/// <summary>
/// Synchronous version
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="items"></param>
/// <param name="topSize"></param>
/// <returns></returns>
public T[] GetTopN <T>(IEnumerable <T> items, int topSize) where T : IComparable <T>
{
BoundedOrderedQueue <T> queue = new BoundedOrderedQueue <T>(topSize);
foreach (T i in items)
{
queue.Add(i);
}
return(queue.ToArray());
}
public T[] GetTopNPar <T>(IEnumerable <T> items, int topSize) where T : IComparable <T>
{
BoundedOrderedQueue <T> queue = new BoundedOrderedQueue <T>(topSize);
object monitor = new object();
Parallel.ForEach(
items,
() => new BoundedOrderedQueue <T>(topSize), // initial state
(it, state, partial) => { // local body
partial.Add(it);
return(partial);
},
(p) => { // final aggregation
lock (monitor)
queue.Merge(p);
});
return(queue.ToArray());
}
public T[] ParallelForGetTopN <T>(IEnumerable <T> items, int topSize) where T : IComparable <T>
{
BoundedOrderedQueue <T> boundedOrderedQueue = new BoundedOrderedQueue <T>(topSize);
Parallel.ForEach(items,
() => new BoundedOrderedQueue <T>(1),
(item, state, queue) =>
{
queue.Add(item);
return(queue);
}, queue =>
{
lock (queue)
{
boundedOrderedQueue.Merge(queue);
}
});
return(boundedOrderedQueue.ToArray());
}
public void Merge(BoundedOrderedQueue <T> ol)
{
}
