Le vendredi 13 septembre 2013 16:50:41 UTC+2, Volker Braun a écrit : > > > In Sage, parents pretty much need to be "logically" immutable. You can > certainly add cached data (that can be derived from the originial input) > but you shouldn't modify them in a way that makes them mathematically > different. >
Precisely, adding a new chart does not modify mathematically the manifold: it amounts to consider a specific chart in the manifold's maximal atlas. So would this type of "logical" immutability be OK ? I have to study deeper Sage's Parent/Element implementation. It seems that some starting points are http://www.sagemath.org/doc/reference/categories/sage/categories/primer.html http://www.sagemath.org/doc/reference/coercion/index.html Are there any other document that you would recommend ? Thank you for your help. Eric. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/groups/opt_out.
