public PositionalIndex Decompress(CompressedIndex compressedIndex)
{
//return compressedIndex.Decompress();
//foreach (var item in compressedIndex.PostingsByTokens)
// result.(item.Key, item.Value);
var mapping = new List <RawDataMapping>();
foreach (var compressedPosting in compressedIndex.PostingsByToken)
{
mapping.Add(new RawDataMapping(compressedPosting.Key, compressedPosting.Value.CompressedListOfDocumentIds));
mapping.AddRange(compressedPosting.Value.OccurrencesList.Select(x => new RawDataMapping(compressedPosting.Key, x)));
}
new CompressUtility().DecompressList(mapping);
var result = new PositionalIndex();
foreach (var tokenPosting in compressedIndex.PostingsByToken)
{
var postingIntList = mapping.Where(x => x.Token == tokenPosting.Key)
.OrderBy(x => x.Id)
.Select(x => x.RawData)
.ToList();
var decompressedPosting = tokenPosting.Value.Decompress(postingIntList);
result.AddDecompressedPosting(decompressedPosting);
}
return(result);
}
public CompressedIndex Compress(PositionalIndex uncompressedIndex)
{
CompressedIndex compressedIndex = CopyDataToCompressedIndex(uncompressedIndex);
var mapping = new List <RawDataMapping>();
foreach (var tokenPosting in compressedIndex.PostingsByToken)
{
mapping.AddRange(tokenPosting.Value.RawData.Select(list => new RawDataMapping(tokenPosting.Key, list)));
}
new CompressUtility().CompressIntList(mapping);
foreach (var tokenPosting in compressedIndex.PostingsByToken)
{
var postingCompressedStrings = mapping.Where(x => x.Token == tokenPosting.Key)
.OrderBy(x => x.Id)
.Select(x => x.CompressedData)
.ToList();
tokenPosting.Value.PlaceCompressedData(postingCompressedStrings);
}
return(compressedIndex);
}
private CompressedIndex CopyDataToCompressedIndex(PositionalIndex uncompressedIndex)
{
var result = new CompressedIndex();
foreach (var item in uncompressedIndex.PostingsByToken)
//Parallel.ForEach(uncompressedIndex.IndexByTokens, new ParallelOptions() { MaxDegreeOfParallelism = 50 }, (item) =>
{
result.AddPosting(item.Key, item.Value);
}
return(result);
}