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Vectors as arrays & advanced data structures
id: ’MNGTHA003’ marks: [36 49 74] Here’s how to access her second mark: student.marks(2) ans = 49 Note the use of the dot to separate the structure name from its fields when creating it and when accessing its fields. To add further elements to the structure, use subscripts after the structure name: student(2).name = ’Charles Wilson’ student(2).id = ’WLSCHA007’ student(2).marks = [49 98] (the original student, Thandi Mangwane, is now accessed as student(1)). Note that field sizes do not have to conform across elements of a structure array: student(1).marks has three elements, while student(2).marks has only two elements. The student structure now has size 1-by-2: it has two elements, each element being a student with three fields. Once a structure has more than one element MATLAB does not display the contents of each field when you type the structure name at the command line. Instead, it gives the following summary: student student = 1x2 struct array with fields: name id marks You can also use fieldnames(student) to get this information. A structure array can be pre-allocated with the struct function. See Help. A structure field can contain any kind of data, even another structure—why ever not? Thus we can create a structure course of courses taken by students,
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