how to range data and find maximum value for each range by using loop

AB=[1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16; 10 5 7 8 3 18 20 3 6 66 2 14 39 40 4 20]

AB=transpose(AB)

I have data (AB) consisting of two columns. The number of rows of this data is 16. I want to divide this number into (1: 4: 16) and take the maximum values for each period ''depend on second column'' (with index firsr column), also i want to index the firt colum).

so the results will be,

[1 10

7 20

10 66

14 40]

Answer 1

[Matt J]

AB=[1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16; 10 5 7 8 3 18 20 3 6 66 2 14 39 40 4 20].';

[maxval,i]=max(reshape(AB(:,2),4,[]),[],1,'linear');

result = [AB(i,1),maxval(:)]

result = 4×2

1 10 7 20 10 66 14 40

[abdullah al-dulaimi]

thank you so much :)