Ronald Oussoren <[EMAIL PROTECTED]> wrote: > > > There are algorithms where the operation of rounding (or truncation) > > is needed, but where the value may be larger than can be held in an > > integer, and that is not an error. > > Is that really true for python? Python integers are unbounded in > magnitute, they are not the same as int or long in C, therefore any > float except exceptional values like NaN can be converted to an > integer value. The converse is not true, python integers can contain > values that are larger than any float (aka C's double).
It depends a great deal on what you mean by a Python integer! Yes, I was assuming the (old) Python model, where it is a C long, but so were many (most?) of the other postings. If you are assuming the (future?) model, where there is a single integer type of unlimited size, then that is true. There is still an efficiency point, in that such algorithms positively don't want a float value like 1.0e300 (or, worse, 1.0e4000) expanded to its full decimal representation as an intermediate step. Whatever. There should still be at least one operation that rounds or truncates a float value, returning a float of the same type, on either functionality or efficiency grounds. I and most programmers of such algorithms don't give a damn which it does, provided that it is clearly documented, at least half-sane and doesn't change with versions of Python. Regards, Nick Maclaren, University of Cambridge Computing Service, New Museums Site, Pembroke Street, Cambridge CB2 3QH, England. Email: [EMAIL PROTECTED] Tel.: +44 1223 334761 Fax: +44 1223 334679 _______________________________________________ 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
