write(%io(2),'reactions trimoleculaire ([Mur], page 156)');
a=evstr(x_dialog('valeur de a','0.2'));
b=evstr(x_dialog('valeur de b','0.5'));
cc=ones(2,1);
c0=evstr(x_matrix('concentrations initiales',cc));
tpas=evstr(x_dialog('pas de temps','0.05'));
tfin=evstr(x_dialog('temps final','50'));
getf('C:\Mes Documents\Agreg\oraux\equadiff\reac6.sci');
npts=int(tfin/tpas);
t=0:tpas:tfin;xdim=[0,0,2*c0(1),2*c0(2)];
//
// solution ode
X=ode(c0,0,t,list(reac6,a,b));
//
xbasc()
xsetech([0,0,0.5,0.5]);
   plot2d(t,X(1,:));
   xtitle('concentration de X','t')
xsetech([0.5,0,0.5,0.5]);
   plot2d(t,X(2,:));
   xtitle('concentration de Y','t')
xsetech([0,0.5,1,0.5]);
plot2d(X(1,:),X(2,:),1,'011',' ',xdim);
xtitle('portrait de phase')
pause;
portrait(list(reac6,a,b),'default',xdim,[npts;tpas])
//