ConditionalProbability( MDCObj,CurrentVar,VarParent,VectorValue )

function LogProbability = ConditionalProbability( MDCObj,CurrentVar,VarParent,VectorValue )
% P(CurrentVar | VarParent )
% VectorValue = [ CurrentVarValue, VarparentValue ];
% C = size( ClassSample,2 );
        MDC = struct( MDCObj );
        N = MDC.CaseLength;
        
        if VectorValue( CurrentVar ) == -1 
           LogProbability = 0;
           return
        end
       
        OriginalSample = MDC.OriginalSample;
        VarRangeLength = MDC.AllRangeLength( CurrentVar );
        ParentClassValue = VectorValue( VarParent );
        VarParent = VarParent( find( ParentClassValue ~= -1 )); %#ok<FNDSB> 
        UsedSample = DiscardNoneExist( OriginalSample,[ CurrentVar,VarParent ] );    
        M = N - sum( UsedSample ) ;
        
        if isempty( VarParent ) == 1 % no parent for Topo(q)
           counter = 0;
           for p=1:N
                if UsedSample( p )==0 && OriginalSample( p,CurrentVar ) == VectorValue( CurrentVar )
                   counter = counter + 1;
                end
           end
           counter1 = M;       
       elseif isempty( VarParent ) == 0 % At least one parent
              % calculate P(Vi |Parent(Vi)),s1 is for how many samples takes the value in VectorValue 
              counter=0;counter1=0; D = size( VarParent,2 );  
                for p=1:N
                    if UsedSample( p ) == 0
                         Symbol = 1;
                         for u = 1:D
                               if VectorValue( VarParent( u ) ) >= 0 && OriginalSample( p,VarParent( u ) ) ~= VectorValue( VarParent( u ) )
                                    Symbol = 0;
                                    break;
                               end     
                         end
                         if Symbol == 1                      
                               counter1 = counter1 + 1;
                               if OriginalSample( p,CurrentVar ) == VectorValue( CurrentVar )
                                  counter = counter + 1;
                               end
                         end
                    end 
                end
        end
       %    counter
       %    counter1
      
       %if counter1 == 0
       %     LogProbability = -log(N);
       % elseif counter == 0 
       %     LogProbability = -log(counter1 + VarRangeLength) ;
       % else
       %     LogProbability = log2( counter/counter1 );
       % end
            % The laplace method for adjusting parameter is used here.
            LogProbability = log2(( counter + 1 )/( counter1 + VarRangeLength   ));

  end