org.grouplens.lenskit.util

Interface ScoredItemAccumulator

All Known Implementing Classes:

TopNScoredItemAccumulator, UnlimitedScoredItemAccumulator

public interface ScoredItemAccumulator

Accumulate a sorted list of scored items.

Method Summary

Modifier and Type	Method and Description
List<ScoredId>	finish() Accumulate the scores into a sorted scored list and reset the accumulator.
LongSet	finishSet() Accumulate the scored items into a set.
MutableSparseVector	finishVector() Accumulate the scores into a mutable sparse vector and reset the accumulator.
boolean	isEmpty() Query whether the accumulator is empty.
void	put(long item, double score) Put a new item in the accumulator.
int	size() Get the number of items in the accumulator.

Method Detail

isEmpty

boolean isEmpty()

Query whether the accumulator is empty.

Returns:

true if the accumulator has no items.

size

int size()

Get the number of items in the accumulator.

Returns:

The number of items accumulated so far, up to the maximum items desired from the accumulator.

put

void put(long item,
         double score)

Put a new item in the accumulator. Putting the same item twice does not replace the previous entry - it adds a new entry with the same ID.

Parameters:

item - The item to add to the accumulator.

score - The item's score.

finish

List<ScoredId> finish()

Accumulate the scores into a sorted scored list and reset the accumulator. Items are sorted in decreasing order of score.

After this method is called, the accumulator is ready for another accumulation.

Returns:

The sorted, scored list of items.

finishVector

MutableSparseVector finishVector()

Accumulate the scores into a mutable sparse vector and reset the accumulator.

After this method is called, the accumulator is ready for another accumulation.

Returns:

A MutableSparseVector of items.

finishSet

LongSet finishSet()

Accumulate the scored items into a set.

Returns:

The set of items accumulated.