Matlab Functions - struct

struct

The struct function constructs a structure (or structure array) from field/value pairs. It is an alternative to building a structure incrementally with dot assignment, useful when the fields are known up front or when a structure array of identical schema is needed.

• s = struct returns a 1×1 structure with no fields
• s = struct(field,value) creates a single-field structure
• s = struct(field1,value1,...,fieldN,valueN) creates a structure with multiple fields in one call
• s = struct([]) returns a 0×0 empty structure with no fields

Field Names

• field is a char vector or string scalar that obeys the rules of variable names
• Duplicate field names raise an error

Structure Arrays from Cell Arrays

When value is a cell array, struct does not put the cell into a single field. Instead, it spreads the cells across a structure array: each cell becomes the field value of one element, and the array’s size matches the cell’s size.

• To store a cell array as a single field value, wrap it in another cell: struct('f',{{1,2,3}}) produces a scalar struct whose field f is the inner 1×3 cell.

>> s = struct('name',{'Alice','Bob'},'age',{30,42})
s =
  1x2 struct array with fields:
    name
    age
>> s(2)
ans =
  struct with fields:
    name: 'Bob'
     age: 42

When several values are cell arrays, they must all have the same size; that size becomes the size of the resulting structure array.