Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2010

[Date Index] [Thread Index] [Author Index]

Search the Archive

Pattern to match a list of non-negative integers

  • To: mathgroup at smc.vnet.net
  • Subject: [mg108919] Pattern to match a list of non-negative integers
  • From: Leo Alekseyev <dnquark at gmail.com>
  • Date: Wed, 7 Apr 2010 03:20:21 -0400 (EDT)

This seems like a very basic pattern-matching question, but somehow
the answer eludes me at the moment.  I want to match a list of
non-negative integers.  Something like MatchQ[{1,2},{(x_Integer /; x
>= 0)..}] doesn't work -- do named patterns simply not play well with
Repeated[]?..

After starting to write this message, the following pattern, occurred to me:
MatchQ[{2, 3}, x : {_Integer ..} /; ! MemberQ[x, y_ /; Negative[y]]]
-- this works, but seems needlessly complex -- so I'll send the
message on, in hopes that there is a cleaner way of writing the
pattern.


  • Prev by Date: Re: Will FindFit invoke LinearProgramming?
  • Next by Date: Re: convert txt to binary file
  • Previous by thread: Re: Multiple Window Feature Request
  • Next by thread: Re: Pattern to match a list of non-negative integers