# summations and selections of the columns of a matrix

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I have a matrix of this type
10 15 37 16
6 4 3 5
15 66 85 96
17 89 15 82
58 66 78 100
I have to understand how to do two procedures:
1) calculate the sums of the subsequent column numbers, for example :
the first line remains the same 10 15 37 16
the second line must be 6+15+17+58 4+66+89+66 3+85+15+78 5+96+82+100
the third line must be 5+17+58 66+89+66 85+12+78 6+82+100
and so on ... can someone tell me how it can be done?
2) in the script then I have to consider the last one formed by as the first column
16
5
96
85
100
as the second column
37
3
85
15
78
and so on .. how do you select any column of the matrix you can use?
##### 2 CommentsShowHide 1 older comment
ELISABETTA BILLOTTA on 28 Oct 2021
perfect thank you very much!!!!

David Hill on 28 Oct 2021
newMatrix=[yourMatrix(1,:);flipud(cumsum(flipud(yourMatrix(2:end,:))))];
ELISABETTA BILLOTTA on 28 Oct 2021
ok thanks ... I understand that is the answer to point 1 and it works .. thanks a lot .. and for point two?