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Topic: Average the same elements of the list
Replies: 4   Last Post: May 24, 2013 5:24 AM

 Messages: [ Previous | Next ]
 Tomas Garza Hernandez Posts: 264 Registered: 4/15/05
Re: Average the same elements of the list
Posted: May 23, 2013 3:55 AM

Elegance is often a matter of individual taste (it lies in the eyes of the
beholder?), but a possible way is
datanew:=If[data[[1,1]]==data[[2,1]],{data[[1,1]],Mean[{data[[1,2]],data[[2,2]]}]},data]
data={{{1,2,3},4},{{1,2,3},5}}{{{1,2,3},4},{{1,2,3},5}}
datanew{{1,2,3},9/2}
data={{{1,1,3},4},{{1,2,3},5}}{{{1,1,3},4},{{1,2,3},5}}
datanew{{{1,1,3},4},{{1,2,3},5}}
-Tomas
> From: bipsich101@gmail.com
> Subject: Average the same elements of the list
> To: mathgroup@smc.vnet.net
> Date: Wed, 22 May 2013 02:18:09 -0400
>
> Hello,
> I have list which is something like
> data={
> {{a1,b1,c1},d1},{{a2,b2,c2},d2}}
> I would like to get new list which gets average of the second elements if the first elements in the sublists are all the same.
> Namely if a1=a2,b1=b2,c1=c2
> new list would look like
> datanew={{a1,b1,c1},Mean[{d1,d2}]
> Is there an elegant way to do this ?
> Thanks!
>

Date Subject Author
5/23/13 Bob Hanlon
5/23/13 Tomas Garza Hernandez
5/23/13 Murray Eisenberg
5/24/13 Daniel