Date: Jan 28, 2013 6:53 AM
Author: Barry Shaw
Subject: Re: Cumulative sum
for i = 1 : 5

if issorted(flipud(hewson([1:2],i))) %assumes that you only care about top 2 elements

hewson(:,end+1) = cumsum(hewson(:,i),1)

end

end

hewson =

1 5 8 4 7 8

3 6 4 7 9 12

3 6 7 9 5 19

2 5 6 7 5 25

Barry

"sam" wrote in message <ke5kpo$gjt$1@newscl01ah.mathworks.com>...

> I am new to Matlab and trying to create a a fairly simple matrix. one of my columns i want to be the cumualtive sum of another column. For example the below matrix, i want the next column (6) to be the cumulative sum of column 3 as it decends. so the first number will be 8 then the second number will be (8+4) 12 then the third will be (8+4+7) 19 and so on.

>

> 1 5 8 4 7

> 3 6 4 7 9

> 3 6 7 9 5

> 2 5 6 7 5

>

> i havetried various ways such as the one below but with no success, can anyone please tell me where i am going wrong?

> hewson is the name of my matrices

>

> for r = 1:20

> for c=6

> hewson (r,c) = cumsum(r,3);

> end

> end

>

> Many Thanks

> sam