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A structure array is a particular instance of a structure, where each of the fields of the structure is represented by a cell array. Each of these cell arrays has the same dimensions. Conceptually, a structure array can also be seen as an array of structures with identical fields. An example of the creation of a structure array is
x(1).a = "string1"; x(2).a = "string2"; x(1).b = 1; x(2).b = 2;
which creates a 2-by-1 structure array with two fields.  Another way
to create a structure array is with the struct function
(see Creating Structures).  As previously, to print the value of
the structure array, you can type its name:
x
     ⇒ x =
        {
          1x2 struct array containing the fields:
            a
            b
        }
Individual elements of the structure array can be returned by indexing
the variable like x(1), which returns a structure with
two fields:
x(1)
     ⇒ ans =
        {
          a = string1
          b =  1
        }
Furthermore, the structure array can return a comma separated list of field values (see Comma Separated Lists), if indexed by one of its own field names. For example:
x.a
     ⇒
        ans = string1
        ans = string2
Here is another example, using this comma separated list on the left-hand side of an assignment:
[x.a] = deal ("new string1", "new string2");
 x(1).a
     ⇒ ans = new string1
 x(2).a
     ⇒ ans = new string2
Just as for numerical arrays, it is possible to use vectors as indices (see Index Expressions):
x(3:4) = x(1:2);
[x([1,3]).a] = deal ("other string1", "other string2");
x.a
     ⇒
        ans = other string1
        ans = new string2
        ans = other string2
        ans = new string2
The function size will return the size of the structure.  For
the example above
size (x)
     ⇒ ans =
          1   4
Elements can be deleted from a structure array in a similar manner to a numerical array, by assigning the elements to an empty matrix. For example
in = struct ("call1", {x, Inf, "last"},
             "call2", {x, Inf, "first"})
     ⇒ in =
        {
          1x3 struct array containing the fields:
            call1
            call2
        }
in(1) = [];
in.call1
     ⇒
       ans = Inf
       ans = last
Next: Creating Structures, Previous: Basic Usage and Examples, Up: Structures [Contents][Index]