quantia

Unit-aware arithmetic with Monte Carlo uncertainty propagation.

Pure Python. No dependencies beyond the standard library.

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quantia lets you write calculations the way engineers think — with units attached to every value, and uncertainty tracked automatically.

import quantia as qu

# Exact calculations
d = qu.Q(100.0, 'm')
t = qu.Q(9.81,  's')
v = d / t
v.to('km/h')   # UnitFloat(36.69..., 'km/h')

# Temperature — affine conversion handled automatically
qu.Q(100.0, '°C').to('K')   # UnitFloat(373.15, 'K')

# Gauge to absolute pressure
qu.Q(500.0, 'psig').to('psia')  # UnitFloat(514.69..., 'psia')

# Uncertainty propagation
with qu.config(n_samples=5000, seed=42):
    Bo  = qu.ProbUnitFloat.normal(1.25, 0.05, 'm3_res')
    phi = qu.ProbUnitFloat.triangular(0.12, 0.18, 0.25, '1')

Vp   = qu.Q(1_000_000.0, 'm3_res')
ooip = Vp * phi * (1 - 0.25) / (Bo / qu.Q(1.0, 'm3_sc'))
lo, hi = ooip.interval(0.80)   # P10–P90

See Getting Started to install, or jump to the Five-Minute Tutorial.