🔒 Pint quirk with units in ratio

[orchid basin]

First of all... is there a way to make pint use decimal.Decimal to avoid floating point errors, second of all, why does this: ```py
from pint import UnitRegistry

ureg = UnitRegistry(auto_reduce_dimensions=True)
Q_ = ureg.Quantity

def Dosage(bodyweight, doseperweight, dosepervolume):
bw = Q_(bodyweight)
dpw = Q_(doseperweight)
dpv = Q_(dosepervolume)

return (bw*dpw)/dpv

print("input all quantities with units")
print(Dosage(
input("Bodyweight: "),
input("Dose per weight: "),
input("Dose per volume: ")
))
``` correctly produce 7.5 millileter for the inputs: 20kg, 150mcg/kg and 0.4mg/ml, but incorrectly produce 7.5 / millileter when the dose per volume is input at 2mg/5ml (equivalent)

[round oyster]

@orchid basin

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[orchid basin]

context (before you think im doing something dodgy 😂):

[noble nest]

https://github.com/hgrecco/pint/blob/master/pint/registry.py#L128

[round oyster]

pint/registry.py line 128

non_int_type=float,```

[noble nest]

You probably want to define that as Decimal, it could work, but I'm not sure

[orchid basin]

ah okay, cool, any ideas about the other part?

[noble nest]

Hmmm. There's likely some weird parsing going on. Could you try parsing that value as individuals like this?
dpv = Q_("2 mg") / Q_("5 ml")

You could split the input and apply the Q_ to both

If that doesn't work, I'm out of ideas, never used pint before

[orchid basin]

i mean, ideally i could yeah, but i want it to work on user input

and in the screenshot i posted, the reel that comment is on gave it exactly as "2mg/5ml" so i guess that thats just how they write it naturally

[noble nest]

Split the 2mg/5ml using .split method

[orchid basin]

oh true, yeah, cheers

cause its always gunna be a divide for a concentration, yeh

[noble nest]

!e ```py
foo = "2mg/5ml"
print(foo.split("/"))

[round oyster]

:white_check_mark: Your 3.14 eval job has completed with return code 0.

['2mg', '5ml']

[orchid basin]

yeah, i was overthinking it lmao

[noble nest]

Ye that happens, talking the problem out often solves it 😄

[orchid basin]

.close

[quartz elbow]

Did you mean:

[orchid basin]

!close

[round oyster]

Python help channel closed with !close

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