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Re: Intersection problem

• To: mathgroup at smc.vnet.net
• Subject: [mg125996] Re: Intersection problem
• From: Christoph Lhotka <christoph.lhotka at fundp.ac.be>
• Date: Thu, 12 Apr 2012 02:33:40 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201204100627.CAA10654@smc.vnet.net>

hello,

here is one solution:

list1 = {{a, x}, {b, y}, {c, z}};
list2 = {b, c, d};

Select[list1, Intersection[list2, #] != {} &]
{{b, y}, {c, z}}

best,

christoph

On 04/10/2012 08:27 AM, Cisco Lane wrote:
> I need to select out the elements of the first list whose first elements are contained in the second list. For example
>
> first list: {{a,x},{b,y},{c,z}}
>
> second list: {b,c,d}
>
> result: {{b,y},{c,z}}
>
> Is there a quick way to do this? Intersection, maybe somehow?
>

• References:
  • Intersection problem
    • From: Cisco Lane <travlorf@yahoo.com>