6.1.4 Manipulating Structures

Other functions that can manipulate the fields of a structure are given below.

Built-in Function: rmfield (s, f)

Remove field f from the structure s. If f is a cell array of character strings or a character array, remove the named fields.

See also: cellstr, iscellstr, setfield.

Function File: [k1, …, v1] = setfield (s, k1, v1, …)

Set field members in a structure.

oo(1,1).f0 = 1; oo = setfield (oo, {1,2}, "fd", {3}, "b", 6); oo(1,2).fd(3).b == 6 ⇒ ans = 1

Note that this function could be written

i1 = {1,2}; i2 = "fd"; i3 = {3}; i4 = "b"; oo(i1{:}).(i2)(i3{:}).(i4) == 6;

See also: getfield, rmfield, isfield, isstruct, fieldnames, struct.

Function File: [t, p] = orderfields (s1, s2)

Return a struct with fields arranged alphabetically or as specified by s2 and a corresponding permutation vector.

Given one struct, arrange field names in s1 alphabetically.

Given two structs, arrange field names in s1 as they appear in s2. The second argument may also specify the order in a permutation vector or a cell array of strings.

See also: getfield, rmfield, isfield, isstruct, fieldnames, struct.

Built-in Function: fieldnames (struct)

Return a cell array of strings naming the elements of the structure struct. It is an error to call fieldnames with an argument that is not a structure.

Built-in Function: isfield (expr, name)

Return true 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.

Function File: [v1, …] = getfield (s, key, …)

Extract fields from a structure. For example

ss(1,2).fd(3).b = 5; getfield (ss, {1,2}, "fd", {3}, "b") ⇒ ans = 5

Note that the function call in the previous example is equivalent to the expression

i1 = {1,2}; i2 = "fd"; i3 = {3}; i4= "b"; ss(i1{:}).(i2)(i3{:}).(i4)

See also: setfield, rmfield, isfield, isstruct, fieldnames, struct.

Function File: substruct (type, subs, …)

Create a subscript structure for use with subsref or subsasgn.

See also: subsref, subsasgn.