Anonymous Functions in MATLAB
Niloufer Mackey
Example
>> g=@(x) [4*x(1)-x(2)*x(2);4*x(1)+x(2)]
g =
@(x)[4*x(1)-x(2)*x(2);4*x(1)+x(2)]
The @ character constructs the function handle, in this case g, to the anonymous function.
The @ character should be immediately followed by the list of input arguments to the function,
enclosed in round parentheses.
In this example, we have one input argument, the vector x.
Next, enter the expression that defines the function.
Thus, in this example, we have defined the vector valued function
([ ]) [
]
x1
4x1 − x22
g
=
x2
4x1 + x2
To evaluate g at the point (1, 1)
>>g([1 1])
ans =
3
5
Now here is an example of a function that takes an anonymous function as input.
function y = testhandle(f, x, h)
dx = h*ones(size(x));
y=(f(x) - f(x+dx))./h;
end
Here is call to testhandle
testhandle(g,[1 1], .1)
ans =
-1.9000
-5.0000
Created: 14 October 2011
Last Updated: Friday 14th October, 2011,
14:46