getfield (MATLAB Functions)

Get field of structure array

Note getfield is obsolete and will be removed in a future release. Please use dynamic field names instead.

Syntax

f = getfield(s,'field')
f = getfield(s,{i,j},'field',{k})

Description

f = getfield(s,'field'), where s is a 1-by-1 structure, returns the contents of the specified field. This is equivalent to the syntax f = s.field.

If s is a structure having dimensions greater than 1-by-1, getfield returns the first of all output values requested in the call. That is, for structure array s(m,n), getfield returns f = s(1,1).field.

f = getfield(s,{i,j},'field',{k}) returns the contents of the specified field. This is equivalent to the syntax f = s(i,j).field(k). All subscripts must be passed as cell arrays--that is, they must be enclosed in curly braces (similar to{i,j} and {k} above). Pass field references as strings.

Examples

Given the structure

mystr(1,1).name = 'alice';
mystr(1,1).ID = 0;
mystr(2,1).name = 'gertrude';
mystr(2,1).ID = 1

Then the command f = getfield(mystr,{2,1},'name') yields

```
f =

gertrude
```

To list the contents of all name (or other) fields, embed getfield in a loop.

for k = 1:2
    name{k} = getfield(mystr,{k,1},'name');
end
name

name = 

    'alice'    'gertrude'

The following example starts out by creating a structure using the standard structure syntax. It then reads the fields of the structure using getfield with variable and quoted field names and additional subscripting arguments.

class = 5;     student = 'John_Doe';
grades(class).John_Doe.Math(10,21:30) = ...
             [85, 89, 76, 93, 85, 91, 68, 84, 95, 73];

Use getfield to access the structure fields.

getfield(grades,{class}, student, 'Math', {10,21:30})

ans =

    85    89    76    93    85    91    68    84    95    73

getenv getframe