[Python-Dev] Expert floats (original) (raw)

Josiah Carlson jcarlson at uci.edu
Tue Mar 30 14:16:53 EST 2004

That doesn't make sense to me. If the .py file says "1.1" and the .pyc file says "1.1", you're going to get the same results.

In fact, you've just given a stronger reason for keeping "1.1". Currently, compiling a .py file containing "1.1" produces a .pyc file containing "1.1000000000000001". .pyc files are supposed to be platform-independent. If these files are then run on a platform with different floating-point precision, the .py and the .pyc will produce different results.

I believe (please correct me if I'm wrong), that Python floats, on all platforms, are IEEE 754 doubles. That is, Python uses the 8-byte FP, not the (arguably worthless) 4-bit FP. Cross-platform precision is not an issue.

More information about the Python-Dev mailing list