capac.cpp

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#include <../../nrnconf.h>
/* /local/src/master/nrn/src/nrnoc/capac.cpp,v 1.6 1998/11/25 19:14:28 hines Exp */

#include    "section.h"
#include    "membdef.h"
#include    "nrniv_mf.h"


static const char *mechanism[] = {"0", "capacitance", "cm", 0, "i_cap", 0, 0};
static void cap_alloc(Prop *);
static void cap_init(NrnThread *, Memb_list *, int);

#define nparm 2
extern "C" void capac_reg_(void) {
    int mechtype;
    /* all methods deal with capacitance in special ways */
    register_mech(mechanism, cap_alloc, (Pvmi) 0, (Pvmi) 0, (Pvmi) 0, cap_init, -1, 1);
    mechtype = nrn_get_mechtype(mechanism[1]);
    hoc_register_prop_size(mechtype, nparm, 0);
}

#define cm  vdata[i][0]
#define i_cap  vdata[i][1]

/*
cj is analogous to 1/dt for cvode and daspk
for fixed step second order it is 2/dt and
for pure implicit fixed step it is 1/dt
It used to be static but is now a thread data variable
*/

void nrn_cap_jacob(NrnThread *_nt, Memb_list *ml) {
    int count = ml->nodecount;
    Node **vnode = ml->nodelist;
    double **vdata = ml->data;
    int i;
    double cfac = .001 * _nt->cj;
#if CACHEVEC
    if (use_cachevec) {
        int *ni = ml->nodeindices;
        for (i = 0; i < count; i++) {
            VEC_D(ni[i]) += cfac * cm;
        }
    } else
#endif /* CACHEVEC */
    {
        for (i = 0; i < count; ++i) {
            NODED(vnode[i]) += cfac * cm;
        }
    }
}

static void cap_init(NrnThread *_nt, Memb_list *ml, int type) {
    int count = ml->nodecount;
    double **vdata = ml->data;
    int i;
    for (i = 0; i < count; ++i) {
        i_cap = 0;
    }
}

void nrn_capacity_current(NrnThread *_nt, Memb_list *ml) {
    int count = ml->nodecount;
    Node **vnode = ml->nodelist;
    double **vdata = ml->data;
    int i;
    double cfac = .001 * _nt->cj;
    /* since rhs is dvm for a full or half implicit step */
    /* (nrn_update_2d() replaces dvi by dvi-dvx) */
    /* no need to distinguish secondorder */
#if CACHEVEC
    if (use_cachevec) {
        int *ni = ml->nodeindices;
        for (i = 0; i < count; i++) {
            i_cap = cfac * cm * VEC_RHS(ni[i]);
        }
    } else
#endif /* CACHEVEC */
    {
        for (i = 0; i < count; ++i) {
            i_cap = cfac * cm * NODERHS(vnode[i]);
        }
    }
}

#if CVODE

void nrn_mul_capacity(NrnThread *_nt, Memb_list *ml) {
    int count = ml->nodecount;
    Node **vnode = ml->nodelist;
    double **vdata = ml->data;
    int i;
    double cfac = .001 * _nt->cj;
#if CACHEVEC
    if (use_cachevec) {
        int *ni = ml->nodeindices;
        for (i = 0; i < count; i++) {
            VEC_RHS(ni[i]) *= cfac * cm;
        }
    } else
#endif /* CACHEVEC */
    {
        for (i = 0; i < count; ++i) {
            NODERHS(vnode[i]) *= cfac * cm;
        }
    }
}

void nrn_div_capacity(NrnThread *_nt, Memb_list *ml) {
    int count = ml->nodecount;
    Node **vnode = ml->nodelist;
    double **vdata = ml->data;
    int i;
#if CACHEVEC
    if (use_cachevec) {
        int *ni = ml->nodeindices;
        for (i = 0; i < count; i++) {
            i_cap = VEC_RHS(ni[i]);
            VEC_RHS(ni[i]) /= 1.e-3 * cm;
        }
    } else
#endif /* CACHEVEC */
    {
        for (i = 0; i < count; ++i) {
            i_cap = NODERHS(vnode[i]);
            NODERHS(vnode[i]) /= 1.e-3 * cm;
        }
    }
    if (_nt->_nrn_fast_imem) {
        double *p = _nt->_nrn_fast_imem->_nrn_sav_rhs;
        for (i = 0; i < count; ++i) {
            p[vnode[i]->v_node_index] += i_cap;
        }
    }
}

#endif /*CVODE*/

/* the rest can be constructed automatically from the above info*/

static void cap_alloc(Prop *p) {
    double *pd;
    pd = nrn_prop_data_alloc(CAP, nparm, p);
    pd[0] = DEF_cm;    /*default capacitance/cm^2*/
    p->param = pd;
    p->param_size = nparm;
}