Structures may be copied. Since structures are themselves values, structure elements may reference other structures. The following statements change the value of the element b of the structure x to be a data structure containing the single element d , which has a value of 3. This prevents long and confusing output from large deeply nested structures. The default value is 2.
Functions can return structures.
For example, the following function separates the real and complex parts of a matrix and stores them in two elements of the same structure variable. The following functions are available to give you information about structures. Return 1 if the expression expr is a structure and it includes an element named name . The first argument must be a structure and the second must be a string. Return a list of strings naming the elements of the structure struct .