performance_data.swift

let elementsCount = 10_000_000
let fahrenheit = Array(repeating: 0.0, count: elementsCount).map { _ -> Double in
    return Double.random(in: 32.0 ... 113.0)
}

var fahrenheits = [[Double]]()
for _ in 0 ..< totalElements {
    fahrenheits.append(Array(repeating: 0.0, count: 1).map { _ -> Double in
        return Double.random(in: 32.0 ... 113.0)
    })
}