Re: take square of the second and third column of a table

*To*: mathgroup at smc.vnet.net*Subject*: [mg124192] Re: take square of the second and third column of a table*From*: Tomas Garza <tgarza10 at msn.com>*Date*: Thu, 12 Jan 2012 04:20:22 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <201201112220.RAA22144@smc.vnet.net>

For example, b = Table[RandomInteger[{0, 9}], {10}, {3}];(avoid capitalizing your variables to prevent conflicts with Mathematica's own symbols) One possibility is as follows: {#[[1]], #[[2]]^2, #[[3]]^2} & /@ b This is functional programming, where you don't have t worry about table lengths and all that stuff. -Tomas > Date: Wed, 11 Jan 2012 17:20:16 -0500 > From: hanciong at gmail.com > Subject: take square of the second and third column of a table > To: mathgroup at smc.vnet.net > > Hello, suppose I have a very long table like this: > > 1 2 3 > 4 5 6 > 7 8 9 > ....... > 2 3 4 > > how can I take square of the 2nd and 3rd column? I always do it by > making a new table. so let's say the above table is A and it has 100 > lines, then I make the new table as the following: > > B=Table[{A[[n]][[1]],A[[n]][[2]]^2,A[[n]][[3]]^2},{n,1,100}] > > But if the length of the table is unknown, this way is impractical. > Could anyone suggests better way? thank you >

**References**:**take square of the second and third column of a table***From:*hanciong awesome <hanciong@gmail.com>