Re: Types in Mathematica, a practical example
- To: mathgroup at smc.vnet.net
- Subject: [mg62855] Re: Types in Mathematica, a practical example
- From: "Steven T. Hatton" <hattons at globalsymmetry.com>
- Date: Tue, 6 Dec 2005 23:10:31 -0500 (EST)
- References: <dn22cf$ku4$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Ingolf Dahl wrote: > I am not allowed to Unset or Clear any part of a list either. Why not? I should probably look into this more carefully before commenting, but, at the risk of making an incorrect statement, I will say this. Lists and other entities in Mathematica are rewritten upon each evaluation. You never really modify an existing expression. Instead, you modify a copy, and assign the result to the original symbol. My explanation is almost certainly an oversimplification in need of refinement, but I believe it addresses the essence of your question. -- The Mathematica Wiki: http://www.mathematica-users.org/ Math for Comp Sci http://www.ifi.unizh.ch/math/bmwcs/master.html Math for the WWW: http://www.w3.org/Math/