On Mon, 18 Nov 2013 14:14:33 +0000, Kay Y. Jheallee wrote: > Using 1/3 as an example,
[snip examples] > which seems to mean real (at least default) decimal precision is limited > to "double", 16 digit precision (with rounding error). That's because Python floats actually are implemented as C doubles. And no, they're not configurable. However, Python also has a Decimal class, which (unlike floats) are actually decimal rather than binary, and include configurable precision. There is a performance hit -- prior to Python version 3.3, Decimal was quite slow, but in 3.3 they got a major speed increase and are now nearly as fast as floats. An example: py> import decimal py> x = decimal.Decimal(1)/3 py> decimal.getcontext().prec = 50 py> y = decimal.Decimal(1)/3 py> print(x, y) 0.3333333333333333333333333333 0.33333333333333333333333333333333333333333333333333 -- Steven -- https://mail.python.org/mailman/listinfo/python-list
