>>> round((611.05/10.0),2)
61.1
>>> round((611.05/10.0),3)
61.105
How can I get 61.11 ?
I tried with following but results are same
>>> ctx = decimal.getcontext()
>>> ctx.rounding = decimal.ROUND_HALF_UP
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Bhavesh Odedra
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2Try `format(611.05 / 10.0, ".40f")` - it's `61.10499999999...`, slightly _less_ than the half you're trying to round up. – jonrsharpe Oct 12 '21 at 22:34
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1You can't get 61.11, because 61.1049 should never round to 61.11. Check this https://stackoverflow.com/questions/588004/is-floating-point-math-broken – Grismar Oct 12 '21 at 22:36
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Welcome to the world of floating point math https://0.30000000000000004.com/ – Samathingamajig Oct 12 '21 at 22:37
1 Answers
1
The decimal context is applied to decimal calculations:
from decimal import Decimal, ROUND_HALF_UP
non_rounded = Decimal("611.05")/Decimal("10.0")
non_rounded.quantize(Decimal(".01"), rounding=ROUND_HALF_UP)
Returns
Decimal('61.11')
EDIT: using quantize instead of round reference
luigibertaco
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This is working great in python3.x. But not in 2.x. It gives same. – Bhavesh Odedra Oct 12 '21 at 22:53
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1Decimals have their own rounding methods, I've updated the snippet with a working version on my py27 and py36 – luigibertaco Oct 12 '21 at 23:23