#ifndef lint
static char 
*rcs="$Header: /mit/hst/src/sim/RCS/estimate.c,v 2.1 90/08/18 18:40:12 tldavis Exp $";
#endif

/* R. Sah	August 1983
 * G. Moody	18 December 1984
 * T. Davis     June 1985
 * Copyright 1988 Timothy L. Davis
 * $Source: /mit/hst/src/sim/RCS/estimate.c,v $
 * Estimate initial pressures at the six nodes in the model by setting up an
 * 8x8 system of linear equations.  NOTE: uses lineqs() in libm.a.
 */

#include "CVDefs.h"

extern double Tsystole(); /* from eqns.c */ 

estimate(p,x)
SIMULATION *p;
double x[];

{
  double a[8][8], b[8];
  double T, Tsys, Tdias;
  
        
        T = 60./p->hr;
        Tsys = Tsystole(p->hr);
        Tdias = T - Tsys;

	a[0][0] = p->Cldias;
	a[1][0] = 0.;
	a[2][0] = p->Crdias;
	a[3][0] = 0.;
	a[4][0] = p->Ca;
	a[5][0] = p->Cv;
	a[6][0] = p->CPa;
	a[7][0] = p->CPv;
	
	a[0][1] = p->Cldias;
	a[1][1] = -p->Clsys;
	a[2][1] = -p->Crdias;
	a[3][1] = p->Crsys;
	a[4][1] = 0.;
	a[5][1] = 0.;
	a[6][1] = 0.;
	a[7][1] = 0.;

	a[0][2] = -p->Cldias*p->Rv/Tdias;
	a[1][2] = p->Clsys*(p->Rv)/Tdias;
	a[2][2] = -1.;
	a[3][2] = 0.;
	a[4][2] = 0.;
	a[5][2] = 1.;
	a[6][2] = 0.;
	a[7][2] = 0.;

	a[0][3] = -p->Cldias*(p->Rro)/Tsys;
	a[1][3] = p->Clsys*(p->Rro)/Tsys;
	a[2][3] = 0.;
	a[3][3] = 1.;
	a[4][3] = 0.;
	a[5][3] = 0.;
	a[6][3] = -1.;
	a[7][3] = 0.;

	a[0][4] = -p->Cldias*(p->Rlo)/Tsys;
	a[1][4] = 1. + p->Clsys*(p->Rlo)/Tsys;
	a[2][4] = 0.;
	a[3][4] = 0.;
	a[4][4] = -1.;
	a[5][4] = 0.;
	a[6][4] = 0.;
	a[7][4] = 0.;

	a[0][5] = -p->Cldias*(p->Ra)/T;
	a[1][5] = p->Clsys*(p->Ra)/T;
	a[2][5] = 0.;
	a[3][5] = 0.;
	a[4][5] = 1.;
	a[5][5] = -1.;
	a[6][5] = 0.;
	a[7][5] = 0.;

	a[0][6] = -p->Cldias*(p->RPv)/T;
	a[1][6] = p->Clsys*(p->RPv)/T;
	a[2][6] = 0.;
	a[3][6] = 0.;
	a[4][6] = 0.;
	a[5][6] = 0.;
	a[6][6] = 1.;
	a[7][6] = -1.;

	a[0][7] = -1.-p->Cldias*(p->Rli)/Tdias;
	a[1][7] = p->Clsys*(p->Rli)/Tdias;
	a[2][7] = 0.;
	a[3][7] = 0.;
	a[4][7] = 0.;
	a[5][7] = 0.;
	a[6][7] = 0.;
	a[7][7] = 1.;

	b[0] = p->bv - (p->Va0+p->Vv0+p->Vr0+p->VPa0+
			p->VPv0+p->Vl0)
	             + p->pth*
			    (p->Cldias+p->Crdias+p->CPa+p->CPv);
	b[1] = p->pth*(p->Cldias-p->Clsys-p->Crdias+p->Crsys);
	b[4] = p->pth*(p->Rlo)*(p->Clsys-p->Cldias)/Tsys;
	b[3] = p->pth*(p->Rro)*(p->Clsys-p->Cldias)/Tsys;
	b[5] = p->pth*(p->Ra )*(p->Clsys-p->Cldias)/T;
	b[6] = p->pth*(p->RPv)*(p->Clsys-p->Cldias)/T;
	b[2] = p->pth*(p->Rv )*(p->Clsys-p->Cldias)/Tdias;
	b[7] = p->pth*(p->Rli)*(p->Clsys-p->Cldias)/Tdias;
	
	lineqs(a,b);

	xpl=b[0]; /* put the estimated pressure vals in x[] using macros */
	xpr=b[2];
	xpa=b[4];
	xpv=b[5];
	xpPa=b[6];
	xpPv=b[7];
        xt  = 0.0;
        xCl = p->Cldias;
        xCr = p->Crdias;
        x[9] = 0.0;
}