how do i correct this error in command bvp4c?

the optimal control i used the command BVP4C but i don't use because generates me a this error

my code is:

function dydx = ex1ode(x,y)

   dydx = [y(2)
       -2.2727*y(1)+ (-1.1364)*y(2)+(0.0136)*y(3)
       (-11)*y(2)+(-40)*y(3)+(1000)*((-1000*y(6))/2*1)
       (-2.2727)*y(5),y(4)+((-1.1364)*y(5))+(-11*y(6))
       (-1.1364*y(5))+(-40*y(6))];

the other function is

function res = ex1bc(ya,yb)
res = [ ya(1); yb(1)-1

          ya(2); yb(2)-10

          ya(3); yb(3)-1 

          ya(4); yb(4)-1

          ya(5); yb(5)-1

          ya(6); yb(6)-1];

and the principal program is,

clear all 

clc

solinit = bvpinit(linspace(0,18,6),[0 0 0 0 0 1])

sol = bvp4c(@ex1ode,@ex1bc,solinit);

x = linspace(0,4);

y = deval(sol,x);

plot(x,y(1,:))

I don't know which the problem

Error using vertcat
Dimensions of matrices being concatenated are not consistent.
Error in ex1ode (line 3)
 dydx = [y(2)

Error in bvparguments (line 105)
    testODE = ode(x1,y1,odeExtras{:});

Error in bvp4c (line 130)
    bvparguments(solver_name,ode,bc,solinit,options,varargin);

thanks.

Answer 1

[Walter Roberson]

You have

   dydx = [y(2)
       -2.2727*y(1)+ (-1.1364)*y(2)+(0.0136)*y(3)
       (-11)*y(2)+(-40)*y(3)+(1000)*((-1000*y(6))/2*1)
       (-2.2727)*y(5),y(4)+((-1.1364)*y(5))+(-11*y(6))
       (-1.1364*y(5))+(-40*y(6))];

Notice that in the fourth line you have

         (-2.2727)*y(5),y(4)+((-1.1364)*y(5))+(-11*y(6))

that is a comma between the y(5) and y(4), and it indicates that you are putting a second value horizontally at that location, making two entries on that row but all the other rows have only one entry.

You probably need

   dydx = [y(2)
       -2.2727*y(1)+ (-1.1364)*y(2)+(0.0136)*y(3)
       (-11)*y(2)+(-40)*y(3)+(1000)*((-1000*y(6))/2*1)
       (-2.2727)*y(5)
       y(4)+((-1.1364)*y(5))+(-11*y(6))
       (-1.1364*y(5))+(-40*y(6))];

Answer 2

[Stefany Rodriguez]

yes, I have a mistake but i don't know

Error using bvparguments (line 111)
Error in calling BVP4C(ODEFUN,BCFUN,SOLINIT):
  The boundary condition function BCFUN should return a column vector of length 6.

Error in bvp4c (line 130)

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

Error in controloptimo (line 4)

sol = bvp4c(@ex1ode,@ex1bc,solinit);

and my principal code is

clear all 

clc

solinit = bvpinit(linspace(0,18,6),[0 0 0 0 0 1])

sol = bvp4c(@ex1ode,@ex1bc,solinit);

x = linspace(0,4);

y = deval(sol,x);

plot(x,y(1,:))

and my functions are equals, his answer I solve my problem but now I have a new problem.

[Walter Roberson]

The code

function res = ex1bc(ya,yb)
res = [ ya(1); yb(1)-1
          ya(2); yb(2)-10
          ya(3); yb(3)-1 
          ya(4); yb(4)-1
          ya(5); yb(5)-1
          ya(6); yb(6)-1];

returns a column vector of length 12, but it needs to return a column of length 6.

The length of the column vectors returned by ex1ode and ex1bc need to be the same as the length of the initial condition [0 0 0 0 0 1]

[Stefany Rodriguez]

thanks, his answer is correct ;D