MATLAB: Loop for bvp4c function with an unknown parameter

Question

I tried to solve sixth order differential equation using bvp4c with an unknown parameter “S” and one variable parameter “k”. I have written a subroutine as a bvp4c and a main function for “k”.

The main code is written as follows:

function [] = main()

kk=0.5 ;

for i=1:60

    k=kk;
     valuePresentstudy = Surfactant(k); 
             kk=kk+0.1;
    end
 end

The bvp4c subroutine is written as follows:

function valuePresentstudy = Surfactant(k)

options = bvpset('NMax',100000);

S=0.28;

solinit = bvpinit(linspace(0,1,100),[0.1 0 0 0 0 0],S);

sol = bvp4c(@(x,y)fourode(x,y,k),@(ya,yb)fourbc(ya,yb,k),solinit,options);

save hatimsol.mat sol

x = linspace(0,1);

y = deval(sol,x);

valuePresentstudy=y;

%

function dydx = fourode(x,y,S,k)

Pr=10;

dydx = [ y(2); y(3); y(4); -(k^4+(S/Pr)*k^2)*y(1)+(2*(k^2)+(S/Pr))*y(3); y(6); (k^2+S)*y(5)-y(1)];

%

function res = fourbc(ya,yb,S,k)

e=0;

res = [ ya(1); ya(2); ya(5); yb(1); yb(6)+e*k*yb(5); yb(5)-1; yb(6)];

The error is given as:

Error using Surfactant>@(x,y)fourode(x,y,k)

Too many input arguments.

Error in bvparguments (line 105)

    testODE = ode(x1,y1,odeExtras{:});

Error in bvp4c (line 130)

    bvparguments(solver_name,ode,bc,solinit,options,varargin);

Error in Surfactant (line 5)

sol = bvp4c(@(x,y)fourode(x,y,k),@(ya,yb)fourbc(ya,yb,k),solinit,options);

Error in MainPresentSurfactant (line 6)

     valuePresentstudy = Surfactant(k);

Could you please tell me where my mistake is?

Thanks in advance for your help.

Answer 1

Maybe

sol = bvp4c(@(x,y,S)fourode(x,y,S,k),@(ya,yb,S)fourbc(ya,yb,S,k),solinit,options);

Otherwise pass k to fourode and fourbc as global.

Best wishes

Torsten.