MATLAB Function Reference |
Validate number of input arguments
Syntax
msgstring=
nargchk(minargs, maxargs, numargs) msgstring
=
nargchk(minargs, maxargs, numargs, 'string') msgstruct = nargchk(minargs, maxargs, numargs, 'struct')
Description
Use nargchk
inside an M-file function to check that the desired number of input arguments is specified in the call to that function.
msgstring
returns an error message string
=
nargchk(minargs, maxargs, numargs)
msgstring
if the number of inputs specified in the call numargs
is less than minargs
or greater than maxargs
. If numargs
is between minargs
and maxargs
(inclusive), nargchk
returns an empty matrix.
It is common to use the nargin
function to determine the number of input arguments specified in the call.
msgstring
is essentially the same as the command shown above, as
=
nargchk(minargs, maxargs, numargs, 'string')
nargchk
returns a string by default.
msgstruct
returns an error message structure
=
nargchk(minargs, maxargs, numargs, 'struct')
msgstruct
instead of a string. The fields of the return structure contain the error message string and a message identifier. If numargs
is between minargs
and maxargs
(inclusive), nargchk
returns an empty structure.
When too few inputs are supplied, the message string and identifier are
When too many inputs are supplied, the message string and identifier are
Remarks
nargchk
is often used together with the error
function. The error
function accepts either type of return value from nargchk
: a message string or message structure. For example, this command provides the error
function with a message string and identifier regarding which error was caught:
If nargchk
detects no error, it returns an empty string or structure. When nargchk
is used with the error
function, as shown here, this empty string or structure is passed as an input to error
. When error
receives an empty string or structure, it simply returns and no error is generated.
Examples
See Also
nargoutchk
, nargin
, nargout
, varargin
, varargout
, error
NaN | nargin, nargout |
© 1994-2005 The MathWorks, Inc.