Changeset 6687 for trunk/sources/HeuristicLab.Optimization/3.3/Calculator.cs

Timestamp:

08/31/11 17:42:00 (13 years ago)

Author:

epitzer

Message:

Extend calculator to support other data types, literals, stack manipulations and conditionals (#1622)

File:

• trunk/sources/HeuristicLab.Optimization/3.3/Calculator.cs (modified) (5 diffs)

trunk/sources/HeuristicLab.Optimization/3.3/Calculator.cs

@@ -1 +1 @@
 using System;
 using System.Collections.Generic;
-using System.Drawing;
 using System.Linq;
 using System.Text.RegularExpressions;
@@ -7 +6 @@
 using HeuristicLab.Core;
 using HeuristicLab.Data;
-using HeuristicLab.Parameters;
 using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
 using System.Globalization;
 
-namespace HeuristicLab.Optimization {  
-    
+namespace HeuristicLab.Optimization {
+
   [StorableClass]
   public class Calculator : IDeepCloneable {
 
     #region Fields & Properties
-    
+
     private List<string> tokens;
 
@@ -26 +24 @@
     }
 
-    private static readonly Regex TokenRegex = new Regex(@"[a-zA-Z0-9._]+|""([^""]|\"")+""|[-+*/^]|log");    
+    private static readonly Regex TokenRegex =
+      new Regex(@"[a-zA-Z0-9._]+|""([^""]|\\"")*""|'([^']|\\')*'|[-+*/<>^]|dup|swap|drop|log|true|false|if|==|not|isnull|null|ismatch|rename");
 
     #endregion
@@ -35 +34 @@
     protected Calculator(bool deserializing) { }
     public Calculator() { }
-    public Calculator(Calculator original, Cloner cloner) {
-      this.tokens = original.tokens.ToList();
+    protected Calculator(Calculator original, Cloner cloner) {
+      cloner.RegisterClonedObject(original, this);
+      tokens = original.tokens.ToList();
     }
     public IDeepCloneable Clone(Cloner cloner) {
@@ -46 +46 @@
     #endregion
 
-    public IEnumerable<string> Tokenize(string s) {
+    private static IEnumerable<string> Tokenize(string s) {
       return TokenRegex.Matches(s).Cast<Match>().Select(m => m.Value);
     }
 
-    private double GetVariableValue(IDictionary<string, IItem> variables, string name) {
-      if (variables.ContainsKey(name)) {
-        var item = variables[name];
-        var intValue = item as IntValue;
-        if (intValue != null) {
-          return intValue.Value;
-        } else {
-          var doubleValue = item as DoubleValue;
-          if (doubleValue != null)
-            return doubleValue.Value;
-          else
-            throw new InvalidOperationException("Non numerical argument");
-        }
-      } else {
-        throw new InvalidOperationException(string.Format("variable \"{0}\" not found", name));
-      }
-    }
-
     public IItem GetValue(IDictionary<string, IItem> variables) {
-      var stack = new Stack<double>();
-      Action<Func<double, double, double>> binf = op => {
-        var b = stack.Pop();
-        stack.Push(op(stack.Pop(), b));
-      };
-      try {
-        foreach (var token in tokens) {
+      var stack = new Stack<object>();
+      int i = 0;
+      try {
+        for (; i<tokens.Count; i++) {
+          var token = tokens[i];
           double d;
-          if (double.TryParse(token,
-                NumberStyles.AllowDecimalPoint |
-              NumberStyles.AllowExponent |
-              NumberStyles.AllowLeadingSign, CultureInfo.InvariantCulture, out d)) {
+          if (TryParse(token, out d)) {
             stack.Push(d);
           } else if (token.StartsWith("\"")) {
             stack.Push(GetVariableValue(variables, token.Substring(1, token.Length - 2).Replace(@"\""", @"""")));
+          } else if (token.StartsWith("'")) {
+            stack.Push(token.Substring(1, token.Length-2).Replace("\'", "'"));
           } else {
-            switch (token) {
-              case "log": stack.Push(Math.Log(stack.Pop())); break;
-              case "+": binf((x, y) => x + y); break;
-              case "-": binf((x, y) => x - y); break;
-              case "*": binf((x, y) => x * y); break;
-              case "/": binf((x, y) => x / y); break;
-              case "^": binf(Math.Pow); break;
-              default: stack.Push(GetVariableValue(variables, token)); break;
-            }
+            Apply(token, stack, variables);
           }
         }
-      } catch (InvalidOperationException x) {
-        return new StringValue(string.Format("Calculation Failed: {0}", x.Message));
-      }
-      if (stack.Count != 1)
-        return new StringValue("Invalid final evaluation stack size != 1");
-      return new DoubleValue(stack.Pop());      
-    }    
+      } catch (Exception x) {
+        throw new Exception(string.Format(
+          "Calculation Failed at token #{1}: '{2}' {0}current stack is: {0}{3}", Environment.NewLine,
+          i, tokens[i], string.Join(Environment.NewLine, stack.Select(AsString))),
+          x);
+      }
+      if (stack.Count != 1) throw new Exception(string.Format("Invalid final evaluation stack size {0} (should be 1)", stack.Count));
+      var result = stack.Pop();
+      if (result is string) return new StringValue((string)result);
+      if (result is double) return new DoubleValue((double)result);
+      if (result is bool) return new BoolValue((bool)result);
+      return null;
+    }
+
+    private static void Apply(string token, Stack<object> stack, IDictionary<string, IItem> variables) {
+      switch (token) {
+        case "null":  stack.Push(null); break;
+        case "true":  stack.Push(true); break;
+        case "false": stack.Push(false); break;
+
+        case "drop": stack.Pop(); break;
+        case "dup": stack.Push(stack.Peek()); break;
+        case "swap":
+          var top = stack.Pop();
+          var next = stack.Pop();
+          stack.Push(top);
+          stack.Push(next);
+          break;
+
+        case "log": Apply(stack, x => Math.Log((double)x)); break;
+        case "+": Apply(stack, (x, y) => (double)x + (double)y); break;
+        case "-": Apply(stack, (x, y) => (double)x - (double)y); break;
+        case "*": Apply(stack, (x, y) => (double)x * (double)y); break;
+        case "/": Apply(stack, (x, y) => (double)x / (double)y); break;
+        case "^": Apply(stack, (x, y) => Math.Pow((double)x, (double)y)); break;
+        case "<": Apply(stack, (x, y) => (double)x < (double)y); break;
+        case ">": Apply(stack, (x, y) => (double)x > (double)y); break;
+
+        case "==": Apply(stack, (x, y) => Equal(x, y)); break;
+        case "not": Apply(stack, x => !(bool)x); break;
+        case "isnull": Apply(stack, x => x == null); break;
+        case "if": Apply(stack, (then, else_, cond) => (bool)cond ? then : else_); break;
+
+        case "ismatch": Apply(stack, (s, p) => new Regex((string)p).IsMatch((string)s)); break;
+        case "rename": Apply(stack, (s, p, r) => new Regex((string)p).Replace((string)s, (string)r)); break;
+
+        default: stack.Push(GetVariableValue(variables, token)); break;
+      }
+    }
+
+    #region Auxiliary Functions
+
+    #region IItem value conversion
+    private static object GetIntValue(IItem value) {
+      var v = value as IntValue;
+      if (v != null) return (double)v.Value;
+      return null;
+    }
+
+    private static object GetDoubleValue(IItem value) {
+      var v = value as DoubleValue;
+      if (v != null) return v.Value;
+      return null;
+    }
+
+    private static object GetBoolValue(IItem value) {
+      var v = value as BoolValue;
+      if (v != null) return v.Value;
+      return null;
+    }
+
+    private static object GetVariableValue(IDictionary<string, IItem> variables, string name) {
+      if (variables.ContainsKey(name)) {
+        var item = variables[name];
+        return
+          GetIntValue(item) ??
+          GetDoubleValue(item) ??
+          GetBoolValue(item) ??
+          item.ToString();
+      }
+      return null;
+    }
+    #endregion
+
+    #region variadic equality
+    private static bool Equal(object a, object b) { return EqualNumber(a, b) || EqualBool(a, b) || EqualString(a, b) || a == b; }
+    private static bool EqualNumber(object a, object b) { return a is double && b is double && (double)a == (double)b; }
+    private static bool EqualBool(object a, object b) { return a is bool && b is bool && (bool)a == (bool)b; }
+    private static bool EqualString(object a, object b) { return a is string && b is string && ((string)a).Equals((string)b); }
+    #endregion
+
+    #region stack calculation
+    private static void Apply(Stack<object> stack, Func<object, object> func) {
+      if (stack.Count < 1)
+        throw new InvalidOperationException("Stack is empty");
+      var a = stack.Pop();
+      try {
+        stack.Push(func(a));
+      } catch (Exception) {
+        stack.Push(a);
+        throw;
+      }
+    }
+
+    private static void Apply(Stack<object> stack, Func<object, object, object> func) {
+      if (stack.Count < 2)
+        throw new InvalidOperationException("Stack contains less than two elements");
+      var b = stack.Pop();
+      var a = stack.Pop();
+      try {
+        stack.Push(func(a, b));
+      } catch (Exception) {
+        stack.Push(b);
+        stack.Push(a);
+        throw;
+      }
+    }
+
+    private static void Apply(Stack<object> stack, Func<object, object, object, object> func) {
+      if (stack.Count < 3)
+        throw new InvalidOperationException("Stack contains less than three elements");
+      var c = stack.Pop();
+      var b = stack.Pop();
+      var a = stack.Pop();
+      try {
+        stack.Push(func(a, b, c));
+      } catch (Exception) {
+        stack.Push(a);
+        stack.Push(b);
+        stack.Push(c);
+        throw;
+      }
+    }
+    #endregion
+
+    private static bool TryParse(string token, out double d) {
+      return double.TryParse(token,
+                             NumberStyles.AllowDecimalPoint |
+                             NumberStyles.AllowExponent |
+                             NumberStyles.AllowLeadingSign, CultureInfo.InvariantCulture, out d);
+    }
+
+    private static string AsString(object o) {
+      if (o == null) return "null";
+      if (o is string) return string.Format("'{0}'", o);
+      return o.ToString();
+    }
+
+    #endregion
   }
 }