Units

Physical units for dimensional analysis.

Usage

from dimtensor import units

# Access units
units.m      # meter
units.kg     # kilogram
units.s      # second

# Create compound units
velocity = units.m / units.s
acceleration = units.m / units.s**2
force = units.kg * units.m / units.s**2  # Same as units.N

SI Base Units

Attribute	Symbol	Dimension
units.m	m	Length
units.kg	kg	Mass
units.s	s	Time
units.A	A	Electric current
units.K	K	Temperature
units.mol	mol	Amount of substance
units.cd	cd	Luminous intensity

SI Derived Units

Attribute	Symbol	Equivalent
units.N	N	kg*m/s^2
units.J	J	kg*m^2/s^2
units.W	W	kg*m^2/s^3
units.Pa	Pa	kg/(m*s^2)
units.Hz	Hz	1/s
units.C	C	A*s
units.V	V	kgm^2/(As^3)
units.F	F	A^2s^4/(kgm^2)
units.ohm	ohm	kgm^2/(A^2s^3)

Length Units

Attribute	Symbol	SI Value
units.m	m	1 m
units.km	km	1000 m
units.cm	cm	0.01 m
units.mm	mm	0.001 m
units.um	um	1e-6 m
units.nm	nm	1e-9 m
units.mile	mi	1609.344 m
units.ft	ft	0.3048 m
units.inch	in	0.0254 m

Time Units

Attribute	Symbol	SI Value
units.s	s	1 s
units.ms	ms	0.001 s
units.us	us	1e-6 s
units.ns	ns	1e-9 s
units.minute	min	60 s
units.hour	h	3600 s
units.day	d	86400 s

Energy Units

Attribute	Symbol	SI Value
units.J	J	1 J
units.kJ	kJ	1000 J
units.eV	eV	1.602e-19 J
units.cal	cal	4.184 J
units.kcal	kcal	4184 J

Pressure Units

Attribute	Symbol	SI Value
units.Pa	Pa	1 Pa
units.kPa	kPa	1000 Pa
units.bar	bar	1e5 Pa
units.atm	atm	101325 Pa

Angle Units

Attribute	Symbol	Note
units.rad	rad	Dimensionless
units.deg	deg	pi/180 rad

API Reference

Unit dataclass

Represents a physical unit.

A unit combines a dimension with a scale factor. The scale factor represents how many SI base units equal one of this unit.

Examples:

>>> meter = Unit("m", Dimension(length=1), 1.0)
>>> kilometer = Unit("km", Dimension(length=1), 1000.0)
>>> # 1 km = 1000 m, so scale = 1000

symbol: str instance-attribute

dimension: Dimension instance-attribute

scale: float instance-attribute

Dimension dataclass

Represents the physical dimension of a quantity.

A dimension is represented as a tuple of rational exponents for each of the 7 SI base dimensions. For example: - Velocity has dimension L¹T⁻¹ (length=1, time=-1) - Force has dimension M¹L¹T⁻² (mass=1, length=1, time=-2)

Dimensions support algebraic operations: - Multiplication: adds exponents - Division: subtracts exponents - Power: multiplies exponents by the power

length: Fraction property

Exponent of length dimension.

mass: Fraction property

Exponent of mass dimension.

time: Fraction property

Exponent of time dimension.

current: Fraction property

Exponent of electric current dimension.

temperature: Fraction property

Exponent of temperature dimension.

amount: Fraction property

Exponent of amount of substance dimension.

luminosity: Fraction property

Exponent of luminous intensity dimension.