Split an array using specific points
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Just starting out in matlab and would appreciate your help.
for example : lets say I have an array Y = [5;2;3;6;7;9;5;5;6;3;8;7;74;9;63;47;10;3]; and another array of index diiv = [5;9;15];
How can i use diiv to break Y into smaller arrays so I would get as output arrays y1 = [5;2;3;6;7], y2 =[9;5;5;6]; y3 =[3;8;7;74;9;63]; y4=[47;10;3]
Thanks
1 Comment
Stephen23
on 2 Mar 2022
Edited: Stephen23
on 2 Mar 2022
If you are numbering your variables like that then you are doing something wrong.
If you are trying to access variable names dynamically then you are doing something wrong.
Simple and efficient MATLAB code uses arrays and indexing. You should use arrays and indexing.
Accepted Answer
Stephen23
on 2 Mar 2022
Edited: Stephen23
on 2 Mar 2022
Simpler and more efficient than what you are attempting (although most likely you don't realise that yet):
Y = [5;2;3;6;7;9;5;5;6;3;8;7;74;9;63;47;10;3];
diiv = [5;9;15];
D = diff([0;diiv;numel(Y)]); % complete the missing data
C = mat2cell(Y,D,1) % split into a cell array
C{:}
2 Comments
More Answers (2)
Alan Stevens
on 1 Mar 2022
Like this?
Y = [5;2;3;6;7;9;5;5;6;3;8;7;74;9;63;47;10;3];
diiv = [5; 9; 15];
y1 = Y(1:diiv(1));
y2 = Y(diiv(1)+1:diiv(2));
y3 = Y(diiv(2)+1:diiv(3));
y4 = Y(diiv(3)+1:end);
2 Comments
Stephen23
on 2 Mar 2022
Edited: Stephen23
on 2 Mar 2022
"is it possible to do this automatically (like in a loop) without writing out each expression for y1, y2,y3,y4"
It is certainly possible, but only if you want to force yourself into writing slow, complex, inefficient code which is buggy and hard to debug:
In contrast the neat, simple, and very efficient MATLAB approach is to use indexing.
Tip: if you are numbering your varaible names like that, then you are doing something wrong.
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