MATLAB Object-Oriented Programming

Empty Arrays

In this section...

“Creating Empty Arrays” on page 10-8

“Assigning Values to an Empty Array” on page 10-8

Creating Empty Arrays

Empty arrays have no elements, but are of a certain class. All nonabstract classes have a

static method named empty that creates an empty array of the same class. The empty

method enables you to specify the dimensions of the output array. However, at least one

of the dimensions must be 0. For example, define the SimpleValue class:

classdef SimpleValue

properties

Value

end

methods

function obj = SimpleValue(v)

if nargin > 0

obj.Value = v;

end

end

end

end

Create a 5–by–0 empty array of class SimpleValue.

ary = SimpleValue.empty(5,0)

ary =

5x0 SimpleValue array with properties:

Value

Calling empty with no arguments returns a 0–by–0 empty array.

Assigning Values to an Empty Array

An empty object defines the class of an array. To assign nonempty objects to an empty

array, MATLAB calls the class constructor to create default instances of the class for

10 Object Arrays