Re: Intersection problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg125992] Re: Intersection problem*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Wed, 11 Apr 2012 18:21:32 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

On 4/10/12 at 2:27 AM, travlorf at yahoo.com (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? In[1]:= Cases[{{a, x}, {b, y}, {c, z}}, _?(Intersection[#, {b, c, d}] != {} &)] Out[1]= {{b, y}, {c, z}}