[Quantproject-developers] QuantProject/b1_ADT/Statistics NormalDistribution.cs,1.3,1.4

[Marco M. <mi...@us...>]

Update of /cvsroot/quantproject/QuantProject/b1_ADT/Statistics
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv22873/b1_ADT/Statistics

Modified Files:
	NormalDistribution.cs 
Log Message:
Fixed bug in the constructor method for the normal distribution class (the standard deviation must be > 0; otherwise an exception is raised)
In addition, new exceptions are now raised in some methods of the class, for gaining more control on the code


Index: NormalDistribution.cs
===================================================================
RCS file: /cvsroot/quantproject/QuantProject/b1_ADT/Statistics/NormalDistribution.cs,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** NormalDistribution.cs	14 Apr 2005 18:28:24 -0000	1.3
--- NormalDistribution.cs	2 Jun 2005 18:11:37 -0000	1.4
***************
*** 43,47 ****
  	  public NormalDistribution(double average, double stdDeviation)
      {
!     	if(stdDeviation < 0)
      		throw new Exception("Standard deviation must be > 0!");
      	
--- 43,47 ----
  	  public NormalDistribution(double average, double stdDeviation)
      {
!     	if(stdDeviation <= 0)
      		throw new Exception("Standard deviation must be > 0!");
      	
***************
*** 60,64 ****
      public double GetProbabilityDensityValue(double x)
      {
!     	double y;
      	y = Math.Pow(Math.E,(-Math.Pow(x-this.average,2)
      	             /(2*this.stdDeviation*this.stdDeviation)))
--- 60,67 ----
      public double GetProbabilityDensityValue(double x)
      {
!     	if(Double.IsInfinity(x) || Double.IsNaN(x))
!     		throw new Exception("Density value of x is not computable!");
!     	
!     	double y = 0;
      	y = Math.Pow(Math.E,(-Math.Pow(x-this.average,2)
      	             /(2*this.stdDeviation*this.stdDeviation)))
***************
*** 74,78 ****
   		public double GetProbability(double y)
      {
!      	return this.GetProbability(-this.infinity, y);
      }
      
--- 77,83 ----
   		public double GetProbability(double y)
      {
!      	if(Double.IsInfinity(y) || Double.IsNaN(y))
!     		throw new Exception("Prob(Y<y) is not computable!");
!  			return this.GetProbability(-this.infinity, y);
      }
      
***************
*** 83,89 ****
   		public double GetProbability(double a, double b)
      {
!      	return 
       	CalculusApproximation.GetArea((IPdfDefiner)this,a,b,
!      	                           this.numOfIntervalsForPDFIntegralApproximation);
      }
      
--- 88,98 ----
   		public double GetProbability(double a, double b)
      {
!      	if( Double.IsInfinity(a) || Double.IsNaN(a) ||
!  			    Double.IsInfinity(b) || Double.IsNaN(b) )
!     				throw new Exception("Prob(a<Y<b) is not computable!");
!  			
!  			return
       	CalculusApproximation.GetArea((IPdfDefiner)this,a,b,
!      	                           		this.numOfIntervalsForPDFIntegralApproximation);
      }