How can I extract points (sum of values) from variable size groups of lines (separated from NaN values) in the same column ?

Question

Mauricio Melati 2020-5-28

关闭： MATLAB Answer Bot 2021-8-20

Hi, here is my problem.

I have this two columns.

A=[1; 2; 5; NaN; 4; 6; 8; 65; 6; NaN; NaN; NaN; 33; 5; 7]

B=[5; 8; 5; NaN; 4; 7; 8; 66; 8; NaN; NaN; NaN; 32; 1; 7]

I want a new matrix with two coluns with the sum of each group (in each column) that is separated by NaN values sequences to develop a scatter graph.

Answer:

C=[8 18;89 93;45 40]

Thanks!

此问题已关闭。

Answer 1

Tommy 2020-5-28

Potentially over-complicated but should work:

cA = cumsum([A, B],'omitnan');
idx = [isnan(A(2:end)); 1] & ~isnan(A);
C = diff([0, 0; cA(idx,:)]);