sim3cms.c File Reference

Simulation of 3-tissue CM with compartments in series. More...

#include "tpcclibConfig.h"
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <string.h>
#include "tpccm.h"

Go to the source code of this file.

Functions
int	simC3s (double *t, double *ca, const int nr, double k1, double k2, double k3, double k4, double k5, double k6, double *ct, double *cta, double *ctb, double *ctc)
int	simC3vs (double *t, double *ca, double *cb, const int nr, const double k1, const double k2, const double k3, const double k4, const double k5, const double k6, const double f, const double vb, const double fa, const int vvm, double *cpet, double *cta, double *ctb, double *ctc, double *ctab, double *ctvb)

Detailed Description

Simulation of 3-tissue CM with compartments in series.

Definition in file sim3cms.c.

Function Documentation

simC3s()

int simC3s	(	double *	t,
		double *	ca,
		const int	nr,
		double	k1,
		double	k2,
		double	k3,
		double	k4,
		double	k5,
		double	k6,
		double *	ct,
		double *	cta,
		double *	ctb,
		double *	ctc )

Simulate tissue TAC using 1-3 tissue compartment model (compartments in series) and plasma TAC, at plasma TAC times.

Memory for ct must be allocated in the calling program. To retrieve the separate tissue compartment TACs, pointer to allocated memory for cta, ctb and/or ctc can be given; if compartmental TACs are not required, NULL pointer can be given instead.

The units of rate constants must be related to the time unit; 1/min and min, or 1/sec and sec.

Returns

Function returns 0 when successful, else a value >= 1.

Author

Vesa Oikonen

See also

simC3vs, simC1, simC3p, simC3vp, simC2l, simDispersion, simDelay

Parameters

t	Array of time values.
ca	Array of arterial activities.
nr	Number of values in TACs.
k1	Rate constant of the model.
k2	Rate constant of the model.
k3	Rate constant of the model.
k4	Rate constant of the model.
k5	Rate constant of the model.
k6	Rate constant of the model.
ct	Pointer for TAC array to be simulated; must be allocated.
cta	Pointer for 1st compartment TAC to be simulated, or NULL.
ctb	Pointer for 2nd compartment TAC to be simulated, or NULL.
ctc	Pointer for 3rd compartment TAC to be simulated, or NULL.

Definition at line 32 of file sim3cms.c.

  {
  int i;
  double b, c, d, w, z, dt2;
  double cai, ca_last, t_last;
  double ct1, ct1_last, ct2, ct2_last, ct3, ct3_last;
  double ct1i, ct1i_last, ct2i, ct2i_last, ct3i, ct3i_last;
 
 
  /* Check for data */
  if(nr<2) return 1;
  if(ct==NULL) return 2;
 
  /* Check actual parameter number */
  if(k1<0.0) return 3;
  if(k3<=0.0) {k3=0.0; if(k2<=0.0) k2=0.0;}
  else if(k5<=0.0) {k5=0.0; if(k4<=0.0) k4=0.0;}
  else {if(k6<=0.0) k6=0.0;}
 
  /* Calculate curves */
  t_last=0.0; if(t[0]<t_last) t_last=t[0]; 
  cai=ca_last=0.0;
  ct1_last=ct2_last=ct3_last=ct1i_last=ct2i_last=ct3i_last=0.0;
  ct1=ct2=ct3=ct1i=ct2i=ct3i=0.0;
  for(i=0; i<nr; i++) {
    /* delta time / 2 */
    dt2=0.5*(t[i]-t_last);
    /* calculate values */
    if(dt2<0.0) {
      return 5;
    } else if(dt2>0.0) {
      /* arterial integral */
      cai+=(ca[i]+ca_last)*dt2;
      /* partial results */
      b=ct1i_last+dt2*ct1_last;
      c=ct2i_last+dt2*ct2_last;
      d=ct3i_last+dt2*ct3_last;
      w=k4 + k5 - (k5*k6*dt2)/(1.0+k6*dt2);
      z=1.0+w*dt2;
      /* 1st tissue compartment and its integral */
      ct1 = (
          + k1*z*cai + (k3*k4*dt2 - (k2+k3)*z)*b
          + k4*c + k4*k6*dt2*d/(1.0+k6*dt2)
        ) / ( z*(1.0 + dt2*(k2+k3)) - k3*k4*dt2*dt2 );
      ct1i = ct1i_last + dt2*(ct1_last+ct1);
      /* 2nd tissue compartment and its integral */
      ct2 = (k3*ct1i - w*c + k6*d/(1.0+k6*dt2)) / z;
      ct2i = ct2i_last + dt2*(ct2_last+ct2);
      /* 3rd tissue compartment and its integral */
      ct3 = (k5*ct2i - k6*d) / (1.0 + k6*dt2);
      ct3i = ct3i_last + dt2*(ct3_last+ct3);
    }
    /* copy values to argument arrays */
    ct[i]=ct1+ct2+ct3;
    if(cta!=NULL) cta[i]=ct1;
    if(ctb!=NULL) ctb[i]=ct2;
    if(ctc!=NULL) ctc[i]=ct3;
    /* prepare to the next loop */
    t_last=t[i]; ca_last=ca[i];
    ct1_last=ct1; ct1i_last=ct1i;
    ct2_last=ct2; ct2i_last=ct2i;
    ct3_last=ct3; ct3i_last=ct3i;
  }
 
  return 0;
}

simC3vs()

int simC3vs	(	double *	t,
		double *	ca,
		double *	cb,
		const int	nr,
		const double	k1,
		const double	k2,
		const double	k3,
		const double	k4,
		const double	k5,
		const double	k6,
		const double	f,
		const double	vb,
		const double	fa,
		const int	vvm,
		double *	cpet,
		double *	cta,
		double *	ctb,
		double *	ctc,
		double *	ctab,
		double *	ctvb )

Simulate tissue TAC using 1-3 tissue compartment model (compartments in series) and plasma TAC, at plasma TAC times, considering also arterial and venous vasculature.

Memory for ct must be allocated in the calling program. To retrieve the separate tissue compartment TACs, pointer to allocated memory for cta, ctb, ctc, ctab, and/or ctvb can be given; if compartmental TACs are not required, NULL pointer can be given instead.

The units of rate constants must be related to the time unit; 1/min and min, or 1/sec and sec. If blood flow is set to 0, function assumes that f>>k1, and Cvb=Cab.,

Returns

Function returns 0 when successful, else a value >= 1.

Author

Vesa Oikonen

See also

simC3vp, simC3s, simC3p, simC2l, simC3vpKLoss, simC3DIvs, simC4DIvs, parExamplePerfectBolus

Parameters

t	Array of time values.
ca	Array of arterial plasma activities.
cb	Array of arterial blood activities.
nr	Number of values in TACs.
k1	Rate constant of the model.
k2	Rate constant of the model.
k3	Rate constant of the model.
k4	Rate constant of the model.
k5	Rate constant of the model.
k6	Rate constant of the model.
f	Blood flow; if 0, function assumes that f>>k1, and Cvb=Cab.
vb	Vascular volume fraction.
fa	Arterial fraction of vascular volume.
vvm	Vascular volume modelling: set to 0 to use Cpet = Vb*Cb + (1-Vb)*Ct, or set to 1 to use Cpet = Vb*Cb + Ct.
cpet	Pointer for TAC array to be simulated; must be allocated.
cta	Pointer for 1st compartment TAC to be simulated, or NULL.
ctb	Pointer for 2nd compartment TAC to be simulated, or NULL.
ctc	Pointer for 3rd compartment TAC to be simulated, or NULL.
ctab	Pointer for arterial TAC in tissue, or NULL.
ctvb	Pointer for venous TAC in tissue, or NULL.

Definition at line 143 of file sim3cms.c.

  {
  int i;
  double b, c, d, w, z, dt2, va, vv;
  double cai, ca_last, t_last, dct, cvb;
  double ct1, ct1_last, ct2, ct2_last, ct3, ct3_last;
  double ct1i, ct1i_last, ct2i, ct2i_last, ct3i, ct3i_last;
 
 
  /* Check for data */
  if(nr<2) return 1;
  if(cpet==NULL) return 2;
 
  /* Check parameters */
  if(k1<0.0) return 3;
  if(vb<0.0 || vb>=1.0) return 4;
  if(fa<=0.0 || fa>1.0) return 5;
  va=fa*vb; vv=(1.0-fa)*vb;
 
  /* Calculate curves */
  t_last=0.0; if(t[0]<t_last) t_last=t[0];
  cai=ca_last=0.0;
  ct1_last=ct2_last=ct3_last=ct1i_last=ct2i_last=ct3i_last=0.0;
  ct1=ct2=ct3=ct1i=ct2i=ct3i=0.0;
  for(i=0; i<nr; i++) {
    /* delta time / 2 */
    dt2=0.5*(t[i]-t_last);
    /* calculate values */
    if(dt2<0.0) {
      return 5;
    } else if(dt2>0.0) {
      /* arterial integral */
      cai+=(ca[i]+ca_last)*dt2;
      /* partial results */
      b=ct1i_last+dt2*ct1_last;
      c=ct2i_last+dt2*ct2_last;
      d=ct3i_last+dt2*ct3_last;
      w=k4 + k5 - (k5*k6*dt2)/(1.0+k6*dt2);
      z=1.0+w*dt2;
      /* 1st tissue compartment and its integral */
      ct1 = (
          + k1*z*cai + (k3*k4*dt2 - (k2+k3)*z)*b
          + k4*c + k4*k6*dt2*d/(1.0+k6*dt2)
        ) / ( z*(1.0 + dt2*(k2+k3)) - k3*k4*dt2*dt2 );
      ct1i = ct1i_last + dt2*(ct1_last+ct1);
      /* 2nd tissue compartment and its integral */
      ct2 = (k3*ct1i - w*c + k6*d/(1.0+k6*dt2)) / z;
      ct2i = ct2i_last + dt2*(ct2_last+ct2);
      /* 3rd tissue compartment and its integral */
      ct3 = (k5*ct2i - k6*d) / (1.0 + k6*dt2);
      ct3i = ct3i_last + dt2*(ct3_last+ct3);
    }
    /* Venous curve */
    if(f>0.) {dct = k1*ca[i] - k2*ct1; cvb = cb[i] - dct/f;} else cvb=cb[i];
    /* copy values to argument arrays */
    if(vvm==0) cpet[i]= va*cb[i] + vv*cvb + (1.0-vb)*(ct1+ct2+ct3);
    else cpet[i]= va*cb[i] + vv*cvb + (ct1+ct2+ct3);
    if(cta!=NULL) {cta[i]=ct1; if(vvm==0) cta[i]*=(1.0-vb);}
    if(ctb!=NULL) {ctb[i]=ct2; if(vvm==0) ctb[i]*=(1.0-vb);}
    if(ctc!=NULL) {ctc[i]=ct3; if(vvm==0) ctc[i]*=(1.0-vb);}
    if(ctab!=NULL) {ctab[i]=va*cb[i];}
    if(ctvb!=NULL) {ctvb[i]=vv*cvb;}
    /* prepare to the next loop */
    t_last=t[i]; ca_last=ca[i];
    ct1_last=ct1; ct1i_last=ct1i;
    ct2_last=ct2; ct2i_last=ct2i;
    ct3_last=ct3; ct3i_last=ct3i;
  }
 
  return 0;
}