# I need to make groups from array

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zhoug zho on 30 Jun 2021
Edited: zhoug zho on 1 Jul 2021
I have this array, I need to make groups of these 14 elements with the rule that if value of a new element is 1 to 5 percent higher than the value of previous elements then the new element will be part of previous group, otherwise new group will start if it is higher than 5%. Thanks
zhoug zho on 30 Jun 2021
can you give an example based on our discussion, . then i will try to adjust the loop according to my need.

Walter Roberson on 30 Jun 2021
A = [.06, .18, .15, .14, .13, .12, .125, .15, .105, .115, .34, .32, .03 .14]
A = 1×14
0.0600 0.1800 0.1500 0.1400 0.1300 0.1200 0.1250 0.1500 0.1050 0.1150 0.3400 0.3200 0.0300 0.1400
mask = A(2:end) > 1.05 * A(1:end-1);
group_lengths = 1×6
1 6 2 1 3 1
mat2cell(A, 1, group_lengths)
ans = 1×6 cell array
{[0.0600]} {[0.1800 0.1500 0.1400 0.1300 0.1200 0.1250]} {[0.1500 0.1050]} {[0.1150]} {[0.3400 0.3200 0.0300]} {[0.1400]}
zhoug zho on 1 Jul 2021
Edited: zhoug zho on 1 Jul 2021
got it... Thank you so much.

David Hill on 30 Jun 2021
Some guessing. You only said it stays in group is greater by 1-5%, I assumed a new group otherwise. Anyways, you modify the below to meet your needs.
n{1}=yourArray(1);
c=1;
for k=2:length(yourArray)
if yourArray(k)<=1.05*yourArray(k-1)&&yourArray(k)>=1.01*yourArray(k-1)
n{c}=[n{c},yourArray(k)];
else
c=c+1;
n{c}=yourArray(k);
end
end
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Walter Roberson on 30 Jun 2021
However, if it is lower it needs to stay with the group being built according to https://www.mathworks.com/matlabcentral/answers/868868-i-need-to-make-groups-from-array#comment_1613113 and that means that you should not be testing against a lower bound. The 1% is a red herring; the only question is more than 5% increase (new group) otherwise continue the same group.