public double SharedWordRatio(WeightedItemVector <T> other)
{
var topThis = this._itemWeights.OrderByDescending(n => n.Value).Select(n => n.Key).Take(5);
var topOther = other._itemWeights.OrderByDescending(n => n.Value).Select(n => n.Key).Take(5);
return(topThis.Intersect(topOther).Count() / (double)topThis.Union(topOther).Count());
}
public double DotProduct(WeightedItemVector <T> b)
{
return(this * b);
}