70 lines
2.4 KiB
Swift
70 lines
2.4 KiB
Swift
// Copyright © 2014-2019 the Surge contributors
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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import XCTest
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@testable import Surge
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// swiftlint:disable nesting
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class RandomTests: XCTestCase {
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// MARK: - Box-Muller Transform
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func test_box_muller_transform_float() {
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typealias Scalar = Float
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let lhs: [Scalar] = .randomNormalized()
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let rhs: [Scalar] = .randomNormalized()
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let actual: [Scalar] = { lhs, rhs in
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var (lhs, rhs) = (lhs, rhs)
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boxMullerTransformInPlace(&lhs, &rhs)
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return lhs
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}(lhs, rhs)
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let expected: [Scalar] = zip(lhs, rhs).map { args in
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let (lhs, rhs) = args
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return sqrt(-2.0 * log(lhs)) * cos(2.0 * .pi * rhs)
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}
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XCTAssertEqual(actual, expected, accuracy: 1e-4)
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}
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func test_box_muller_transform_double() {
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typealias Scalar = Double
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let lhs: [Scalar] = .randomNormalized()
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let rhs: [Scalar] = .randomNormalized()
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let actual: [Scalar] = { lhs, rhs in
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var (lhs, rhs) = (lhs, rhs)
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boxMullerTransformInPlace(&lhs, &rhs)
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return lhs
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}(lhs, rhs)
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let expected: [Scalar] = zip(lhs, rhs).map { args in
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let (lhs, rhs) = args
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return sqrt(-2.0 * log(lhs)) * cos(2.0 * .pi * rhs)
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}
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XCTAssertEqual(actual, expected, accuracy: 1e-4)
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}
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}
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