using matlabfunction to declare variables

I have three equations with names 'equn1, equn2, equn3'. Variables in those equations are declared as :

lam = sym('lam', [1 3] ).

To solve those equations, i am writing the code like this :

solu_fsolve = []; value = [];  lam(1)  = 0; lam(2) = 0; lam(3) = 0;
fh = matlabFunction([equn1;equn2;equn3],'vars',{[ lam(1), lam(2), lam(3)]});
options = optimset('Display','off','TolFun',eps);
[solu_fsolve,value] = fsolve(fh, [ 1,1,1] ,options ) ;

But, when i execute this code , i am getting an error like :

??? Error using ==> sym.matlabFunction>checkVars at 155
Variable names must be valid MATLAB variable names.  
Error in ==> sym.matlabFunction at 104
vars = checkVars(funvars,opts);

Can anyone please tell me how to declare the array as variables in matlabfunction?

Please help.

--kalpana

Answer 1

[Alan Weiss]

When you execute the first line of code you make lam a symbolic vector:

lam = sym('lam', [1 3] )

lam =

[ lam1, lam2, lam3]

However, you later change those variables to symbolic zeros instead of leaving them as variables.

lam(1)  = 0; lam(2) = 0; lam(3) = 0;

Remove that line of code and I expect that matlabFunction will work just fine.

Alan Weiss

MATLAB mathematical toolbox documentation