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skitapa
Oct9-09, 01:45 PM
I have a list L={a_{1}, ..., a_{n}}. I would like to find the mean of
L_{i} := {a_{1}, ... , a_{i}} for each 1<i<n, and then plot the means.
How do to do that in a smart way?

Hepth
Oct9-09, 05:04 PM
I'm not suite sure what you're asking but there are build in mean funcitons.

So couldn't you do something like :

MeanList= List[Mean[L[i]],{i,0,n}]
ListPlot[MeanList]

skitapa
Oct9-09, 05:15 PM
The L_{i} can be constucted by the Take function. But it seems hard to plot the means afterwards. Thats the real problem, how to get something that can be plotted

Hepth
Oct9-09, 05:39 PM
Well, your means will be scalars, one for each list, yes? well, make a list out of them and listplot.

Hepth
Oct9-09, 05:43 PM
L = {11, 12, 13, 14, 15, 16}
MeanList = Table[Mean[Take[L, i]], {i, 1, 6}]
ListPlot[MeanList]

skitapa
Oct9-09, 05:56 PM
Thank you very much.
I did generate the means by:For[i = 1, i < 1000, i++, Print[Mean[Take[R, i]]]]
and from there I was not able to make a list will all the means. Anyhow, your way was way better.