public int GetHashCode(MultiSet <T> obj)
{
Utils.ThrowException(obj == null ? new ArgumentNullException("obj") : null);
int hashCode = 0;
foreach (KeyValuePair <T, int> item in obj)
{
hashCode ^= item.Key.GetHashCode() ^ item.Value.GetHashCode();
}
return(hashCode);
}
public bool Equals(MultiSet <T> .ReadOnly x, MultiSet <T> .ReadOnly y)
{
if (x == null && y == null)
{
return(true);
}
if (x == null || y == null)
{
return(false);
}
return(Equals(x.Inner, y.Inner));
}
public bool Equals(MultiSet <T> x, MultiSet <T> y)
{
if (x == null && y == null)
{
return(true);
}
if (x == null || y == null)
{
return(false);
}
return(x.Count == y.Count && MultiSet <T> .Difference(x, y).Count == 0);
}
public static double JaccardSimilarity(MultiSet <T> a, MultiSet <T> b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
MultiSet <T> c = Intersection(a, b);
double div = (double)(a.Count + b.Count - c.Count);
if (div == 0)
{
return(1);
} // *** if both sets are empty, the similarity is 1
return((double)c.Count / div);
}
bool IEqualityComparer.Equals(object x, object y)
{
if (x is MultiSet <T> )
{
x = new MultiSet <T> .ReadOnly((MultiSet <T>) x);
}
if (y is MultiSet <T> )
{
y = new MultiSet <T> .ReadOnly((MultiSet <T>) y);
}
Utils.ThrowException((x != null && !(x is MultiSet <T> .ReadOnly)) ? new ArgumentTypeException("x") : null);
Utils.ThrowException((y != null && !(y is MultiSet <T> .ReadOnly)) ? new ArgumentTypeException("y") : null);
return(Equals((MultiSet <T> .ReadOnly)x, (MultiSet <T> .ReadOnly)y));
}
public static MultiSet <T> Difference(MultiSet <T> a, MultiSet <T> b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
MultiSet <T> c = new MultiSet <T>(a.Comparer); // *** inherits comparer from a (b is expected to have the same comparer)
foreach (KeyValuePair <T, int> item in a)
{
int bCount = b.GetCount(item.Key);
int cCount = item.Value - bCount;
if (cCount > 0)
{
c.mItems.Add(item.Key, cCount);
}
}
return(c);
}
public static MultiSet <T> Intersection(MultiSet <T> a, MultiSet <T> b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
MultiSet <T> c = new MultiSet <T>(a.Comparer); // *** inherits comparer from a (b is expected to have the same comparer)
if (b.Count < a.Count)
{
MultiSet <T> tmp; tmp = a; a = b; b = tmp;
}
foreach (KeyValuePair <T, int> item in a)
{
int bCount = b.GetCount(item.Key);
if (bCount > 0)
{
c.mItems.Add(item.Key, Math.Min(item.Value, bCount));
}
}
return(c);
}
// *** IContentEquatable<MultiSet<T>> interface implementation ***
public bool ContentEquals(MultiSet <T> other)
{
if (other == null || Count != other.Count)
{
return(false);
}
foreach (KeyValuePair <T, int> item in mItems)
{
int count;
if (other.mItems.TryGetValue(item.Key, out count))
{
if (count != item.Value)
{
return(false);
}
}
else
{
return(false);
}
}
return(true);
}
public int GetHashCode(MultiSet <T> .ReadOnly obj)
{
Utils.ThrowException(obj == null ? new ArgumentNullException("obj") : null);
return(GetHashCode(obj.Inner));
}
// *** IContentEquatable<MultiSet<T>.ReadOnly> interface implementation ***
public bool ContentEquals(MultiSet <T> .ReadOnly other)
{
return(other != null && mSet.ContentEquals(other.Inner));
}
public ReadOnly(BinarySerializer reader)
{
mSet = new MultiSet <T>(reader); // throws ArgumentNullException, serialization-related exceptions
}
public ReadOnly(MultiSet <T> set)
{
Utils.ThrowException(set == null ? new ArgumentNullException("set") : null);
mSet = set;
}
public static double JaccardSimilarity(MultiSet <T> .ReadOnly a, MultiSet <T> .ReadOnly b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
return(JaccardSimilarity(a.Inner, b.Inner));
}
public static MultiSet <T> Difference(MultiSet <T> .ReadOnly a, MultiSet <T> .ReadOnly b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
return(Difference(a.Inner, b.Inner));
}
