Integral optimized

Author: WhiteBlackGoose

AngouriMath/Functions/Algebra/Integration.cs

@@ -10,9 +10,6 @@ public abstract partial class Entity
         /// <summary>
         /// Returns a value of a definite integral of a function. Only works for one-variable functions
         /// </summary>
-        /// <param name="func">
-        /// Function with only one variable
-        /// </param>
         /// <param name="x">
         /// Variable to integrate over
         /// </param>
@@ -23,17 +20,14 @@ public abstract partial class Entity
         /// The up bound for integrating
         /// </param>
         /// <returns></returns>
-        public Number DefiniteIntegral(Entity func, VariableEntity x, Number from, Number to)
+        public Number DefiniteIntegral(VariableEntity x, Number from, Number to)
         {
-            return Integration.Integrate(func, x, from, to, 100);
+            return Integration.Integrate(this, x, from, to, 100);
         }
 
         /// <summary>
         /// Returns a value of a definite integral of a function. Only works for one-variable functions
         /// </summary>
-        /// <param name="func">
-        /// Function with only one variable
-        /// </param>
         /// <param name="x">
         /// Variable to integrate over
         /// </param>
@@ -47,9 +41,9 @@ public Number DefiniteIntegral(Entity func, VariableEntity x, Number from, Numbe
         /// Accuracy (initially, amount of iterations)
         /// </param>
         /// <returns></returns>
-        public Number DefiniteIntegral(Entity func, VariableEntity x, Number from, Number to, int stepCount)
+        public Number DefiniteIntegral(VariableEntity x, Number from, Number to, int stepCount)
         {
-            return Integration.Integrate(func, x, from, to, stepCount);
+            return Integration.Integrate(this, x, from, to, stepCount);
         }
     }
     public static class Integration
@@ -61,11 +55,12 @@ public static Number Integrate(Entity func, VariableEntity x, Number from, Numbe
             double ReTo = to.Re;
             double ImTo = to.Im;
             var res = new Number(0, 0);
+            var cfunc = func.Compile(x.Name);
             for(int i = 0; i <= stepCount; i++)
             {
                 var share = ((double)i) / stepCount;
                 var tmp = new Number(ReFrom * share + ReTo * (1 - share), ImFrom * share + ImTo * (1 - share));
-                res += func.Substitute(x, tmp).Eval().GetValue();
+                res += cfunc.Eval(tmp);
             }
             return res / (stepCount + 1) * (to - from);
         }

Samples/Program.cs

@@ -10,23 +10,17 @@ class Program
         static void Main(string[] args)
         {
             var x = MathS.Var("x");
-            
-            var expr = (x * MathS.Cos(x) / MathS.Sin(MathS.Sqrt(x / MathS.Ln(x)))
-            * x * MathS.Cos(x) / MathS.Sin(MathS.Sqrt(x / MathS.Ln(x)))
-                * x * MathS.Cos(x) / MathS.Sin(MathS.Sqrt(x / MathS.Ln(x)))
-                    * x * MathS.Cos(x) / MathS.Sin(MathS.Sqrt(x / MathS.Ln(x))));//*/
-            //var expr = MathS.Sqr(x - 4) + MathS.Log(3, MathS.Sin(x));
-            var func = expr.Compile("x");
+            var y = MathS.Var("y");
 
-            var iter = 10000000;
+            var expr = MathS.Sin(x) * MathS.Sqrt(x + MathS.Cos(x)) / 3;
+            //Console.WriteLine(func.Eval(1, 2));
+            //return;
+
+            var iter = 1000;
             var stopWatch = new Stopwatch();
             stopWatch.Start();
-            var a = 0.0;
-            var cont = 3;
             for (int i = 0; i < iter; i++)
-                func.Eval(3);
-                //expr.Substitute(x, 3).Eval();
-                //a = Math.Sqrt(cont - 4) + Math.Log(cont, Math.Sin(cont));
+                expr.DefiniteIntegral(x, 1, 10);
             stopWatch.Stop();
             Console.Write(((double)stopWatch.ElapsedMilliseconds) / iter * 1000000);
             Console.WriteLine(" ns");