# How to split vector to columns based on index?

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Maaz Madha on 24 Feb 2021
Edited: KALYAN ACHARJYA on 24 Feb 2021
Hi all
Hi all
How do I split this vector in such a way that everytime the consecutive value is less than the one before the vector would split into different columns based on that index. I've tried writing this code to get the index of where the change happens but it doesnt work and I don't know how to split the vector into different columns.
for k=1:length(SOC2_stop)
if SOC2_stop(k+1)<SOC2_stop(k)
index(k)=k;
end
end
##### 1 CommentShowHide None
Bob Thompson on 24 Feb 2021
I recommend finding all of your desired breaks in one go with find.
index = (find(SOC2_stop(2:end)-SOC2_stop(1:end-1)<0))+1;
As for the splitting into new columns others probably have much fancier ways to accomplish that than I would, but if you want it all in one matrix then you're going to need to identify the maximum number of elements to fit in one column first.
nrows = max(index(2:end)-index(1:end-1));
newarray = nan(nrows,numel(index)+1);

KALYAN ACHARJYA on 24 Feb 2021
Edited: KALYAN ACHARJYA on 24 Feb 2021
diff_data=diff(column_data);
idx=find(diff_data<0)
idx gives the indices of raspective array elements, where present value is greater than next one. Afterwards, use the mat2cell function to segemnt the array in different cell array elements (Cell array is useful to save multiple arrays with different sizes).
##### 2 CommentsShowHide 1 older comment
KALYAN ACHARJYA on 24 Feb 2021
Please see the mat2cell function in MATLAB Doc (Do Google)
Other Way using loop (Not so efficient)
result=cell(1,length(idx))
for i=1:length(idx)-1
result{i}=data(idx(i):idx(i+1)-1);
end
result{end}=data(idx(end):length(data));
result