WRITE "pharmacokinetics"$

% B_ IS THE VARIABLE VECTOR 
B_:={x1,x2,x3,x4,y1,y2}$

FOR EACH EL_ IN B_ DO DEPEND EL_,T$

%B1_ IS THE UNKNOWN PARAMETER VECTOR
B1_:={a1,a2,b1,b2,ka,kc,vm}$

%NUMBER OF STATES 
NX_:=4$
%NUMBER OF INPUTS 
NU_:=0$
%NUMBER OF OUTPUTS 
NY_:=2$

%MODEL EQUATIONS
C_:={df(x1,t)=a1*(x2-x1)-ka*vm*x1/(kc*ka+kc*x3+ka*x1),
     df(x2,t)=a2*(x1-x2),
     df(x3,t)=b1*(x4-x3)-kc*vm*x3/(kc*ka+kc*x3+ka*x1),
     df(x4,t)=b2*(x3-x4),
     y1=x1,
     y2=x4}$

SEED_:=25$
DAISY()$

% INITIAL CONDITIONS
%IC_:={x1=c0,x2=0,x3=g*c0,x4=0}$
%CONDINIZ()$
END$

