Greg Ewing wrote: > M.-A. Lemburg wrote: > >> I suppose you don't know about the optional argument >> to round that lets you round up to a certain decimal ?! > > Yes, I know about, but I rarely if ever use it. > Rounding a binary float to a number of decimal > places seems a fundamentally ill-considered thing > to do anyway. What are the use cases for it, > given that one can easily select a number of decimal > places when formatting a number for display?
You often have a need for controlled rounding when doing financial calculations or in situations where you want to compare two floats with a given accuracy, e.g. to work around rounding problems ;-) The usual approach is to use full float accuracy throughout the calculation and then apply rounding a certain key places. Float formatting is an entirely different issue. >> If we were to follow your suggestion, we'd have round() >> return an integer when called without the argument and >> a float when called with the argument. > > No, round() wouldn't have that option at all. If > you wanted it, you would use fround() instead, > which would have the option and return a float > always. > > This would be a Py3k thing, obviously. If done > before then, the new function would have to be > given a different name. Hmm, looks like a YAGNI to me, but perhaps I'm missing something :-) -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Aug 01 2006) >>> Python/Zope Consulting and Support ... http://www.egenix.com/ >>> mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ >>> mxODBC, mxDateTime, mxTextTools ... http://python.egenix.com/ ________________________________________________________________________ ::: Try mxODBC.Zope.DA for Windows,Linux,Solaris,FreeBSD for free ! :::: _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
