Simple MATLAB question

Here is the .m file
but how can I run it on matlab ??????

Notes:
function [k,p,err,P] = fixpt(g,p0,tol,max1)

% Input - g is the iteration function
% - p0 is the initial guess for the fixed-point
% - tol is the tolerance
% - max1 is the maximum number of iterations
% Output - k is the number of iterations that were carried out
% - p is the approximation to the fixed-point
% - err is the error in the approximation
% - P'contains the sequence {pn}

http://www.math.duke.edu/education/c.../mlabtut9.html

explains how matlab module files can be used.

enough tutorials

I don't know how to write the command
>> ??????????

how to return variables or how to input them