Added LCM & GCM functions

Author: 65001

AbMath/Utilities/Reverse Polish Notation/Math/DoFunctions.cs

@@ -52,14 +52,26 @@ public static double Min(params double[] Arguments)
                 return Arguments[1];
             }
 
+            public static double Lcm(params double[] Arguments)
+            {
+                return (Arguments[0] * Arguments[1]) / Gcd(Arguments);
+            }
+
+            public static double Gcd(params double[] Arguments)
+            {
+                Arguments[0] = Math.Abs(Arguments[0]);
+                Arguments[1] = Math.Abs(Arguments[1]);
+                return (Arguments[1] == 0) ? Arguments[0] : Gcd(Arguments[1], Arguments[0] % Arguments[1]);
+            }
+
             public static double ln(params double[] Arguments)
             {
                 return Math.Log(Arguments[0]);
             }
 
             public static double Log(params double[] Arguments)
             {
-                if (Arguments.Length == 0)
+                if (Arguments.Length == 1)
                 {
                     return Math.Log(Arguments[0]);
                 }

AbMath/Utilities/Reverse Polish Notation/Reverse Polish Notation.cs

@@ -9,6 +9,21 @@ namespace AbMath.Utilities
     /// Reverse Polish Notation
     /// Used for math equations
     /// </summary>
+    /// 
+    
+    //TODO
+    //ABS
+    //ARCSIN,ARCTAN,ARCCOS
+    //Random
+    //Random(Min,Max)
+    //Generify
+    //Auto Scaling from decimal to double to Big Integer
+    //Complex Number Support sqrt(-1) = i
+
+    //TODO
+    //Add a data class so that other classes such as
+    //the Tokenizer, Shunter, and the like don't need a copy of RPN.
+
     public partial class RPN
     {
         public enum Assoc { Left, Right };

AbMath/Utilities/Reverse Polish Notation/Shunt.cs

@@ -19,6 +19,10 @@ public class Shunt : IShunt<string>
             Queue<string> Output;
             Stack<string> Operator;
 
+            //TODO: Implement Variadic Functions
+            //See http://wcipeg.com/wiki/Shunting_yard_algorithm#Variadic_functions
+            Stack<int> Arity;
+
             public Shunt(RPN rpn)
             {
                 RPN = rpn;

AbMath/Utilities/Reverse Polish Notation/Startup/Default Functions.cs

@@ -50,6 +50,18 @@ private void DefaultFunctions()
                 Compute = new Run(DoFunctions.Round)
             });
 
+            AddFunction("gcd", new Functions
+            {
+                Arguments = 2,
+                Compute = new Run(DoFunctions.Gcd)
+            });
+
+            AddFunction("lcm", new Functions
+            {
+                Arguments = 2,
+                Compute = new Run(DoFunctions.Lcm)
+            });
+
             AddFunction("ln", new Functions
             {
                 Arguments = 1,