Selecting specific values from a structured array

Hi, I have a structured array with 10 fields, each one of which is a 8x1 array of symbolic values. Is there any way I can save to another array the 3rd value only of each one of these fields?

Answer 1

[Durga Yenikepalli]

Hi Oliver,

I understand that you want to select specific element from a structured array and save it to another array.

We can use ‘a = extractfield(S,name)’ function which returns the field values specified by the field name of structure s, and then try to extract 3rd element from the extracted field values and save to another array. Refer below code.

% Example code 
% structured array with 10 fields 
s = struct('f1', a1,'f2', a2, 'f3', a3, 'f4', a4, 'f5', a5,'f6', a6, 'f7', a7, 'f8', a8, 'f9', a9, 'f10', a10); 

% extracting field names 
fieldNames = fieldnames(s); 
 
% preallocating array for better performance 
finalArray = zeros(1,10); 
 
% iterate and extract 3rd value from each field 
for n =1:numel(fieldNames) 
    f = extractfield(s, fieldNames{n}); 
    finalArray(n) = f(3); 
end

https://www.mathworks.com/help/map/ref/extractfield.html?searchHighlight=extractfield&s_tid=srchtitle

Thanks.