How do I create a matrix such as a matrix L of the data matrix M as shown below..?

I have matrix M below

M = [1 2 0.2
2 3 0.4
3 4 0.22
4 5 0.1
5 6 0.5]

How do I create a matrix such as a matrix L of the data matrix M as shown below..?

L = [0.2
(0.4+0.2)
(0.22+0.4+0.2)
(0.1+0.22+0.4+0.2)
(0.5+0.1+0.22+0.4+0.2)
]

Answer 1

[Image Analyst]

Try this:

L = cumsum(M(3:3:end))

[Jan]

Or

cumsum(M(:, 3))

[Image Analyst]

Right. That's what I had in her original question (a separate discussion thread), which was a 2-D matrix. This question used to be a row vector. Now she changed this one from a row vector to a 2-D matrix and somehow her other question, with the 2-D matrix that I answered exactly like you did, is now gone.