[GENERAL] Are there only 4 weights in PostgreSQL fulltext search?

[Gaini Rajeshwar]

Hi,
>From the readings and documentation, i understood that there are 4 weights *
A,B,C,D *(*1.0, 0.4, 0.2, 0.1* are the defalut values, which can be changed)
to rank the search results.
But using just these 4 weights is too less to rank the search results, as i
have many fields to use for ranking.
i am just wondering if we can use these existing 4 weights to specify new
weight?
Can we specify/use weights more than just these 4 weights? If it is
posiible, how can we do it?