Name
argn — number of arguments in a function call
Calling Sequence
[lhs [,rhs] ]=argn()
lhs=argn(1)
rhs=argn(2)
Description
This function is used inside a function definition.
It gives the number of actual inputs rhs
and output lhs
parameters passed to the function when the function is
called. It is usually used in function definitions to deal with
optional arguments.