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MATLAB Programming/Advanced Topics/Numerical Manipulation/More complicated matrix operations
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Row reduced echelon form
To find the Row reduced echelon form of a matrix just use the MATLAB command rref
Example:
a=[1 2 3; 4 5 6];
b=rref(a);
It's that simple. (I believe that MATLAB uses the Gauss-Jordan elimination method to make this computation; don't quote me on that (I'm not even sure if there are other methods)).
Inverse
To find the inverse of a matrix use the MATLAB command inv.
(note that the matrix must be square)
Example:
a=[1 2 3;4 5 6;7 8 9];
b=inv(a);
Cofactor, minor
The Jacobian
t=jacobian(e,w);
e is a scalar vector, w is a vector of functions. Also, this does not solve equations symbolically unless you define the w vector functions as symbolics prior to executing this statement.
Example:
syms x y z;
w=[x y z];
e=[1 2 3];
t=jacobian(e,w);