How do I add a new field to an array of structures?

In my experiment I have one structure per subject I test. Each structure is quite complicated with many substructures e.g.:

sub.method1.result1

sub.method2.result1

sub.method2.result2

sub.method3.resulttype1.result1

sub.method2.resultstype2.result1 etc.

I have added all these structures together in an array of structures, lets call it aos, so that aos(1) will give me the structure for subject 1, aos(2) the structure for subject 2 etc. I then convert to tables to get a subset of the fields for all subjects to do my data analysis on. However, I now have an extra method that I would like to add to all the structures in the array. How can I do this? As I understand, all structures in an array of structures must have the same fields even though the fields do not need to contain the same type of data. So how do I add new fields to all the structures simultaneously in an array of structures?

Answer 1

[KSSV]

S = struct ;

S(1).name = 'Tom' ;
S(1).Age = 23 ;
S(1).sex = 'M' ;

S(2).name = 'Dick' ;
S(2).Age = 24 ;
S(2).sex = 'M' ;

S(3).name = 'Hary' ;
S(3).Age = 25 ;
S(3).sex = 'M' ;
% Add height to all structures arrays
C = num2cell([5 6 7]);
[S(:).height] = deal(C{:})

[Anna Lind]

Thanks so much :).

The only problem for me now is that I cannot get that to work on the substructures, so what I really want til do is e.g.:

S(1).name.first='Tom' S(2).name.first='Harry'

lastNames={'Jones','Potter'} [S(:).names.last]=deal(lastNames{:})

However, this does not work and I get the error: Expected one output from a curly brace or dot indexing expression, but there were 2 results.

[Guillaume]

Unfortunately, with multilevel structures you don't have a choice but to use explicit loops to do what you want:

for idx = 1:numel(lastNames)
   S(idx).name.last = lastNames{idx};
end

In addition, indeed in a structure arrays all elements of the arrays ust have the same fields. However, note that if these fields are themselves structures, these substructures do not have to have the same fields. You can for example have:

S(1).name.first = 'Tom'; 
S(2).name.first = 'Harry';
S(1).name.last = 'Jones';
%no 'last' field for S(2).name

[Anna Lind]

Ah, great! I get it know. Thank you both so much for your help :-)

[Royi Avital]

What about adding empty field (No values to it)?

[Guillaume]

s(1).name.emptyfield = [];