/// <summary>
        ///		Initialize the background, passing a list of years and a seed for all
        ///		random number generators in the model.  This is an internal constructor
        ///		and may only be used by classes within the Rabies_Model_Core namespace.
        /// </summary>
        /// <param name="Rnd">The random number generator to be used by the background</param>
        /// <param name="Name">
        ///		The name to assign to this background.  An ArgumentException is raised if
        ///		Name is zero length.
        ///	</param>
        /// <param name="KeepAllAnimals">
        ///		A flag indicating whether a record of all animals should be kept during
        ///		a run.
        ///	</param>
        /// <param name="YList">
        ///		The list of years.  An ArgumentException exception is raised if YList is empty.
        ///	</param>
        ///	<param name="DList">
        ///		A list of diseases that will affect the animals in this background.
        ///	</param>
        public cBackground(cUniformRandom Rnd, string Name, bool KeepAllAnimals, cYearList YList, cDiseaseList DList)
        {
            if (Rnd == null)
            {
                throw new ArgumentNullException("Rnd");
            }
            if (YList == null)
            {
                throw new ArgumentNullException("YList");
            }
            if (DList == null)
            {
                throw new ArgumentNullException("DList");
            }

            // make sure that Name is not zero length
            if (string.IsNullOrEmpty(Name))
            {
                throw new ArgumentException("Name must not be zero length.", "Name");
            }
            // make sure the Years list contains at least one year
            if (YList.Count == 0)
            {
                throw new ArgumentException("Year list must contain at least one year.",
                                            "Years");
            }
            // create the random number generator
            RandomNum          = Rnd;
            RandomNum.MinValue = 0;
            RandomNum.MaxValue = 100;
            // copy the name
            this.Name = Name;
            // create a super cell list
            SuperCells = new cSuperCellList();
            // create a master cell list
            Cells = new cMasterCellList(this, RandomNum);
            // generate winter and animal lists
            Years         = YList;
            Years.YearRnd = RandomNum;
            // create the master list of animals
            Animals = new cMasterAnimalList(1, KeepAllAnimals, RandomNum);
            // create the list of diseases
            Diseases = DList;
            // create the strategy list
            Strategies      = new cStrategyList();
            StrategyCounter = 0;
            // set have run weekly events to false
            mvarHaveRunWeeklyEvents = false;
            // scramble list is false by default
            ScrambleList = false;
            // abort on disease disappearance is true by default
            AbortOnDiseaseDisappearance = true;
            // prevent incest flag - set to false by default
            PreventIncest = false;
        }
 /// <summary>
 ///		Initialize the background specifying the initial number of years and their
 ///		winter bias.
 /// </summary>
 /// <param name="Rnd">The random number generator to be used by the background</param>
 /// <param name="Name">
 ///		The name to assign to this background.  An ArgumentException is raised if
 ///		Name is zero length.
 ///	</param>
 /// <param name="KeepAllAnimals">
 ///		A flag indicating whether a record of all animals should be kept during
 ///		a run.
 ///	</param>
 /// <param name="NYears">
 ///		The initial number of years. An ArgumentException is raised in NYears is
 ///		less than or equal to zero.
 ///	</param>
 /// <param name="WinterBias">The winter bias of the initial years.</param>
 public cBackground(cUniformRandom Rnd, string Name, bool KeepAllAnimals, int NYears, enumWinterType WinterBias)
 {
     if (Rnd == null)
     {
         throw new ArgumentNullException("Rnd");
     }
     // reference the random number generator
     RandomNum          = Rnd;
     RandomNum.MinValue = 0;
     RandomNum.MaxValue = 100;
     // make sure that Name is not zero length
     if (string.IsNullOrEmpty(Name))
     {
         throw new ArgumentException("Name must not be zero length.", "Name");
     }
     // make sure NYears > 0
     if (NYears <= 0)
     {
         throw new ArgumentException("NYears must be greater than 0.", "NYears");
     }
     // copy the name
     this.Name = Name;
     // create a super cell list
     SuperCells = new cSuperCellList();
     // create a master cell list
     Cells = new cMasterCellList(this, RandomNum);
     // create list of years
     Years = new cYearList(NYears, RandomNum, WinterBias);
     // create the master list of animals
     Animals = new cMasterAnimalList(1, KeepAllAnimals, RandomNum);
     // create the list of diseases
     Diseases = new cDiseaseList(RandomNum);
     // create the strategy list
     Strategies      = new cStrategyList();
     StrategyCounter = 0;
     // set have run weekly events to false
     mvarHaveRunWeeklyEvents = false;
     // scramble list is false by default
     ScrambleList = false;
     // abort on disease disappearance is true by default
     AbortOnDiseaseDisappearance = true;
     // prevent incest flag - set to false by default
     PreventIncest = false;
 }