What's the context in which you see that term? There are at least three different meanings for that term, though two of them are somewhat related.
- Handle as related to graphics? Start with this documentation page. Graphics handles let you manipulate graphics objects on screen; for example if I have a line's handle I can change its Color property and so change what color it is.
h = plot(1:10, 1:10); % h is the line's handle. By default it is blue.
figure % Let's make a second line so you can see the difference when I change its color
h2 = plot(1:10, 1:10);
h2.Color = 'r'; % Let's make this line red
- Handle in terms of object-oriented programming? See here, though this is often thought of as an advanced skill for MATLAB programming. Graphics handles are handle objects, though not all handle objects are graphics objects.
- Handle as related to evaluating a function, like with an ODE solver or optimization routine? Those are function handles, which are useful in passing a "reference" to function A into function B so that function B can call function A with input arguments of its choice.
f = @sin;
Find a zero of the function y = sin(x). Start looking at 1. fzero will call f with points of its choosing as it looks for a solution.
x = fzero(f, 1)
To check, evaluate the function handle yourself at the point fzero found.
shouldBeCloseTo0 = f(x)
That's pretty close to 0.
