loop through field in a matlab struct array

Question

I have a MatLab struct array as follow:

'country.source.scenario.category.entity= year'

I would like to loop over the existing 'country.source.scenario' combinations and produce cell or matrix containing the fields: category, entity and year. Anyone as an idea about how to do that? Thanks

please provide a short example of what your input looks like and what is your expected output — Shai
– Shai, Commented Aug 6, 2015 at 13:05
@Shai - My input is a tree if data going from "countries" to "sources" to "scenarios" to "categories" to "entities" ending with "years" contained in a <x*x double>. Basically I have all kind of combinations (e.g. USA.CRF.HISTORY.CAT0.CH4= 2000 2001 2002). From that i would like to lock the existing COUNTRY.SOURCE.SCENARIO combination (such as USA.CRF.HISTORY) and build tables (or whatever other outputs) containing CATEGORY and ENTITY as X and Y and filled with the corresponding years. — steve
– steve, Commented Aug 6, 2015 at 13:13

A Hernandez · Accepted Answer · 2015-08-06 15:48:45Z

1

You can use fieldnames to get the fields at each level, and isstruct at each sublevel to see if you need to keep drilling, e.g.

fields = fieldnames(str);
for field = fields'
    sub = str.(field{1});
    if isstruct(sub)
        %loop through fieldnames
    end
end

You can put it in a recursive function whereby inside the if you again call the function. I did not do it like that because it was not clear to me what you wanted as a result, it seemed like you only wanted the tags and not the values at the end.

answered Aug 6, 2015 at 15:48

A Hernandez

4842 silver badges7 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

steve Over a year ago

@A Hernandez Thank you for your input! I was just doing that way: for fieldidx=1:length(fields) fieldname=fields{fieldidx}; if isstruct(struct.(fieldname)) but at some point I have any idea about how to organize the loop. At the end I would like to have an output (table) listing for the CATEGORIES as an header row, and ENTITIES as an header line and filled with the YEAR of each CATEGORIES.ENTITIES combinations!

Collectives™ on Stack Overflow

loop through field in a matlab struct array

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related