Cookbooks
Swift
Chapter 3. Numbers
Working with complex numbers

Swift:
Working with complex numbers

How to:

Swift doesn’t have built-in complex number support, but we can roll our own:

struct ComplexNumber {
    var real: Double
    var imaginary: Double
    
    func add(_ other: ComplexNumber) -> ComplexNumber {
        return ComplexNumber(real: real + other.real, imaginary: imaginary + other.imaginary)
    }
    
    // Additional methods like subtraction, multiplication, etc.
}

let first = ComplexNumber(real: 2, imaginary: 3)
let second = ComplexNumber(real: 1, imaginary: 4)
let result = first.add(second)
print("Result: \(result.real) + \(result.imaginary)i")
// Sample Output: Result: 3.0 + 7.0i

Deep Dive

Complex numbers popped up in the 16th century in algebraic equations. They’re essential in quantum mechanics, control theory, and many other fields. Apple’s Swift doesn’t have a standard library for complex numbers, unlike languages like Python or C++. Alternatives to rolling your own include using Numerics package which includes complex numbers support or wrapping C++ complex library with Swift’s interoperability.

See Also

Rounding numbers