str2func (MATLAB Functions)

MATLAB Function Reference

str2func

Construct function handle from function name string

Syntax

```
fhandle = str2func('str')
```

Description

str2func('str') constructs a function handle fhandle for the function named in the string 'str'.

You can create a function handle using either the @function syntax or the str2func command. You can also perform this operation on a cell array of strings. In this case, an array of function handles is returned.

Examples

Example 1

To convert the string, 'sin', into a handle for that function, type

```
fh = str2func('sin')
fh = 
    @sin
```

Example 2

If you pass a function name string in a variable, the function that receives the variable can convert the function name to a function handle using str2func. The example below passes the variable, funcname, to function makeHandle, which then creates a function handle. Here is the function M-file:

function fh = makeHandle(funcname)
fh = str2func(funcname);

This is the code that calls makdHandle to construct the function handle:

```
makeHandle('sin')
ans = 
    @sin
```

Example 3

In the following example, the myminbnd function expects to receive either a function handle or string in the first argument. If you pass a string, myminbnd constructs a function handle from it using str2func, and then uses that handle in a call to fminbnd:

function myminbnd(fhandle, lower, upper)
if ischar(fhandle)
    disp 'converting function string to function handle ...'
    fhandle = str2func(fhandle);
end
fminbnd(fhandle, lower, upper)

Whether you call myminbnd with a function handle or function name string, the function can handle the argument appropriately:

myminbnd('humps', 0.3, 1)
converting function string to function handle ...
ans =
    0.6370

str2double str2mat