MathGroup Archive 2009

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

Search the Archive

Re: how to build pattern for a square matrix of reals?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg98452] Re: how to build pattern for a square matrix of reals?
  • From: Albert Retey <awnl at gmx-topmail.de>
  • Date: Fri, 10 Apr 2009 04:52:46 -0400 (EDT)
  • References: <grhp95$mj7$1@smc.vnet.net> <grkgmm$6kq$1@smc.vnet.net>

sagrailo at gmail.com wrote:
> Sorry, I still have some related issues: if I have say two vectors
> (lists) as function arguments, how to build pattern that will verify
> that the length of the second vector is equal to the size of the first
> vector?  Also, how to check that specific element of some vector have
> specific value?  I tried something like:
>   Foo[v1:{_Real..}/;Length[Dimensions[v1]]==1&&v1[[1]]==0,v2:
> {_Real..}/;Length[Dimensions[v2]]==1&&Dimensions[v2][[1]]==Dimensions
> [v1][[1]]]:="OK"
> but it doesn't work...

This is what I would do:

foo[v1_?(VectorQ[#, NumericQ] &), v2_?(VectorQ[#, NumericQ] &)] /;
  And[v1[[1]] == 0, Length[v1] == Length[v2]] := "OK"

hth,

albert


  • Prev by Date: Re: StringJoin with ToString
  • Next by Date: Re: escaping quote for use with a selectionplaceholder
  • Previous by thread: Re: how to build pattern for a square matrix of reals?
  • Next by thread: Re: how to build pattern for a square matrix of reals?