On Dec 4, 2007 1:08 PM, David Benbennick <[EMAIL PROTECTED]> wrote: > On Dec 4, 2007 9:21 AM, Steven Fodstad <[EMAIL PROTECTED]> wrote: > > For the index, how about this: > > > > truncate . (/(log 2)) . log . fromIntegral > > That will not work. It will convert the Integer to Double, which will > overflow if the Integer is very large.
I think this is further evidence for Sage's need for an equivalent for Maple's "ilog" and Mathematica's "IntegerLength" function, with base 2 handled as the most important special case. (See e.g. http://reference.wolfram.com/mathematica/ref/IntegerLength.html.) What to call it is a bit of a question; I don't much like "integer logarithm" since that could be confused with the sum of multiplicities of the prime factors of an integer, or even a discrete logarithm. At first thought Mathematica's IntegerLength idea seems reasonable. Steve --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
