Added `sq` & `sqInPlace` to ‘Arithmetic.swift’

Sources/Surge/Arithmetic/Arithmetic.swift

@@ -700,6 +700,36 @@ func powInPlace<X: UnsafeMutableMemoryAccessible>(_ lhs: inout X, _ rhs: Double)
     return powInPlace(&lhs, rhs)
 }
 
+//// MARK: - Square
+
+public func sq<L: UnsafeMemoryAccessible>(_ lhs: L) -> [Float] where L.Element == Float {
+    var results = Array(lhs)
+    sqInPlace(&results)
+    return results
+}
+
+public func sq<L: UnsafeMemoryAccessible>(_ lhs: L) -> [Double] where L.Element == Double {
+    var results = Array(lhs)
+    sqInPlace(&results)
+    return results
+}
+
+// MARK: - Square: In Place
+
+func sqInPlace<L: UnsafeMutableMemoryAccessible>(_ lhs: inout L) where L.Element == Float {
+    let elementCount: vDSP_Length = numericCast(lhs.count)
+    withUnsafeMutableMemory(&lhs) { lm in
+        vDSP_vsq(lm.pointer, numericCast(lm.stride), lm.pointer, numericCast(lm.stride), elementCount)
+    }
+}
+
+public func sqInPlace<L: UnsafeMutableMemoryAccessible>(_ lhs: inout L) where L.Element == Double {
+    let elementCount: vDSP_Length = numericCast(lhs.count)
+    withUnsafeMutableMemory(&lhs) { lm in
+        vDSP_vsqD(lm.pointer, numericCast(lm.stride), lm.pointer, numericCast(lm.stride), elementCount)
+    }
+}
+
 // MARK: - Square Root
 
 /// Elemen-wise square root.

Tests/SurgeTests/ArithmeticTests.swift

@@ -529,6 +529,38 @@ class ArithmeticTests: XCTestCase {
         XCTAssertEqual(actual, expected, accuracy: 1e-8)
     }
 
+    // MARK: - Square
+
+    func test_sq_array_float() {
+        typealias Scalar = Float
+
+        let lhs: [Scalar] = (1...n).map { Scalar($0) / Scalar(n) }
+
+        var actual: [Scalar] = []
+        measure {
+            actual = Surge.sq(lhs)
+        }
+
+        let expected = lhs.map { pow($0, 2.0) }
+
+        XCTAssertEqual(actual, expected, accuracy: 1e-5)
+    }
+
+    func test_sq_array_double() {
+        typealias Scalar = Double
+
+        let lhs: [Scalar] = (1...n).map { Scalar($0) / Scalar(n) }
+
+        var actual: [Scalar] = []
+        measure {
+            actual = Surge.sq(lhs)
+        }
+
+        let expected = lhs.map { pow($0, 2.0) }
+
+        XCTAssertEqual(actual, expected, accuracy: 1e-8)
+    }
+
     // MARK: - Square Root
 
     func test_sqrt_array_array_float() {