[Python-Dev] Expert floats

[Greg Ewing]

Andrew Koenig <ark-mlist at att.net>:

> The reason is that the first example does arithmetic, and it is easy
> to explain that floating-point arithmetic is not completely accurate.

Then how would you explain this to them:

>>> 1.1 < 1.1000000000000001
False

There's no arithmetic being done there.

And if you're thinking of something like "floats don't have that
many digits of precision", you then need to explain

>>> 1.2 < 1.2000000000000001
True

Greg Ewing, Computer Science Dept, +--------------------------------------+
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