         }
     }
     
-    func testCos() {
+    func testCosNormal() {
         do {
             let elements: [Float] = [0, 0.5, 1, 1.5]
             let a = NDArray(shape: [2, 2], elements: elements)

            ("testLog", testLog),
            ("testSin", testSin),
            ("testCos", testCos),
            ("testTan", testTan)
        ]
    }
    

        }
    }
    
    func testTanNormal() {
        do {
            let elements: [Float] = [0, 0.5, 1, 1.5]
            let a = NDArray(shape: [2, 2], elements: elements)
