`structfun`

Applies a function to each field of a scalar struct.

Category: Language Fundamentals > Data Types

Syntax

A = structfun(func, S)

Calls func on every field value and collects the results in a column vector.

B = structfun(func, S, 'UniformOutput', false)

Returns a struct with the same field names holding the results.

Description

structfun is the struct counterpart of cellfun and arrayfun. It is helpful for summaries over a set of named values, such as structfun(@numel, s) for the size of each field.

When the function returns non-scalar results (strings, vectors), set 'UniformOutput' to false; otherwise an error is raised.

Input arguments

func: Function handle that takes one field value.
S: Scalar struct.
'UniformOutput': true (default) requires every result to be a scalar; false allows any result and returns a struct.

Output arguments

A: Column vector with one element per field, in field order.

Example

Column result and struct result

s.a = 1; s.b = 4; s.c = 9;
structfun(@sqrt, s)
r = structfun(@(v) v*2, s, 'UniformOutput', false)

Output

ans = 3×1

     1
     2
     3
r = struct with fields:

    a: 2
    b: 8
    c: 18

structfun