Matlab - Sumatoria

V=[2 3 2 1 5 6 3 4 5]

for a=1:length(V)/3

V2(a)=sum(V([a,a+3,a+6]));

end

V2

V =

     2     3     2     1     5     6     3     4     5

V2 =

     6    12    13

>> sumatoria

V =

     8     9     1     9     6     1     3     5    10

V2 =

    20    20    12

>> sumatoria

V =

    10     2    10    10     5     8     1     4     9

V2 =

    21    11    27

>> sumatoria

V =

     8    10     7     0     8     9     7     8     7

V2 =

    15    26    23

>> sumatoria

V =

     4     7     2     7     0     3     0     1     8

V2 =

    11     8    13

V=[10     6     3    14     1     2     2     2     9     9     1    14    11    11     1    13    14    15    13    12     8     3     6     2     0    14     5]

clear

V = [10 6 3 14 1 2 2 2 9 9 1 14 11 11 1 13 14 15 13 12 8 3 6 2 0 14 5]

for k=1:3

    s=0;

    for a=k:3:length(V)

        s=s+V(a);

    V2(k)=s ;

    end

end

V2

>> sumatoria1

V =

    10     6     3    14     1     2     2     2     9     9     1    14    11    11     1    13    14    15    13    12     8     3     6     2     0    14     5

V2 =

    75    67    59