Xapian devel - Aug 2013 - What does collection_freq means?

Hi, all:

I am confused with the concept of colletion_freq
There's no informations about it on http://xapian.org/docs/glossary.html
What does it means?

Thanks
Regards!
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> Hi, all:
> 
> I am confused with the concept of colletion_freq
> There's no informations about it on
http://xapian.org/docs/glossary.html
> What does it means?
The number of times the term appears across all documents.

Thanks, Matt.

And some other questions:
1.
http://xapian.org/docs/sourcedoc/html/classXapian_1_1Weight_1_1Internal.html
    Xapian::doccount collection_size
                              Number of documents in the collection.
    What's the difference bewteen collection_size and
doccount(Xapian::doccount  get_doccount() const;).

2 On this page, http://xapian.org/docs/bm25.html
    *(k3+1)q*
(k3+q) ?  *(k1+1)f*
(k1L+f) ?log *(r+0.5)(N-n-R+r+0.5)*
(n-r+0.5)(R-r+0.5)   .   f is the wdf, the within document frequency,

   But in the code BM25Weight::get_maxpart(),
   double wdf_max(get_wdf_upper_bound()) is used, what's the difference
between f(wdf) and wdf_max.
   If they are not the same, why wdf_max is used

Really appreciate your help!




2013/8/27 Matt Chaput <matt at whoosh.ca>
> > Hi, all:
> >
> > I am confused with the concept of colletion_freq
> > There's no informations about it on
http://xapian.org/docs/glossary.html
> > What does it means?
>
> The number of times the term appears across all documents.
>
>
> _______________________________________________
> Xapian-devel mailing list
> Xapian-devel at lists.xapian.org
> http://lists.xapian.org/mailman/listinfo/xapian-devel
>
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