Re: Warning from Piecewise
- To: mathgroup at smc.vnet.net
- Subject: [mg61539] Re: Warning from Piecewise
- From: "Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de>
- Date: Sat, 22 Oct 2005 00:35:23 -0400 (EDT)
- Organization: Uni Leipzig
- References: <dja298$fhh$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
what does Verbatim[] ?? when you do that:
Comm[Verbatim[Piecewise][A : {{_, _} ..}],
Verbatim[Piecewise][B : {{_, _} ..}]] :=
Comm[Testy[A], Testy2[B]]
Regards
Jens
"Chris Rodgers"
<rodgers at physchem.NOSPAMox.aREMOVEc.uk> schrieb im
Newsbeitrag news:dja298$fhh$1 at smc.vnet.net...
| Hi,
|
| When I try to set a delayed expression like
this:
|
| Comm[Piecewise[A:{{_, _}..}], Piecewise[B:{{_,
_}..}]] :=
| Comm[Testy[A], Testy2[B]]
|
| I get a warning from Piecewise that says:
|
| Piecewise::pairs: The first argument A : {{_, _}
..} of Piecewise is not
| a list of pairs.
|
| I thought that the HoldAll attribute on
SetDelayed should prevent
| evaluation of the LHS argument, so where is this
warning coming from?
|
| Can I ignore a warning like this, or should I
instead use a different
| sort of pattern?
|
| Many thanks,
|
| Chris Rodgers.
|