[Quantproject-developers] QuantProject/b1_ADT/Statistics/Combinatorial Combination.cs, 1.1, 1.2

[Glauco S. <gla...@us...>]

Update of /cvsroot/quantproject/QuantProject/b1_ADT/Statistics/Combinatorial
In directory sc8-pr-cvs7.sourceforge.net:/tmp/cvs-serv10282/b1_ADT/Statistics/Combinatorial

Modified Files:
	Combination.cs 
Log Message:
The TotalNumberOfCombinations property has been added (to be read to know how many combinations will be generated)

Index: Combination.cs
===================================================================
RCS file: /cvsroot/quantproject/QuantProject/b1_ADT/Statistics/Combinatorial/Combination.cs,v
retrieving revision 1.1
retrieving revision 1.2
diff -C2 -d -r1.1 -r1.2
*** Combination.cs	21 Aug 2006 19:45:05 -0000	1.1
--- Combination.cs	8 Sep 2006 15:34:41 -0000	1.2
***************
*** 16,23 ****
--- 16,33 ----
  		private int length;
  		
+ 		/// <summary>
+ 		/// each combination length
+ 		/// </summary>
  		public int Length
  		{
  			get { return this.length; }
  		}
+ 		public long TotalNumberOfCombinations
+ 		{
+ 			get
+ 			{
+ 				return this.totalNumberOfCombinations();
+ 			}
+ 		}
  
  		/// <summary>
***************
*** 129,132 ****
--- 139,163 ----
  			return this.currentCombinationValues[ elementIndex ];
  		}
+ 		#region totalNumberOfCombinations
+ 		private long totalNumberOfCombinations_getNumerator()
+ 		{
+ 			int firstFactor = this.maxValue - this.minValue + 1;
+ 			long numerator = 1;
+ 			for ( int factor = firstFactor ; factor > firstFactor - this.length ;
+ 				factor -- )
+ 				numerator *= factor;
+ 			return numerator;
+ 		}
+ 		private long totalNumberOfCombinations_getDenominator()
+ 		{
+ 			return ExtendedMath.Factorial( this.length );
+ 		}
+ 		private long totalNumberOfCombinations()
+ 		{
+ 			long numerator = this.totalNumberOfCombinations_getNumerator();
+ 			long denominator = this.totalNumberOfCombinations_getDenominator();
+ 			return numerator / denominator;
+ 		}
+ 		#endregion
  	}
  }