For the case of being called with no parmeters or too few parameters, you can use nargin() to test how many parameters were provided, and can do whatever is appropriate for the situation.
For the case of being called with too many parameters, then nargin() alone cannot solve the problem: MATLAB would normally detect the problem before entering the function at all. However, if you specify the last parameter name as the magic name varargin then MATLAB will permit any number of parameters, and you can then test nargin() to determine if too many parameters were passed. For example,
function feet2metersV2(altitudeValue, varargin)
if nargin < 1
%no parameters case
elseif nargin > 1
%too many parameters case
else
%right number of parameters case
end
end
