## Declaring TypesThe idea that one should be able to "declare the type" of a variable in Axiom by the command fricas n:PositiveInteger Type: Voidis a frequent expectation of new users of Axiom - especially if one has used other computer algebra systems, after all Axiom is supposed to be a "strongly typed" system, right? Unfortunately Axiom does not attempt to use this type information when forming expressions - but worse - declaring the type actually interferes with the use of the variable to form expressions! fricas n+1 When you write To me, this is a tremedous waste of an opportunity in Axiom to to deal with "domain of computation" issues such as are addressed in other untyped computer algebra systems by the use of "assumptions" such as: assume(x,PositiveInteger); Such knowledge can be used to considerably improve the quality and generality of the computations. There was plenty of discussion on axiom-developer, but no concensus yet, I'm afraid. Here are some of the related threads: - http://lists.gnu.org/archive/html/axiom-developer/2004-06/msg00191.html
- http://lists.gnu.org/archive/html/axiom-developer/2004-06/msg00212.html
- http://lists.nongnu.org/archive/html/axiom-developer/2006-09/msg00518.html
- http://lists.nongnu.org/archive/html/axiom-developer/2006-09/msg00549.html
See also The Unknown In Computer Algebra The Unknown In Computer Algebra spad )abbrev domain PUNINT PureUnknownInteger PureUnknownInteger (D, spad Compiling FriCAS source code from file /var/lib/zope2.10/instance/axiom-wiki/var/LatexWiki/7349452271109161057-25px003.spad using old system compiler. PUNINT abbreviates domain PureUnknownInteger ******** Spad syntax error detected ******** Expected: |)| The prior line was: |

pdf format--Bill Page, Tue, 19 Sep 2006 09:21:21 -0500 reply