Programming |
Finding the Size of Structure Arrays
Use the size
function to obtain the size of a structure array, or of any structure field. Given a structure array name as an argument, size
returns a vector of array dimensions. Given an argument in the form array(n).field
, the size
function returns a vector containing the size of the field contents.
For example, for the 1-by-3 structure array patient
, size(patient)
returns the vector [1 3]
. The statement size(patient(1,2).name)
returns the length of the name
string for element (1,2)
of patient
.
Adding Fields to Structures
You can add a field to every structure in an array by adding the field to a single structure. For example, to add a social security number field to the patient
array, use an assignment like
Now patient(2).ssn
has the assigned value. Every other structure in the array also has the ssn
field, but these fields contain the empty matrix until you explicitly assign a value to them.
To add new fields to a structure, specifying the names for these fields at run-time, see the section on Using Dynamic Field Names.
Deleting Fields from Structures
You can remove a given field from every structure within a structure array using the rmfield
function. Its most basic form is
where array
is a structure array and 'field'
is the name of a field to remove from it. To remove the name
field from the patient
array, for example, enter
Using Dynamic Field Names | Applying Functions and Operators |
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