Re: Cumulative mean

[Francesco Potortì]

>Looking for something like cummax and cummin , is there a function to
>calculate the cumulative mean of a matrix / vector? I know it's an easy
>program to implement and I already made it on my own (as you may see in the
>attached file) , I just wanna know if there is a standard Octave function,
>which will be probably faster than mine.

I think that this is what you want:

octave> A=magic(4);A=horzcat(A,2*A)
A =

   16    2    3   13   32    4    6   26
    5   11   10    8   10   22   20   16
    9    7    6   12   18   14   12   24
    4   14   15    1    8   28   30    2

octave> cumsum(A)
ans =

   16    2    3   13   32    4    6   26
   21   13   13   21   42   26   26   42
   30   20   19   33   60   40   38   66
   34   34   34   34   68   68   68   68

octave> diag(1./(1:rows(A)))*cumsum(A)
ans =

   16.0000    2.0000    3.0000   13.0000   32.0000    4.0000    6.0000   26.0000
   10.5000    6.5000    6.5000   10.5000   21.0000   13.0000   13.0000   21.0000
   10.0000    6.6667    6.3333   11.0000   20.0000   13.3333   12.6667   22.0000
    8.5000    8.5000    8.5000    8.5000   17.0000   17.0000   17.0000   17.0000

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