On Wednesday, July 20, 2016 at 11:13:05 AM UTC+5:30, Steven D'Aprano wrote: > On Tuesday 19 July 2016 14:58, Rustom Mody wrote: > > > So I again ask: You say «"Never compare floats for equality" is a pernicious > > myth» > > It is the word *never* which makes it superstition. If people said "Take care > with using == for floats, its often not what you want" I would have no > argument > with the statement. > > I'd even (reluctantly) accept "usually not what you want". But "never" is out- > and-out cargo-cult programming.
You seem to not understand the realities of teaching. You (teacher in general) cannot say a saga; only epigrams You cannot transmit wisdom (even if you own some) just a bit of savviness/cleverness. So let me ask the question again differently: How many errors happen by people not using ε-neighborhood checks instead of == checks How many errors happen by the opposite (mis)use? IOW “myth”... ok “pernicious myth” Not BTW APL whose main domain of application is scientific chooses to enshrine this —equality is ε-neighborhood checking not exact equality checking — into its builtin ‘==’ And http://www.dyalog.com/uploads/documents/Papers/tolerant_comparison/tolerant_comparison.htm ε is spelt ⎕ct (Comparison Tolerance) And of course == is spelt = -- https://mail.python.org/mailman/listinfo/python-list
