RE: Subsetting indexed variable?
- To: mathgroup at smc.vnet.net
- Subject: [mg36043] RE: [mg36028] Subsetting indexed variable?
- From: "DrBob" <majort at cox-internet.com>
- Date: Wed, 14 Aug 2002 05:35:11 -0400 (EDT)
- Reply-to: <drbob at bigfoot.com>
- Sender: owner-wri-mathgroup at wolfram.com
Try (DownValues@b)[[All, 2]] Bobby Treat -----Original Message----- From: Gareth J. Russell [mailto:gjr2008 at columbia.edu] To: mathgroup at smc.vnet.net Subject: [mg36043] [mg36028] Subsetting indexed variable? Hi, I cannot seem to work out how to extract a subset of information from an indexed variable (without generating a full list/matrix first). For example, suppose I define: b[1,3] = 3 b[2,3] = 7 b[2,4] = 5 And I then want to get the list of all DEFINED values of b[2,_], i.e., the result should be {7,5} Help appreciated! Gareth ========================================================== Dr. Gareth J. Russell Columbia University E-mail: gjr2008 at columbia.edu ==========================================================