Message312547
This isn't a bug. When you do `Decimal(9.95)`, you're converting the binary floating-point number `9.95` to a `Decimal` instance. The conversion is performed exactly, with no change in the value. But the *input* to the conversion, the float `9.95` can't be stored exactly in IEEE 754 binary64 format, so what you end up with is something very slightly smaller.
>>> from decimal import Decimal
>>> Decimal(9.95)
Decimal('9.949999999999999289457264239899814128875732421875')
That's the reason that it rounds down.
Good practice is to create your Decimal instances from strings rather than floats.
>>> Decimal(9.95).quantize(Decimal('1.1'),ROUND_HALF_UP)
Decimal('9.9')
>>> Decimal('9.95').quantize(Decimal('1.1'),ROUND_HALF_UP)
Decimal('10.0') |
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Date |
User |
Action |
Args |
2018-02-22 10:12:18 | mark.dickinson | set | recipients:
+ mark.dickinson, felix.engelmann |
2018-02-22 10:12:18 | mark.dickinson | set | messageid: <1519294338.56.0.467229070634.issue32908@psf.upfronthosting.co.za> |
2018-02-22 10:12:18 | mark.dickinson | link | issue32908 messages |
2018-02-22 10:12:18 | mark.dickinson | create | |
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