realtype N_VMinQuotient_SensWrapper(N_Vector num, N_Vector denom)
{
int i;
realtype min, tmp;
min = N_VMinQuotient(NV_VEC_SW(num,0), NV_VEC_SW(denom,0));
for (i=1; i < NV_NVECS_SW(num); i++) {
tmp = N_VMinQuotient(NV_VEC_SW(num,i), NV_VEC_SW(denom,i));
if (tmp < min) min = tmp;
}
return(min);
}
static int IDALineSrch(IDAMem IDA_mem, realtype *delnorm, realtype *fnorm)
{
booleantype conOK;
int retval;
realtype f1norm, fnormp, f1normp, ratio, lambda, minlam, slpi;
N_Vector mc;
/* Initialize work space pointers, f1norm, ratio.
(Use of mc in constraint check does not conflict with ypnew.) */
mc = ee;
dtemp = phi[3];
ynew = tempv2;
ypnew = ee;
f1norm = (*fnorm)*(*fnorm)*HALF;
ratio = ONE;
/* If there are constraints, check and reduce step if necessary. */
if(constraintsSet) {
/* Update y and check constraints. */
IDANewy(IDA_mem);
conOK = N_VConstrMask(constraints, ynew, mc);
if(!conOK) {
/* Not satisfied. Compute scaled step to satisfy constraints. */
N_VProd(mc, delta, dtemp);
ratio = PT99*N_VMinQuotient(yy0, dtemp);
(*delnorm) *= ratio;
if((*delnorm) <= steptol) return(IC_CONSTR_FAILED);
N_VScale(ratio, delta, delta);
}
} /* End of constraints check */
slpi = -TWO*f1norm*ratio;
minlam = steptol/(*delnorm);
lambda = ONE;
/* In IDA_Y_INIT case, set ypnew = yp0 (fixed) for linesearch. */
if(icopt == IDA_Y_INIT) N_VScale(ONE, yp0, ypnew);
/* Loop on linesearch variable lambda. */
loop {
/* Get new (y,y') = (ynew,ypnew) and norm of new function value. */
IDANewyyp(IDA_mem, lambda);
retval = IDAfnorm(IDA_mem, &fnormp);
if(retval != IDA_SUCCESS) return(retval);
/* If lsoff option is on, break out. */
if(lsoff) break;
/* Do alpha-condition test. */
f1normp = fnormp*fnormp*HALF;
if(f1normp <= f1norm + ALPHALS*slpi*lambda) break;
if(lambda < minlam) return(IC_LINESRCH_FAILED);
lambda /= TWO;
nbacktr++;
} /* End of breakout linesearch loop */
/* Update yy0, yp0, and fnorm, then return. */
N_VScale(ONE, ynew, yy0);
if(icopt == IDA_YA_YDP_INIT) N_VScale(ONE, ypnew, yp0);
*fnorm = fnormp;
return(IDA_SUCCESS);
}
