Re: Selecting Many Things Rather Than Selecting One Thing From Many

*To*: mathgroup at smc.vnet.net*Subject*: [mg66218] Re: Selecting Many Things Rather Than Selecting One Thing From Many*From*: Bill Rowe <readnewsciv at earthlink.net>*Date*: Thu, 4 May 2006 05:21:00 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

On 5/3/06 at 2:44 AM, gregory.lypny at videotron.ca (Gregory Lypny) wrote: >I've discovered another use or need for the Select function, which I >suspect requires mapping of some sort. >In my previous posts, members of this MathGroup kindly showed me how >to apply Select to many columns of a matrix at once. For example, >(Select[#1, #1 > K & ] & ) /@ Transpose[theMatrix] >will pull out all values greater than K, where K is a number such as >100. >But suppose now that K is a list of numbers, such as K={34, 876, >199}, and I simply want to extract or identify all of the rows in >the first column of theMatrix equal to any one of those numbers. >How would I do that? I started with >Select[theMatrix, #[[1]]==any element of list K] Use Select[theMatrix, MemberQ[listK, #[[1]]]&] -- To reply via email subtract one hundred and four