Re: transversal sum

[bearophile via Digitalmars-d-learn]

Marc Schütz:

        int[][] input = new int[][2];
        input[0] = [1, 2, 3, 4];
        input[1] = [5, 6, 7, 8];
        writeln(input);
        auto sums = input
                .transposed
                .map!(a => a.sum);
        writeln(sums);
    }

Output:

    [[1, 2, 3, 4], [5, 6, 7, 8]]
    [6, 8, 10, 12]

Jack specified:

I have rectangular forward range of forward ranges (not arrays):

You "input" range is not just a Forward Range.

And by the way, your array literal can be written more simply 
like this:

int[][2] input = [[1, 2, 3, 4], [5, 6, 7, 8]];

Bye,
bearophile