write(%io(2),'reactions enzymatiques ([Bil], page 39)');
c0=evstr(x_dialog('valeur initiale de C','0'));
s0=evstr(x_dialog('valeur initiale de S','1'));
e0=evstr(x_dialog('valeur initiale de E','1'));
k=evstr(x_dialog('taux de reaction 1 directe','100'));
r=evstr(x_dialog('taux de reaction 1 inverse','90'));
d=evstr(x_dialog('taux de reaction 2 directe','1'));
tpas=evstr(x_dialog('pas de temps de calcul','0.02'));
X0=[c0;s0];X=[];
getf('C:\Mes Documents\Agreg\oraux\equadiff\reac4.sci');
tfin=12;
t=0:tpas:tfin;
//
// solution ode
X=ode(X0,0,t,list(reac4,e0,s0,c0,k,r,d));
//
xbasc()
xsetech([0,0,0.5,0.5]);
plot2d(t,X(1,:),1,'121','C solveur Scilab');
xtitle('concentration de C','t')
xsetech([0.5,0,0.5,0.5]);
plot2d(t,X(2,:),1,'121','S solveur Scilab');
xtitle('concentration de S','t')
xsetech([0,0.5,0.5,0.5]);
plot2d(X(1,:),X(2,:),1,'011',' ',[0,0,1.5,1.5]);
xtitle('portrait de phase','C','S')
xsetech([0.5,0.5,0.5,0.5]);
plot2d([t',t',t'],[k*X(1,:)',r*X(1,:)',d*X(1,:)'],[1,2,3]);
xtitle('vitesses comparee des trois reactions','t')
//