Broydens Method

Compute the solution for a system of nonlinear equations.

Description

An example of the use of Broyden's method.

This file does not require the use of another, and the equations to be solved can be passed into the function. Only (2x2).

However if you wish to change this method for more equations feel free to make the required adjustments.

Example: x = broyden('x1+2*x2-2','x1^2+4*x2^2-4',[1 1]',50)

will give output

x =
   -0.0000
    1.0000

• MATLAB release: MATLAB 7 (R14)

[Henk den Adel]

s = B\(-f);

f, the Jacobian matrix, should not be singular. Suggestion for inprovement:
if det(f) > 1E-19
   s = B\(-f);
else
   MessageBox('Jacobian is singular');
   return;
end

[Duane Hanselman]

Solves only two equations in two unknowns and appears to require the Symbolic Toolbox. Calls the Function EVAL.

Very poor programming practices used.

Hen den Adel's suggesting of using det(f) is equally poor programming practice. The closeness of the determinant to zero does not measure how close to singular matrix is.