extract structure array value

Hi all

I have nested structure like below,

MyData(1).User.Id = 5;
MyData(1).User.Name = 'XXX';

MyData(2).User.Id = 7;
MyData(2).User.Name = 'XXX';

MyData(3).User.Id = 8;
MyData(3).User.Name = 'XXX';

MyData(4).User.Id = 9;
MyData(4).User.Name = 'XXX';

MyData(5).User.Id = 75;
MyData(5).User.Name = 'XXX';

MyData(6).User.Name = 45;
MyData(6).User.data = 'XXX';

I need output out = [5,7,8,9,75,45]

without loop i need to output.

if any body know inbuild command for that.

Thanks in advance.

[Stephen Cobeldick]

After fixing the mismatching fieldnames, you can use comma-separated lists like this:

>> tmp = [MyData.User];
>> out = [tmp.Id]
out =
    5    7    8    9   75   45

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/320713-how-to-operate-on-comma-separated-lists

[Murugan C]

It work fine... Thanks

Answer 1

[Rik]

You can hide the loop with arrayfun, but be aware that a good loop is always better than cellfun or arrayfun. You should ask yourself why you want to avoid loops.

MyData(1).User.Id = 5;
MyData(1).User.Name = 'XXX';
MyData(2).User.Id = 7;
MyData(2).User.Name = 'XXX';
MyData(3).User.Id = 8;
MyData(3).User.Name = 'XXX';
MyData(4).User.Id = 9;
MyData(4).User.Name = 'XXX';
MyData(5).User.Id = 75;
MyData(5).User.Name = 'XXX';
MyData(6).User.Id= 45;%correcting assumed typo
MyData(6).User.Name= 'XXX';%correcting assumed typo

arrayfun(@(s) s.User.Id,MyData)

It is also possible to avoid arrayfun:

tmp=[MyData.User];[tmp.Id]
%R2020a and later:
[horzcat(MyData.User).Id]

Answer 2

[madhan ravi]

You need to use a loop.

Note

Answer 3

[Fangjun Jiang]

%% correct data first
MyData(6).User.Id= 45;
MyData(6).User.Name= 'XXX';

%% then
A=struct2array(MyData);
result=[A.Id];