Re: Conditional drop of list elements
- To: mathgroup at smc.vnet.net
- Subject: [mg63574] Re: [mg63557] Conditional drop of list elements
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Thu, 5 Jan 2006 06:02:44 -0500 (EST)
- Reply-to: hanlonr at cox.net
- Sender: owner-wri-mathgroup at wolfram.com
list1={{0,A,A,A},{1,B,B,B},{0,C,C,C},
{1,D,D,D},{1,F,F,F},{0,G,G,G},{0,H,H,H}};
Select[list1,#[[1]]==1&]
{{1, B, B, B}, {1, D, D, D}, {1, F, F, F}}
Cases[list1,{1,___}]
{{1, B, B, B}, {1, D, D, D}, {1, F, F, F}}
list1/.{0,___}:>Sequence[]
{{1, B, B, B}, {1, D, D, D}, {1, F, F, F}}
Bob Hanlon
>
> From: "LectorZ" <lectorz at mail.ru>
To: mathgroup at smc.vnet.net
> Date: 2006/01/05 Thu AM 03:12:25 EST
> Subject: [mg63574] [mg63557] Conditional drop of list elements
>
> Hi guys,
>
> I need your assistance by the following problem:
>
> list1 = {{0,A,A,A}, {1,B,B,B}, {0,C,C,C}, {1,D,D,D}, {1,F,F,F},
> {0,G,G,G}, {0,H,H,H}}
>
> Every 1st element of the each sublist should be checked. Is the first
> element a ZERO, this sublist should be removed from the list. If it is
> a ONE - this sublist remains in the list.
>
> In this example the output should be:
>
> {{1,B,B,B}, {1,D,D,D},{1,F,F,F}}
>
> Thanks for your help!
>
> LZ
>
>