Solution method: Anderson accelerated Picard iteration with band linear solver.\n");
printf("Problem size: %2ld x %2ld = %4ld\n",
(long int) NX, (long int) NY, (long int) NEQ);
/* --------------------------------------
* Create vectors for solution and scales
* -------------------------------------- */
y = N_VNew_Serial(NEQ);
if (check_flag((void *)y, "N_VNew_Serial", 0)) return(1);
scale = N_VNew_Serial(NEQ);
if (check_flag((void *)scale, "N_VNew_Serial", 0)) return(1);
/* ----------------------------------------------------------------------------------
* Initialize and allocate memory for KINSOL, set parametrs for Anderson acceleration
* ---------------------------------------------------------------------------------- */
kmem = KINCreate();
if (check_flag((void *)kmem, "KINCreate", 0)) return(1);
/* y is used as a template */
/* Use acceleration with up to 3 prior residuals */
flag = KINSetMAA(kmem, 3);
if (check_flag(&flag, "KINSetMAA", 1)) return(1);
flag = KINInit(kmem, func, y);
if (check_flag(&flag, "KINInit", 1)) return(1);
/* -------------------
* Set optional inputs
* ------------------- */
/* Specify stopping tolerance based on residual */
fnormtol = FTOL;
flag = KINSetFuncNormTol(kmem, fnormtol);
if (check_flag(&flag, "KINSetFuncNormTol", 1)) return(1);
/* -------------------------
* Attach band linear solver
* ------------------------- */
flag = KINBand(kmem, NEQ, NX, NX);
if (check_flag(&flag, "KINBand", 1)) return(1);
flag = KINDlsSetBandJacFn(kmem, jac);
if (check_flag(&flag, "KINDlsBandJacFn", 1)) return(1);
/* -------------
* Initial guess
* ------------- */
N_VConst_Serial(ZERO, y);
IJth(NV_DATA_S(y), 2, 2) = ONE;
/* ----------------------------
* Call KINSol to solve problem
* ---------------------------- */
/* No scaling used */
N_VConst_Serial(ONE,scale);
/* Call main solver */
flag = KINSol(kmem, /* KINSol memory block */
y, /* initial guess on input; solution vector */
KIN_PICARD, /* global strategy choice */
scale, /* scaling vector, for the variable cc */
scale); /* scaling vector for function values fval */
if (check_flag(&flag, "KINSol", 1)) return(1);
/* ------------------------------------
* Print solution and solver statistics
* ------------------------------------ */
/* Get scaled norm of the system function */
flag = KINGetFuncNorm(kmem, &fnorm);
if (check_flag(&flag, "KINGetfuncNorm", 1)) return(1);
printf("\nComputed solution (||F|| = %g):\n\n",fnorm);
PrintOutput(y);
PrintFinalStats(kmem);
/* -----------
* Free memory
* ----------- */
N_VDestroy_Serial(y);
N_VDestroy_Serial(scale);
KINFree(&kmem);
return(0);
}
