Glossary - A Guide to MATLAB for Beginners and Experienced Users - page 315

isempty True if an array is empty.
isfinite Checks whether elements of an array are finite.
isfinite(1./[-1 0 1])

ishold True if hold on is in effect.
isinf Checks whether elements of an array are infinite.
isletter Checks whether elements of a string are letters of the alphabet.
str = 'remove my spaces'; str(isletter(str))

isnan Checks whether elements of an array are “not-a-number” (which results from
indeterminate forms suchas 0 / 0).

isnan([-1 0 1]/0)
isnumeric True if an object is of a numeric class.
ispc True if MATLAB is running on a Windows computer.
isreal True if an array consists only of real numbers.
isspace Checks whether elements of a string are spaces, tabs, etc.
isunix True if MATLAB is running on a UNIX computer.
keyboard Returns control from an M-file to the keyboard. Useful for debugging
M-files.

mex Compiles a MEX program.
nargin Returns the number of input arguments passed to a function M-file.
if (nargin < 2); error('Wrong number of arguments'); end
nargout Returns the number of output arguments requested from a function M-file.
otherwise Used to delimit an alternative case after a switch statement.
pause Suspends execution of an M-file until the user presses a key.
return Terminates execution of an M-file early or returns to an M-file after a
keyboard command.
if abs(err) < tol; return; end

switch Alternative to if that allows branching to more than two cases. Must be
terminated by end .
switch num
case 1
disp('Yes.')
case 0