Numeric solution of differential equation system

Sasha Rats

2017 9 4

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I need to solve system which has the form:

A*diff (chi1(r), r, 2) + B*chi1(r)+ D*chi2(r) = Q(r)

E*diff (chi2(r), r, 2) + F*chi2(r)+ G*chi1(r) = 0

with boundary conditions: chi1(0) = 0, chi1(1000) = 0, chi2(0) = 0, chi2(1000) = 0

I wrote next code, but nothing works. Help me please!

 function soleq
global sol
clc
solinit = bvpinit(linspace(0,12),[0 1000]);
sol = bvp4c(@ode4,@bc2,solinit);
plot(sol.x, sol.y), grid on
legend('y(t)','dy(t)')
xlabel('t') 
end
function du = ode4(t,u)
mp = 938.2720813; mn = 939.5654133; hbar = 197.3270533;
V0 = 20; EIm = 0.3; mu = (mn+mp)*(1/4); Q0 = 1.5; Rq = 4.5; Rv = 1.5;  ERe =1;
du = [((-2*mu*t*Q0*exp(-t/Rq)+2*mu*(-V0*exp(-t/Rv)-ERe)*u(3)+2*mu*EIm*u(4))/hbar^2); -(2*mu/hbar^2)*((ERe+V0*exp(-t/Rv))*u(4)+EIm*u(3));
 u(1); u(2)];
end
 function res=bc2(ua,ub) 
res = [ ua(3) ; ub(3) ;
ua(4) ; ub(4) ];
 end