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[sagesupport] Re: Simplification Issue Implicates Canonical Form Mark Rahner Tue Feb 21 14:01:08 2012
> So once it comes back to Sage, its internal representation goes back to the > Ginac one. Doh! So much for a possible workaround involving maxima. Dox, I was using full_simplify() and also the handful of simplify methods it invokes. Evaluate "a.full_simplify?" to see their names. Nils, trivial comparison is a major reason to use a canonical form but it isn't an argument that favors a particular canonical form. For example, to simplify your example expressions, I would factor the 6 inside the radical and continue with substitutions as I recommended. The resulting expressions would be easy to compare because they would be identical: 2/sqrt(6) > 2/(sqrt(3)*sqrt(2)) > sqrt(2)/sqrt(3) sqrt(6)/3 > (sqrt(3)*sqrt(2))/3 > sqrt(2)/sqrt(3) My initial problem was the severe obfuscation that resulted when extra factors added by the canonical form refused to cancel and then replicated geometrically. Severe obfuscation is obviously a bad thing. It grows out of simple obfuscation of much simpler expressions. Should "( 1/7 * sqrt(21) ).full_simplify()" produce "1/7*sqrt(3)*sqrt(7)" when "sqrt(3)/sqrt(7)" is an option? Having fewer factors is an important part of being simpler. In the more complicated expression, the factors involving 7s aren't even adjacent. I don't know if the more complicated forms are required for GiNaC to perform efficiently. However, from an interactive user's perspective, this issue is perplexing because it only involves the representation of constants. What could be simpler? (pun intended) Mark  To post to this group, send email to [EMAIL PROTECTED] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sagesupport URL: http://www.sagemath.org
 [sagesupport] Simplification Issue Implicates Canonical Form Mark Rahner 2012/02/17
 [sagesupport] Re: Simplification Issue Implicates Canonical Form kcrisman 2012/02/17
 [sagesupport] Re: Simplification Issue Implicates Canonical Form Mark Rahner 2012/02/18
 [sagesupport] Re: Simplification Issue Implicates Canonical Form Dox 2012/02/20
 [sagesupport] Re: Simplification Issue Implicates Canonical Form kcrisman 2012/02/20
 [sagesupport] Re: Simplification Issue Implicates Canonical Form Nils Bruin 2012/02/20
 [sagesupport] Re: Simplification Issue Implicates Canonical Form Mark Rahner 2012/02/21 <=
 [sagesupport] Re: Simplification Issue Implicates Canonical Form JamesHDavenport 2012/02/22
 [sagesupport] Re: Simplification Issue Implicates Canonical Form Mark Rahner 2012/02/22
 [sagesupport] Re: Simplification Issue Implicates Canonical Form JamesHDavenport 2012/02/22