[Python-Dev] Numerical robustness, IEEE etc. (original) (raw)

Aahz aahz at pythoncraft.com
Wed Jun 21 15:07:35 CEST 2006

On Wed, Jun 21, 2006, Nick Coghlan wrote:

Facundo Batista wrote:

BTW, prove me Decimal is not fast enough, ;) C:\Python24>python -m timeit -s "x = 1.0" "x+x" 10000000 loops, best of 3: 0.137 usec per loop C:\Python24>python -m timeit -s "from decimal import Decimal as d; x = d(1)" "x+x" 10000 loops, best of 3: 48.3 usec per loop I don't really know my definition of 'fast enough to be the basic floating point type', but I'm pretty sure that a couple of orders of magnitude slower isn't it. I guess I'll find out what my definition is if the C implementation manages to get there ;)

Why isn't that fast enough? Relative speed is not the issue when talking about real-world applications. More to the point, the expectation is that the C implementation of Decimal will have faster conversion to/from string, which in many real world applications forms a significant part of the processing load.

Aahz (aahz at pythoncraft.com) <*> http://www.pythoncraft.com/

"I saw `cout' being shifted "Hello world" times to the left and stopped right there." --Steve Gonedes

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