[pylucene-dev] Downcast of TermFreqVector to TermPositionVector

[Andi Vajda]

On Mon, 30 Jul 2007, Bernhard Jung wrote:

> I stumbled across the problem of using term vectors with position and
> offset information in pylucene. I use fields with
> Field.TermVectors.WITH_POSITIONS_OFFSETS set and the getTermFreqVector
> method of IndexReader to retrieve the term vector, but this is of type
> TermFrequencyVector and not of TermPositionVector (a sub-interface of
> TermFrequencyVector), which would provide the method getTermPositions
> and getOffsets that I want to use.
>
> I patched lucene.cpp of the latest subversion trunk (of 2007-07-30) to
> provide downcast methods from TermFrequencyVector to TermPositionVector
> (isTermPositionVector and toTermPositionVector).
>
> I'd like to share this patch or be corrected if I somehow follow a wrong
> way to get the positions and offsets of terms in a document.
>
> Find attached the patch and an example script that makes use of the
> downcasted TermPositionVector.

I checked-in your patch into svn trunk revision 337.

Thank you for your contribution !

Andi..