You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

81 lines
2.4 KiB

/**********
Copyright 1990 Regents of the University of California. All rights reserved.
Author: 1985 Thomas L. Quarles
**********/
/* NIintegrate(ckt,geq,ceq,cap,qcap)
* integrate the specified capacitor - method and order in the
* ckt structure, ccap follows qcap.
*/
#include "ngspice.h"
#include "cktdefs.h"
#include "sperror.h"
#include "niinteg.h"
#define ccap qcap+1
int
NIintegrate(CKTcircuit *ckt, double *geq, double *ceq, double cap, int qcap)
{
static char *ordmsg = "Illegal integration order";
static char *methodmsg = "Unknown integration method";
switch(ckt->CKTintegrateMethod) {
case TRAPEZOIDAL:
switch(ckt->CKTorder) {
case 1:
*(ckt->CKTstate0+ccap) = ckt->CKTag[0] * (*(ckt->CKTstate0+qcap))
+ ckt->CKTag[1] * (*(ckt->CKTstate1+qcap));
break;
case 2:
*(ckt->CKTstate0+ccap) = - *(ckt->CKTstate1+ccap) * ckt->CKTag[1] +
ckt->CKTag[0] *
( *(ckt->CKTstate0+qcap) - *(ckt->CKTstate1+qcap) );
break;
default:
errMsg = MALLOC(strlen(ordmsg)+1);
strcpy(errMsg,ordmsg);
return(E_ORDER);
}
break;
case GEAR:
*(ckt->CKTstate0+ccap)=0;
switch(ckt->CKTorder) {
case 6:
*(ckt->CKTstate0+ccap) += ckt->CKTag[6]* *(ckt->CKTstate6+qcap);
/* fall through */
case 5:
*(ckt->CKTstate0+ccap) += ckt->CKTag[5]* *(ckt->CKTstate5+qcap);
/* fall through */
case 4:
*(ckt->CKTstate0+ccap) += ckt->CKTag[4]* *(ckt->CKTstate4+qcap);
/* fall through */
case 3:
*(ckt->CKTstate0+ccap) += ckt->CKTag[3]* *(ckt->CKTstate3+qcap);
/* fall through */
case 2:
*(ckt->CKTstate0+ccap) += ckt->CKTag[2]* *(ckt->CKTstate2+qcap);
/* fall through */
case 1:
*(ckt->CKTstate0+ccap) += ckt->CKTag[1]* *(ckt->CKTstate1+qcap);
*(ckt->CKTstate0+ccap) += ckt->CKTag[0]* *(ckt->CKTstate0+qcap);
break;
default:
return(E_ORDER);
}
break;
default:
errMsg = MALLOC(strlen(methodmsg)+1);
strcpy(errMsg,methodmsg);
return(E_METHOD);
}
*ceq = *(ckt->CKTstate0+ccap) - ckt->CKTag[0] * *(ckt->CKTstate0+qcap);
*geq = ckt->CKTag[0] * cap;
return(OK);
}