Matlab - Matlab.In an assignment A(I) = B, the number of elements in B and I must be the same.

function [t,x,y,z] =Ejercicio_3_1(f,g,m,t0,T,x0,y0,z0,h)

      f=@(t,x,y,z)f;

      g=@(t,x,y,z)g;

      m=@(t,x,y,z)m;

      N=(T-t0)/h;

      t=t0:h:T;

      x=zeros(1,length(t));

      y=zeros(1,length(t));

      z=zeros(1,length(t));

      x(1)=x0; y(1)=y0;z(1)=z0;

        for i=1:(length(x)-1)

        k1=h*f(t(i),x(i),y(i),z(i));

        l1=h*g(t(i),x(i),y(i),z(i));

        r1=h*m(t(i),x(i),y(i),z(i));

        k2=h*f(t(i)+h/2,x(i)+k1/2,y(i)+l1/2,z(i)+r1/2);

        l2=h*g(t(i)+h/2,x(i)+k1/2,y(i)+l1/2,z(i)+r1/2);

        r2=h*m(t(i)+h/2,x(i)+k1/2,y(i)+l1/2,z(i)+r1/2);

        k3=h*f(t(i)+h/2,x(i)+k2/2,y(i)+l2/2,z(i)+r2/2);

        l3=h*g(t(i)+h/2,x(i)+k2/2,y(i)+l2/2,z(i)+r2/2);

        r3=h*m(t(i)+h/2,x(i)+k2/2,y(i)+l2/2,z(i)+r2/2);

        k4=h*f(t(i)+h,x(i)+k3,y(i)+l3,z(i)+r3);

        l4=h*g(t(i)+h,x(i)+k3,y(i)+l3,z(i)+r3);

        r4=h*m(t(i)+h,x(i)+k3,y(i)+l3,z(i)+r3);

        x(i+1)=x(i)+(k1+2*k2+2*k3+k4)/6;

        y(i+1)=y(i)+(l1+2*l2+2*l3+l4)/6;

        z(i+1)=z(i)+(r1+2*r2+2*r3+r4)/6;

>> [t,x,y,z] =runge_kutta

t =

         0    0.1000    0.2000    0.3000    0.4000    0.5000    0.6000    0.7000    0.8000    0.9000    1.0000

x =

    1.0000    1.0017    1.0057    1.0059    1.0005    0.9967    0.9834    0.9844    0.9846    0.9854    0.9863

y =

    2.0000    1.9646    1.8339    1.1891    1.6627    1.3403   -1.2200   -1.7983   -3.3401   -3.3708   -3.4110

z =

   -1.0000   -0.9877   -0.9420   -0.7133   -0.8812   -0.7622    0.1834    0.1212   -0.0120   -0.0117   -0.0114