How to create table from struct array

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I would like to create table from imported json table.
The data imported are arranged in struct array, So I ould like to create table by combining fields and value in one table.

Accepted Answer

Stephen23
Stephen23 on 27 Apr 2021
Edited: Stephen23 on 27 Apr 2021
Note that mixing up meta-data (the date) into fieldnames forces superfluous nesting of structures. This poor data design has already allowed one bug into your data: dates with/without leading zeros has allowed duplicates, e.g. for 2021 both of "Apr1" and "Apr01" are listed, as are both of "Apr2" and "Apr02", and as are both of "Apr4" and "Apr04".
Much better data design would store the date as data in its own right: if you have the choice, store the data in an Nx1 structure with a date field (and store the date as datetime or a datevector or anything more robust than those strings).
But given what you have described:
F1 = struct('A',11,'B',12);
F2 = struct('A',21,'B',22);
F3 = struct('A',31,'B',32);
S = struct('Mar23_2021',F1, 'Apr2_2021',F2, 'Apr10_2021',F3)
S = struct with fields:
Mar23_2021: [1×1 struct] Apr2_2021: [1×1 struct] Apr10_2021: [1×1 struct]
F = fieldnames(S);
D = datetime(F,'InputFormat','MMMd_yyyy');
C = struct2cell(S);
T = struct2table(vertcat(C{:}));
T.date = D
T = 3×3 table
A B date __ __ ___________ 11 12 23-Mar-2021 21 22 02-Apr-2021 31 32 10-Apr-2021
  1 Comment
Doaa Alamoudi
Doaa Alamoudi on 28 Apr 2021
Thanks for your answer. The answer is for creating table, however, I have the table ready imported from JSON file and I would like to extract the data and analyze it.

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