Measurement converted(to:) is providing the wrong answer

Originator:jeffkempster
Number:rdar://38641535 Date Originated:3/19/2018
Status:Open Resolved:
Product:iOS Product Version:11
Classification:Bug Reproducible:Always
 
Area:
Foundation

Summary:
If you use the built in Measurement class and function to convert(to:) from miles to feet the result in not accurate.   In my example converting 1 mile to feet provides 5279.98687664042 ft

Steps to Reproduce:
import Foundation
let lengthMiles = Measurement(value: 1, unit: UnitLength.miles) // 1.0 mi
let lengthFeet = lengthMiles.converted(to: UnitLength.feet) // 5279.98687664042 ft

Expected Results:  Should return 5280.0 ft

Actual Results: Returns 5279.98687664042 ft

Version/Build:  Version 9.2 (9C40b). MacOS 10.13.3 (17D102)

Configuration:  2016 MacBook Pro 15"

Comments


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