Figure Properties - SERC

fminbnd
2-860
The argument fun can also be a function handle for an anonymous function.
For example, to find the minimum of the function fx ( ) x on the
interval (0,2), create an anonymous function f
3 =
– 2x – 5
f = @(x)x.^3-2*x-5;
Then invoke fminbnd with
x = fminbnd(f, 0, 2)
The result is
x =
0.8165
The value of the function at the minimum is
y = f(x)
y =
-6.0887
If fun is parameterized, you can use anonymous functions to capture the
problem-dependent parameters. For example, suppose you want to minimize
the objective function myfun defined by the following M-file function.
function f = myfun(x,a)
f = (x - a)^2;
Note that myfun has an extra parameter a, so you cannot pass it directly to
fminbind. To optimize for a specific value of a, such as a = 1.5.
1 Assign the value to a.
a = 1.5; % define parameter first
2 Call fminbnd with a one-argument anonymous function that captures that
value of a and calls myfun with two arguments:
x = fminbnd(@(x) myfun(x,a),0,1)
Algorithm The algorithm is based on golden section search and parabolic interpolation. A
Fortran program implementing the same algorithm is given in [1].