Re: how to build pattern for a square matrix of reals?
- To: mathgroup at smc.vnet.net
- Subject: [mg98396] Re: how to build pattern for a square matrix of reals?
- From: Albert Retey <awnl at gmx-topmail.de>
- Date: Thu, 9 Apr 2009 05:51:27 -0400 (EDT)
- References: <grhp95$mj7$1@smc.vnet.net>
sagrailo at gmail.com wrote:
> As in subject: how to build a pattern that will specify that given
> argument of a function has to be square matrix of reals? Tried with
> following for "square matrix" part:
> f[x_?MatrixQ[#] && Dimensions[#][[1]] == Dimensions[#][[2]]
> &] := ...
> but it doesn't seem to be working...
>
> Thanks.
you are just missing some brackets:
f[x_?((MatrixQ[#] &&
Dimensions[#][[1]] == Dimensions[#][[2]]) &)] := "match"
hth,
albert