** Function M-files. **

** New functions may be added to MATLAB's vocabulary if they **

** are expressed in terms of other existing functions. The **

** commands and functions that comprise the new function must **

** be put in a file whose name defines the name of the new **

** function, with a filename extension of '.m'. At the top of **

** the file must be a line that contains the syntax definition **

** for the new function. For example, the existence of a file **

** on disk called STAT.M with: **

** **

** **

** function [mean,stdev] = stat(x) **

** n = length(x); **

** mean = sum(x) / n; **

** stdev = sqrt(sum((x - mean).^2)/n); **

** **

** **

** defines a new function called STAT that calculates the **

** mean and standard deviation of a vector. The variables **

** within the body of the function are all local variables. **

** See SCRIPT for procedures that work globally on the work- **

** space. **

** **

** **

** See also ECHO , SCRIPT . **

** **