Re: Apply or Map on some parts of lists - help
- To: mathgroup at smc.vnet.net
- Subject: [mg115724] Re: Apply or Map on some parts of lists - help
- From: "andre.robin3" <andre.robin3 at wanadoo.fr>
- Date: Wed, 19 Jan 2011 05:27:09 -0500 (EST)
- References: <igrqdn$qot$1@smc.vnet.net>
Elegant, clear, and purely functional :
ReplacePart[list, x : {_, 2, _, 2} :> f[ Extract[list, x]]]
---> {
{{TITLE1}, {{x11, f[y11]}, {x12, f[y12]}, {x13, f[y13]}, {x14, f[y14]}}},
{TITLE1}, {{x21, f[y21]}, {x22, f[y22]}, {x23, f[y23]}, {x24, f[y24]}}},
{{TITLE1}, {{x31, f[y31]}, {x32, f[y32]}, {x33, f[y33]}, {x34, f[y34]}}}}
Or better (if each line contain more than 2 elements) :
ReplacePart[list, x : {_, Except[1], _, 2} :> f[ Extract[list, x]]]
"dragec" <culinovic at gmail.com> a écrit dans le message de news:
igrqdn$qot$1 at smc.vnet.net...
> Dear,
> I have
>
> List like:
>
> { {{TITLE1},{{x11,y11},{x12,y12},{x13,y13},{x14,y14}}},
> {{TITLE1},{{x21,y21},{x22,y22},{x23,y23},{x24,y24}}},
> {{TITLE1},{{x31,y31},{x32,y32},{x33,y33},{x34,y34}}}
> }
>
> So, I would like to apply some function (eg. #/3.6&) to all y's.
> Is there any elegant way to do this.
> I Know that you know how to do this. :)
>
> THX
>