English | 日本語

PhysicalUnits

A Swift library for type-safe physical units. Unit consistency is verified at compile time with minimal runtime overhead.

Features

• Type-safe unit conversion: Compile-time validation of conversions between different units
• Physics formula operators: Natural syntax for formulas like F = m * a, E = F * d, P = V * I
• SI prefix support: Automatic nano-to-tera coverage via the MetricUnit<BaseUnit> pattern
• High performance: Optimized with @frozen and @inlinable
• Multi-platform: iOS, macOS, watchOS, tvOS, visionOS

Installation

Swift Package Manager

dependencies: [
    .package(url: "https://github.com/no-problem-dev/swift-physical-units.git", from: "1.0.0")
]

Usage

Basic Unit Conversion

import PhysicalUnits

// Length
let distance = Length(100, unit: .meters)
print(distance.kilometers)  // 0.1

// Mass
let mass = Mass(1, unit: .kilograms)
print(mass.grams)  // 1000.0

// Time
let time = Duration(1, unit: .hours)
print(time.seconds)  // 3600.0

Physics Formula Calculations

// Speed = Distance / Time
let distance = Length(100, unit: .kilometers)
let time = Duration(2, unit: .hours)
let speed: Speed = distance / time
print(speed.kilometersPerHour)  // 50.0

// Force = Mass × Acceleration
let mass = Mass(10, unit: .kilograms)
let acceleration = Acceleration(9.8, unit: .metersPerSecondSquared)
let force: Force = mass * acceleration
print(force.newtons)  // 98.0

// Power = Voltage × Current
let voltage = Voltage(100, unit: .volts)
let current = Current(5, unit: .amperes)
let power: Power = voltage * current
print(power.watts)  // 500.0

Ohm's Law

// V = IR
let current = Current(2, unit: .amperes)
let resistance = Resistance(50, unit: .ohms)
let voltage: Voltage = current * resistance
print(voltage.volts)  // 100.0

// I = V/R
let current2: Current = voltage / resistance
print(current2.amperes)  // 2.0

Rotational Motion

// Angular speed
let angle = Angle(360, unit: .degrees)
let time = Duration(1, unit: .seconds)
let angularSpeed: AngularSpeed = angle / time
print(angularSpeed.rpm)  // 60.0

// Linear speed = angular speed × radius
let radius = Length(0.5, unit: .meters)
let linearSpeed: Speed = angularSpeed * radius
print(linearSpeed.metersPerSecond)  // 3.14...

Battery Capacity

// Charge
let battery = Charge(milliampereHours: 5000)
print(battery.ampereHours)  // 5.0
print(battery.coulombs)  // 18000.0

// Discharge time
let current = Current(500, unit: .milliamperes)
let dischargeTime: Duration = battery / current
print(dischargeTime.hours)  // 10.0

Supported Dimensions

Base Dimensions

Derived Dimensions

Architecture

PhysicalUnits/
├── Core/
│   ├── Measurement.swift      # Generic measurement type
│   ├── Unit.swift             # Unit protocol
│   └── MetricUnit.swift       # SI prefix support
├── Dimensions/
│   ├── Length/                # Length
│   ├── Mass/                  # Mass
│   ├── Time/                  # Time
│   ├── Speed/                 # Speed
│   ├── Acceleration/          # Acceleration
│   ├── Force/                 # Force
│   ├── Energy/                # Energy
│   ├── Power/                 # Power
│   ├── Voltage/               # Voltage
│   ├── Current/               # Current
│   ├── Resistance/            # Resistance
│   ├── Charge/                # Charge
│   ├── Angle/                 # Angle
│   ├── AngularSpeed/          # Angular speed
│   ├── Frequency/             # Frequency
│   └── ...
└── Formulas/
    ├── KinematicsOperators.swift   # Kinematics
    ├── MechanicsOperators.swift    # Mechanics
    ├── ElectricityOperators.swift  # Electricity
    └── FrequencyOperators.swift    # Frequency & angular speed

License

MIT License — see LICENSE for details.