A dot in the place of a subscript indicates summation over that index (How to code this?)

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AI
AI 2011-10-10
Dear Community members,
I've been trying to code the following notation in Matlab but have not been successful... any idea?
T-of(i.) = SIGMA-of(j)T-of(ij)
From the article: We maintain the convention introduced earlier that a dot in the place of a subscript indicates summation over that index. Thus (above formula) will represent everything leaving i during the unit time interval should become apparent.
The article's title is "Quantifying sustainability: Resilience, efficiency and the return of information theory" if anyone is interested.
Many thanks and I look forward to your comments and suggestions.

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Wayne King
Wayne King 2011-10-10
That just means they're summing over the columns. You can do that with
X = randn(10,10);
sum(X,2)
% note each element in the above is
for ii = 1:size(X,1)
SumAlongCols(ii) = sum(X(ii,:));
end

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