How to write a Matlab-function which returns a reduced row form of matrix

I have the following matrix M = [ 0 0 1 2; 1 2 1 0; 2 4 3 2; 1 2 2 2 ] and the function needs to reduce rows, but it is not the same as rref fuction.

[madhan ravi]

why its not rref()?

Answer 1

[Jack Gallahan]

Could this post be of use? It shows how to find the reduced form a matrix without using rref.