ngspice/src/frontend/linear.c

101 lines
3.0 KiB
C

/**********
Copyright 1990 Regents of the University of California. All rights reserved.
Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
**********/
#include "ngspice/ngspice.h"
#include "ngspice/cpdefs.h"
#include "ngspice/ftedefs.h"
#include "ngspice/dvec.h"
#include "circuits.h"
#include "linear.h"
#include "interp.h"
/* Interpolate all the vectors in a plot to a linear time scale, which
* we determine by looking at the transient parameters in the CKT struct.
*/
void
com_linearize(wordlist *wl)
{
double tstart, tstop, tstep, d;
struct plot *new, *old;
struct dvec *newtime, *v;
struct dvec *oldtime;
int len, i;
char buf[BSIZE_SP];
if (!ft_curckt || !ft_curckt->ci_ckt ||
!if_tranparams(ft_curckt, &tstart, &tstop, &tstep)) {
fprintf(cp_err,
"Error: can't get transient parameters from circuit\n");
return;
}
if (((tstop - tstart) * tstep <= 0.0) || ((tstop - tstart) < tstep)) {
fprintf(cp_err,
"Error: bad parameters -- start = %G, stop = %G, step = %G\n",
tstart, tstop, tstep);
return;
}
if (!plot_cur || !plot_cur->pl_dvecs || !plot_cur->pl_scale) {
fprintf(cp_err, "Error: no vectors available\n");
return;
}
if (!isreal(plot_cur->pl_scale)) {
fprintf(cp_err, "Error: non-real time scale for %s\n",
plot_cur->pl_typename);
return;
}
if (!ciprefix("tran", plot_cur->pl_typename)) {
fprintf(cp_err, "Error: plot must be a transient analysis\n");
return;
}
old = plot_cur;
oldtime = old->pl_scale;
new = plot_alloc("transient");
(void) sprintf(buf, "%s (linearized)", old->pl_name);
new->pl_name = copy(buf);
new->pl_title = copy(old->pl_title);
new->pl_date = copy(old->pl_date);
new->pl_next = plot_list;
plot_new(new);
plot_setcur(new->pl_typename);
plot_list = new;
len = (int)((tstop - tstart) / tstep + 1.5);
newtime = alloc(struct dvec);
newtime->v_name = copy(oldtime->v_name);
newtime->v_type = oldtime->v_type;
newtime->v_flags = oldtime->v_flags;
newtime->v_flags |= VF_PERMANENT;
newtime->v_length = len;
newtime->v_plot = new;
newtime->v_realdata = TMALLOC(double, len);
for (i = 0, d = tstart; i < len; i++, d += tstep)
newtime->v_realdata[i] = d;
new->pl_scale = new->pl_dvecs = newtime;
if (wl) {
while (wl) {
v = vec_fromplot(wl->wl_word, old);
if (!v) {
fprintf(cp_err, "Error: no such vector %s\n",
wl->wl_word);
wl = wl->wl_next;
continue;
}
lincopy(v, newtime->v_realdata, len, oldtime);
wl = wl->wl_next;
}
} else {
for (v = old->pl_dvecs; v; v = v->v_next) {
if (v == old->pl_scale)
continue;
lincopy(v, newtime->v_realdata, len, oldtime);
}
}
return;
}