PROCESSOR FOR FAST CONTEXTUAL SEARCHING

Words having selected characteristics in a corpus of documents are found using a data processor arranged to execute queries. Memory stores an index structure in which entries in the index structure map words and marks for words having the selected characteristics to locations within documents in the corpus. Entries in the index structure represent words and other entries represent marks with the location information of a marked word. The entries for the marks can be tokens coalesced with prefixes of respective marked words or adjacent. A query processor forms a modified query by adding a mark for a word to the query. The processor executes the modified query.