Loop over fieldnames in a MatLab structure - matlab

Question

I have a MatLab "struct", with different "level" and "sub-structures". When printed to a cell, the data contained in the "struct", look like that:
report.COUNTRY.SOURCE.SCENARIO.CATEGORY.ENTITY = YEAR YEAR ...;
As a minimal example:
report.HUN.CRF2014.BASEYEAR.CAT0.CO2 = 1991 1992 1993 1994
report.HUN.CRF2014.BASEYEAR.CAT0.CH4 = 1995 1996 1997
report.HUN.CRF2014.BASEYEAR.CAT0.H2S = 1990 1991 1992
report.HUN.CRF2014.BASEYEAR.CAT1.N2 = 1991 1992 1993
report.HUN.CRF2014.BASEYEAR.CAT1.FGASES = 1990 1991 1992
In order to produce tables listing the different variables combinations, I would like to loop over the fieldnames contained within the "struct".
I am currently trying to write a function able to do that:
fields=fieldnames(struct);
for categoryidx=1:length(fields)
categoryname=fields{categoryidx};
if isstruct(struct.(categoryname))
category=fieldnames(struct.(categoryname));
for entityidx = 1:length(category);
entityname = category{entityidx};
if isstruct(struct.(categoryname).(entityname))
gases=fieldnames(struct.(categoryname).(entityname));
end
end
end
end
Unfortunately, this is just producing anything! Does anyone has any idea how to loop over fieldnames in such a matlab structure? Thank you!

Answer 1

You might want to check out:
struct2tabler. This is a MATLAB function that recursively goes through a structure to convert into a table.
For example:
a.a = 5
a.b.c = 10
a.b.d = 15
Would return a table:
a_a a_b_c a_b_d
---------------------------
5 10 15
Disclaimer: I have written struct2tabler, so might be a little biased, however it was created out of a requirement, I think, very similar to yours.