static DefaultSimilarity()
{
for (int i = 0; i < 256; i++)
{
NORM_TABLE[i] = SmallFloat.Byte315ToFloat((sbyte)i);
}
}
static BM25Similarity()
{
for (int i = 0; i < 256; i++)
{
float f = SmallFloat.Byte315ToFloat((sbyte)i);
NORM_TABLE[i] = 1.0f / (f * f);
}
}
/// <summary>
/// 得到文档某字段的Norm
/// </summary>
/// <param name="reader"></param>
/// <param name="field"></param>
/// <param name="docId"></param>
/// <returns></returns>
public static float GetNorm(IndexReader reader, string field, int docId)
{
return(SmallFloat.Byte315ToFloat(reader.Norms(field)[docId]));
}