feval - Evaluate function

Syntax

Description

[y1, y2, ...] = feval(fhandle, x1, ..., xn) evaluates the function handle, fhandle, using arguments x1 through xn. If the function handle is bound to more than one built-in or .m function, (that is, it represents a set of overloaded functions), then the data type of the arguments x1 through xn determines which function is dispatched to.

Note   It is not necessary to use feval to call a function by means of a function handle. This is explained in Calling a Function By Means of Its Handle in the MATLAB Programming Fundamentals documentation.

[y1, y2, ...] = feval(fname, x1, ..., xn). If fname is a quoted string containing the name of a function (usually defined within file having a .m file extension), then feval(fname, x1, ..., xn) evaluates that function at the given arguments. The fname parameter must be a simple function name; it cannot contain path information.

Tips

The following two statements are equivalent.

[V,D] = eig(A)
[V,D] = feval(@eig, A)

Nested functions are not accessible to feval. To call a nested function, you must either call it directly by name, or construct a function handle for it using the @ operator.

Examples

The following example passes a function handle, fhandle, in a call to fminbnd. The fhandle argument is a handle to the humps function.

fhandle = @humps;
x = fminbnd(fhandle, 0.3, 1);

The fminbnd function uses feval to evaluate the function handle that was passed in.

function [xf, fval, exitflag, output] = ...
    fminbnd(funfcn, ax, bx, options, varargin)
            .
            .
            .
fx = feval(funfcn, x, varargin{:});

See Also

assignin | builtin | eval | evalin | function_handle | functions

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