Should I handle unexpected arguments of a function?

How should I approach writing a MATLAB function evaluating a conditional logarithmic function with a variable number of arguments?

• Write a Matlab function call_functions to evaluate the function      f(x,y)=ln(1/1-x)*ln(1/1-y).       Note that call_function will have two input arguments x and y and this function will call f_x [which equals ln(1/1-x)] function twice to evaluate f(x,y).   From the command window test your program for x=0.5, y=0.5 and x=1, y=0.5. For #3 use the script for number 2.   function if [f_xy]=-999999; else [f_xy]=log((1-x)^(-1))*log((1-y)^(-1)); end         If anyone could help understand how to approach this it would really help!   Thanks.   And would I am vague on commands such as feval, eval, and nargin. And vague on applying subfunctions and nested functions.   Any approach would help. Please explain in laymens terms.

• Answer:

  First, learn to use .* ./ .^ There is nothing telling you that your input will be scalars and not vectors or matrices. This  assignment calls for using subfunctions. At the end of your function you should add function f=f_x(z) f=log(1./(1-z)); end Then you should call it in your formula like this: f_xy=f_x(x).*f_x(y); ...