static void WebRatesB(realtype x, realtype y, realtype t, realtype c[], realtype cB[],
realtype rate[], realtype rateB[], WebData wdata)
{
int i, j, ns;
realtype fac, *bcoef;
realtype (*acoef)[NS];
ns = wdata->ns;
acoef = wdata->acoef;
bcoef = wdata->bcoef;
fac = ONE + ALPH*x*y;
for (i = 0; i < ns; i++)
rate[i] = bcoef[i]*fac;
for (j = 0; j < ns; j++)
for (i = 0; i < ns; i++)
rate[i] += acoef[i][j]*c[j];
for (i = 0; i < ns; i++) {
rateB[i] = cB[i]*rate[i];
rate[i] = c[i]*rate[i];
}
for (j = 0; j < ns; j++)
for (i = 0; i < ns; i++)
rateB[i] += acoef[j][i]*c[j]*cB[j];
}
static void InitUserData(WebData wdata)
{
int i, j, ns;
realtype *bcoef, *diff, *cox, *coy, dx, dy;
realtype (*acoef)[NS];
acoef = wdata->acoef;
bcoef = wdata->bcoef;
diff = wdata->diff;
cox = wdata->cox;
coy = wdata->coy;
ns = wdata->ns = NS;
for (j = 0; j < NS; j++) {
for (i = 0; i < NS; i++) acoef[i][j] = 0.;
}
for (j = 0; j < NP; j++) {
for (i = 0; i < NP; i++) {
acoef[NP+i][j] = EE;
acoef[i][NP+j] = -GG;
}
acoef[j][j] = -AA;
acoef[NP+j][NP+j] = -AA;
bcoef[j] = BB;
bcoef[NP+j] = -BB;
diff[j] = DPREY;
diff[NP+j] = DPRED;
}
/* Set remaining problem parameters */
wdata->mxns = MXNS;
dx = wdata->dx = DX;
dy = wdata->dy = DY;
for (i = 0; i < ns; i++) {
cox[i] = diff[i]/SQR(dx);
coy[i] = diff[i]/SQR(dy);
}
/* Set remaining method parameters */
wdata->mp = MP;
wdata->mq = MQ;
wdata->mx = MX;
wdata->my = MY;
wdata->srur = SQRT(UNIT_ROUNDOFF);
wdata->mxmp = MXMP;
wdata->ngrp = NGRP;
wdata->ngx = NGX;
wdata->ngy = NGY;
SetGroups(MX, NGX, wdata->jgx, wdata->jigx, wdata->jxr);
SetGroups(MY, NGY, wdata->jgy, wdata->jigy, wdata->jyr);
}
/*
This routine computes the interaction rates for the species
c_1, ... ,c_ns (stored in c[0],...,c[ns-1]), at one spatial point
and at time t.
*/
static void WebRates(realtype x, realtype y, realtype t, realtype c[],
realtype rate[], WebData wdata)
{
int i, j, ns;
realtype fac, *bcoef;
realtype (*acoef)[NS];
ns = wdata->ns;
acoef = wdata->acoef;
bcoef = wdata->bcoef;
for (i = 0; i < ns; i++)
rate[i] = ZERO;
for (j = 0; j < ns; j++)
for (i = 0; i < ns; i++)
rate[i] += c[j] * acoef[i][j];
fac = ONE + ALPH*x*y;
for (i = 0; i < ns; i++)
rate[i] = c[i]*(bcoef[i]*fac + rate[i]);
}