PiActor.swift

import Foundation

// Test impact of high-CPU actor on Swift app performance
// Task { let piActor = piActor; await piActor.calculatePI() }
// Code from https://alexwulff.medium.com/calculating-pi-with-swift-ed36730405ed
actor PiActor {
    func calculatePI() async {
        while(true) {
            var GregoryLeibniz : Double = 0
            var counter = 1
            while GregoryLeibniz * 4 != 3.1415 {
                var oddNumber = 2*counter - 1
                if counter % 2 == 0 {
                    GregoryLeibniz -= 1/Double(oddNumber)
                }
                else {
                    GregoryLeibniz += 1/Double(oddNumber)
                }
                print(GregoryLeibniz*4)
                counter += 1
            }

            print(counter)

            // insert suspension point
            do {
                try await Task.sleep(nanoseconds: 1000*1000)
            } catch {
                print("error sleeping: \(error)")
                return
            }
        }
    }
}