Error in Bvp4c

I'm trying to run the following bvp4c MATLAB code, but keep running into an error:

please anyone find out my mistakes and correct me..

Thank you.

Answer 1

[Jan]

You define the variable beta on top of the code, but this does not mean, that it is known in all subfunctions. Pr, gamma and lam are not known inside also.

Either define the constants, where they are needed, or provide them using an anonymous function:

for gamma=0.0:0.25:1
   sol  = bvpinit(linspace(0,5,50),[0 0 0 0 0 0 0]);
   fcn  = @(t,y) bvpexam1(t, y, beta, gamma, lam, Pr);
   sol1 = bvp4c(fcn, @bcexam1,sol);
   ...
end

function ysol = bvpexam1(t, y, beta, gamma, lam, Pr)
...
end

[Priya M]

sir, again occure same error..

[Jan]

Please post a current version of the code and a copy of the complete error message.

[Priya M]

fsol = bvp4c(f,res,solinit);

↑

Error: The expression to the left of the equals sign is not a valid target for an assignment.

[Jan]

f =@(x,y)[y(2);
  ...
  (1/(1+E*y(6)-Pr*gamma*y(1)^2))*(-E*y(7)^2-Pr*y(1)*y(7)+Pr*gamma*y(1)*y(2)*y(7))];
%                                                                                ^

There is a missing closing square bracket in your code. After adding it I get a result.

[Priya M]

Thanx a lot sir....

Answer 2

[MOSLI KARIM]

this code works function d

Pr=0.72;

beta=0.5;

lam=0.2;

E=0.5;

for gamma=0.0:0.25:1

sol = bvpinit(linspace(0,5,50),[0 0 0 0 0 0 0]);

sol1 = bvp4c(@bvpexam1, @bcexam1,sol);

x1 = sol1.x;

y1 = sol1.y;

figure (1)

plot(x1, y1(2,:));

hold on

figure (2)

plot(x1, y1(6,:));

hold on

z = y1(3,1);

p = y1(7,1)'

figure(3)

plot(gamma,y1(7,1),'-bo')

hold on

end

function res = bcexam1(y0, yinf)

res=[y0(1)-0;y0(2)-1;y0(4)-0;y0(6)-1;yinf(2)-0;yinf(4)-0;yinf(6)-0];

end

function ysol = bvpexam1(~,y)

yy1 = (1/(1-beta*y(1)^2))*(-y(1)*y(3)+y(2)^2-2*lam*(y(4)-beta*y(1)*y(5))-2*beta*y(1)*y(2)*y(3));

yy2 = (1/(1-beta*y(1)^2))*(-y(1)*y(5)+y(2)*y(4)+2*lam*(y(2)+beta*(y(2)^2-y(1)*y(3)+y(4)))-2*beta*y(1)*y(2)*y(5));

yy3 = (1/(1+E*y(6)-Pr*gamma*y(1)^2))*(-E*y(7)^2-Pr*y(1)*y(7)+Pr*gamma*y(1)*y(2)*y(7));

ysol = [y(2);y(3);yy1;y(5);yy2;y(7);yy3];

end