FreeMat: STRUCT Structure Array Constructor

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STRUCT Structure Array Constructor

Section: Variables and Arrays

# Usage

Creates an array of structures from a set of field, value pairs. The syntax is

       y = struct(n_1,v_1,n_2,v_2,...)

where `n_i` are the names of the fields in the structure array, and `v_i` are the values. The values `v_i` must either all be scalars, or be cell-arrays of all the same dimensions. In the latter case, the output structure array will have dimensions dictated by this common size. Scalar entries for the `v_i` are replicated to fill out their dimensions. An error is raised if the inputs are not properly matched (i.e., are not pairs of field names and values), or if the size of any two non-scalar values cell-arrays are different.

Another use of the `struct` function is to convert a class into a structure. This allows you to access the members of the class, directly but removes the class information from the object.

# Example

This example creates a 3-element structure array with three fields, `foo` `bar` and `key`, where the contents of `foo` and `bar` are provided explicitly as cell arrays of the same size, and the contents of `bar` are replicated from a scalar.

    --> y = struct('foo',{1,3,4},'bar',{'cheese','cola','beer'},'key',508)

    y =
    1x3 struct array with fields:
        foo
        bar
        key
    --> y(1)

    ans =
        foo: 1
        bar: cheese
        key: 508
    --> y(2)

    ans =
        foo: 3
        bar: cola
        key: 508
    --> y(3)

    ans =
        foo: 4
        bar: beer
        key: 508

An alternate way to create a structure array is to initialize the last element of each field of the structure

    --> Test(2,3).Type = 'Beer';
    --> Test(2,3).Ounces = 12;
    --> Test(2,3).Container = 'Can';
    --> Test(2,3)

    ans =
        Type: Beer
        Ounces: 12
        Container: Can
    --> Test(1,1)

    ans =
        Type: 0
        Ounces: 0
        Container: 0