September Morn Update

Task/Exponentiation-operator/BASIC/exponentiation-operator-2.basic

@@ -0,0 +1,23 @@
+      PRINT "11^5 = " ; FNipow(11, 5)
+      PRINT "PI^3 = " ; FNfpow(PI, 3)
+      END
+
+      DEF FNipow(A%, B%)
+      LOCAL I%, P%
+      P% = 1
+      FOR I% = 1 TO 32
+        P% *= P%
+        IF B% < 0 THEN P% *= A%
+        B% = B% << 1
+      NEXT
+      = P%
+
+      DEF FNfpow(A, B%)
+      LOCAL I%, P
+      P = 1
+      FOR I% = 1 TO 32
+        P *= P
+        IF B% < 0 THEN P *= A
+        B% = B% << 1
+      NEXT
+      = P

Task/Exponentiation-operator/BASIC/exponentiation-operator-3.basic

@@ -0,0 +1,6 @@
+100 DEF POW(X,Y)
+110   IF X=0 THEN LET POW=0:EXIT DEF
+120   LET POW=EXP(Y*LOG(X))
+130 END DEF
+140 PRINT POW(PI,3)
+150 PRINT PI^3

Task/Exponentiation-operator/Swift/exponentiation-operator.swift

@@ -0,0 +1,18 @@
+func raise<T: Numeric>(_ base: T, to exponent: Int) -> T {
+    precondition(exponent >= 0, "Exponent has to be nonnegative")
+    return Array(repeating: base, count: exponent).reduce(1, *)
+}
+
+infix operator **: MultiplicationPrecedence
+
+func **<T: Numeric>(lhs: T, rhs: Int) -> T {
+    return raise(lhs, to: rhs)
+}
+
+let someFloat: Float = 2
+let someInt: Int = 10
+
+assert(raise(someFloat, to: someInt) == 1024)
+assert(someFloat ** someInt == 1024)
+assert(raise(someInt, to: someInt) == 10000000000)
+assert(someInt ** someInt == 10000000000)

Task/Exponentiation-operator/VBA/exponentiation-operator.vba

@@ -0,0 +1,48 @@
+Public Function exp(ByVal base As Variant, ByVal exponent As Long) As Variant
+    Dim result As Variant
+    If TypeName(base) = "Integer" Or TypeName(base) = "Long" Then
+        'integer exponentiation
+        result = 1
+        If exponent < 0 Then
+            result = IIf(Abs(base) <> 1, CVErr(2019), IIf(exponent Mod 2 = -1, base, 1))
+        End If
+        Do While exponent > 0
+            If exponent Mod 2 = 1 Then result = result * base
+            base = base * base
+            exponent = exponent \ 2
+        Loop
+    Else
+        Debug.Assert IsNumeric(base)
+        'float exponentiation
+        If base = 0 Then
+            If exponent < 0 Then result = CVErr(11)
+        Else
+            If exponent < 0 Then
+                base = 1# / base
+                exponent = -exponent
+            End If
+            result = 1
+            Do While exponent > 0
+                If exponent Mod 2 = 1 Then result = result * base
+                base = base * base
+                exponent = exponent \ 2
+            Loop
+        End If
+    End If
+    exp = result
+End Function
+Public Sub main()
+    Debug.Print "Integer exponentiation"
+    Debug.Print "10^7=", exp(10, 7)
+    Debug.Print "10^4=", exp(10, 4)
+    Debug.Print "(-3)^3=", exp(-3, 3)
+    Debug.Print "(-1)^(-5)=", exp(-1, -5)
+    Debug.Print "10^(-1)=", exp(10, -1)
+    Debug.Print "0^2=", exp(0, 2)
+    Debug.Print "Float exponentiation"
+    Debug.Print "10.0^(-3)=", exp(10#, -3)
+    Debug.Print "10.0^(-4)=", exp(10#, -4)
+    Debug.Print "(-3.0)^(-5)=", exp(-3#, -5)
+    Debug.Print "(-3.0)^(-4)=", exp(-3#, -4)
+    Debug.Print "0.0^(-4)=", exp(0#, -4)
+End Sub