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Re: Pure function in a pure function (again)


On Sep 23, 2006, at 4:44 AM, Skirmantas Janusonis wrote:

> Hello,
>
> I've already asked this question, but I thought there was a better way 
> to state it. If Dat is a 2D-table, the following picks out the rows 
> whose first element is 1,2 or 3 and adds up their the second elements:
>
> f[x_] := Plus @@ Column[Select[Dat, #[[1]] == x &], 2]
> f /@ Range[3]
>
> Instead of f/@Range[3], I'd like to use a second pure function, 
> something like this:
>
> Map[Plus @@ Column[Select[Dat, #1[[1]] == #2 &], 2]&,Range[3]]
>
> This line is incorrect, however. How do I fix it?

Map[Function[x,Plus@@Column[Select[Dat,#1[[1]]==x&],2]],Range[3]]

Regards,

Ssezi


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