%% Vector with NaN Values
% Create a vector containing NaN values and compute the cumulative sums. By default, cumsum includes NaN values. When you include NaN values in the calculation, the cumulative sum becomes NaN as soon as the first NaN value in A is encountered.

A = [3 5 NaN 9 0 NaN];
B = cumsum(A)

%
% You can ignore NaN values in the cumulative sum calculation using the 'omitnan' option.

B = cumsum(A,'omitnan')

% Copyright 2012 The MathWorks, Inc.