Unit Computation with Pint

Cognitive prosthetics for unit-aware computation. Use Pint for converting between units, performing unit arithmetic, checking dimensional compatibility, and simplifying compound units.

When to Use

• Converting between units (meters to feet, kg to pounds)

• Unit-aware arithmetic (velocity x time = distance)

• Dimensional analysis (is force = mass x acceleration?)

• Simplifying compound units to base or named units

• Parsing and analyzing quantities with units

Quick Reference

I want to... Command Example

Convert units convert

convert "5 meters" --to feet

Unit math calc

calc "10 m/s * 5 s"

Check dimensions check

check newton --against "kg * m / s^2"

Parse quantity parse

parse "100 km/h"

Simplify units simplify

simplify "1 kg*m/s^2"

Commands

parse

Parse a quantity string into magnitude, units, and dimensionality.

uv run python -m runtime.harness scripts/pint_compute.py
parse "100 km/h"

uv run python -m runtime.harness scripts/pint_compute.py
parse "9.8 m/s^2"

convert

Convert a quantity to different units.

uv run python -m runtime.harness scripts/pint_compute.py
convert "5 meters" --to feet

uv run python -m runtime.harness scripts/pint_compute.py
convert "100 km/h" --to mph

uv run python -m runtime.harness scripts/pint_compute.py
convert "1 atmosphere" --to pascal

calc

Perform unit-aware arithmetic. Operators must be space-separated.

uv run python -m runtime.harness scripts/pint_compute.py
calc "5 m * 3 s"

uv run python -m runtime.harness scripts/pint_compute.py
calc "10 m / 2 s"

uv run python -m runtime.harness scripts/pint_compute.py
calc "5 meters + 300 cm"

check

Check if two units have compatible dimensions.

uv run python -m runtime.harness scripts/pint_compute.py
check newton --against "kg * m / s^2"

uv run python -m runtime.harness scripts/pint_compute.py
check joule --against "kg * m^2 / s^2"

simplify

Simplify compound units to base or compact form.

uv run python -m runtime.harness scripts/pint_compute.py
simplify "1 kg*m/s^2"

uv run python -m runtime.harness scripts/pint_compute.py
simplify "1000 m"

Common Unit Domains

Domain Examples

Length meter, foot, inch, mile, km, yard

Time second, minute, hour, day, year

Mass kg, gram, pound, ounce, ton

Velocity m/s, km/h, mph, knot

Energy joule, calorie, eV, kWh, BTU

Force newton, pound_force, dyne

Temperature kelvin, celsius, fahrenheit

Pressure pascal, bar, atmosphere, psi

Power watt, horsepower

Output Format

All commands return JSON with relevant fields:

{ "result": "16.4042 foot", "magnitude": 16.4042, "units": "foot", "dimensionality": "[length]", "latex": "16.4042\,\mathrm{ft}" }

Error Handling

Dimensionality errors are caught and reported:

This will error - incompatible dimensions

uv run python -m runtime.harness scripts/pint_compute.py
convert "5 meters" --to kg

Error: Cannot convert '[length]' to '[mass]'

Related Skills

• /math-mode - Full math orchestration (SymPy + Z3)

• /sympy-compute - Symbolic computation