# [Scilab-users] 'ode' returns constant values for the variables

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## [Scilab-users] 'ode' returns constant values for the variables

 Hello, I try to solve the sisytema with the help of "ode". But I can not find where the error is; in the solution it returns constant values for the variables. I think the error is that I have not correctly declared the dependence of the variable variables "t". The expected solution should allow the graph to be reproduced: clear; funcprot(0); //Draghilev's Method timer(); function Sys=F(x)     Sys=[];     x0=x(1);x1=x(2);     Sys(1)=x1.^2+x0.^2 -8;     Sys(2)=sin(x0.*x1).*sin(exp(x0.*x1)); endfunction function Sys=F0(x)     Sys=[];     x00=x(1);x01=x(2);     Sys(1)=x01.^2+x00.^2-8;     Sys(2)=sin(x00.*x01).*sin(exp(x00.*x01)); endfunction function Sys=Mp(v)     [Sys]=F(v(1:2))-v(3)*F0(ics(1:2)); endfunction //deff('Sys=Mp(v)','[Sys]=F(v(1:2))-v(3).*F0(ics([1:2]))') function Sys=NF(v)     Sys=[];     [Sys]=numderivative(Mp,v); endfunction // //Z=NF // function  D=ODEs(ZZ) A=ZZ(:,1:2);b=ZZ(:,\$); A1=A;A1(:,1)=b; A2=A;A2(:,2)=b; D=-det(A); d(1)=det(A1) ; d(2)=det(A2); d(3)=D; [D]=-d; endfunction ics=[2;1]//[2.784;-0.5];[2;-0.5]; yint1=fsolve(ics,F) ics=[yint1]; disp(F(yint1),"x->f(x)=0",ics,"x f(x)=0") ics=[ics;1]; disp(ics) function [dxdt]=odes(t,x) [dxdt]=ODEs(NF(x)); endfunction N=200; smin=0.0; smax=15; h=0.000001; step=smax/N;     t=smin:step:smax;     t0=0;     atol=h;     LL= ode("fix",ics,t0,t,atol,odes) disp(timer(),"tiempo de ejecucion C"); clf(); subplot(1,2,1); a=get("current_axes")//get the handle of the newly created axes a.axes_visible="on"; // makes the axes visible a.font_size=3; //set the tics label font size a.x_location="middle"; //set the x axis position plot(t,LL(1,1:\$),"-cya",t,LL(2,1:\$),"-g",t,LL(3,1:\$),"-r") Gracias -- Sent from: http://mailinglists.scilab.org/Scilab-users-Mailing-Lists-Archives-f2602246.html_______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users