PlaygroundCalculatorSupport

Turn your Swift Playground into an interactive calculator, with units and vector support.

Features

• Based on Foundation's highly extensible unit system
• Integrate units into calculations in a quick and concise way
• Easy-to-use vector support (also with units)
• Use LANumerics to solve linear equations

Installation

PlaygroundCalculatorSupport is available as a Swift Package. However, currently there's no built-in way to integrate a Swift Package into a Swift Playground inside Xcode. It is recommended to use Arena to do so.

arena -n "PlaygroundCalculator" Cay-Zhang/PlaygroundCalculatorSupport@branch:master

Basic Support

Under Module PlaygroundCalculatorSupport.

Calculation with Units

3.0.cm + 4.m  // 4.03 m
3.cm / 4.cm  // 0.75
3.0 * 4.m³  // 12.0 m³

3.m * 24.degrees  // Error

12.0.cm.converted(to: .meters)  // 0.12 m
30.0.degrees.converted(to: .revolutions)  // 0.08333 rev

// Length -> Area -> Volume
let a = 8.7.cm, b = 7.3.cm
let A_rectangle = a * b  // 0.00635 m²
A_rectangle.converted(to: .squareInches)  // 9.84407 in²
let V_cuboid = A_rectangle * 7.m  // 0.04446 m³

Vectors

// Cartesian Coordinates <x, y>
let vec_a = 3.0.cm ++ 4.0.cm  // <3.0 cm, 4.0 cm>
vec_a.magnitude  // 5.0 cm
vec_a.angle  // 53.1301 °

// Polar Coordinates <r, θ>
let vec_b = sqrt(2).m ++ 135.0.degrees  // <-1.0 m, 1.0 m>

// Dot Product
vec_a * vec_b  // 0.01 m

Linear Algebra (LANumerics)

// Example of solving an electric circuit problem involving a system of linear equations
import PlaygroundCalculatorSupport
import Electricity
import LANumerics

let Va = 15.V, Ra = 18.Ω
let Vb = 12.V, Rb = 19.Ω
let Vc = 36.V, Rc = 12.Ω

let Ia_Ib_Ic = Matrix.withBaseValue([
    [1.Ω, 1.Ω, 1.Ω],
    [Ra , -Rb, 0.Ω],
    [Ra , 0.Ω, -Rc]
]).solve(withBaseValue:
    [0.V, Va - Vb, Va - Vc]
)  // [-0.46183, -0.59542, 1.05725]

let Ia = Ia_Ib_Ic[0].A  // -0.46183 A

Electricity

Under Module Electricity.

Global Constants

• Vacuum Permittivity 𝝴
• Coulomb Constant k

Units

Dimension	Base Unit
UnitElectricCharge	coulombs (C)
UnitElectricResistance	ohms (Ω)
UnitElectricPotentialDifference	volts (V)
UnitElectricCurrent	amperes (A)
UnitCapacitance	farads (F)
UnitElectricField	newtonsPerCoulomb (NpC)
UnitElectricFlux	newtonSquareMetersPerCoulomb

Utilities

Circuits Solving

// Find V1
let V = 12.V
let R1 = 13.Ω
let R2 = 22.Ω
let R3 = 16.Ω
let R4 = 18.Ω
let R5 = 28.Ω
let R6 = 13.Ω

let R14 = resistance(series: R1, R4)  // 31.0 Ω
let R124 = resistance(parallel: R14, R2)  // 12.86792 Ω

let V14 = R124 / (R124 + R6) * V  // 5.96937 V
let V1 = R1 / (R1 + R4) * V14  // 2.50328 V