power

The power of a piece is its material value
Piece typepower
pawn1
knight3
bishop3
rook5
queen9
king0
empty square0

The power of a set of squares in a position is the sum of the power of all the pieces on squares in that set in the position.

power filter

The power filter consists of the word power followed by a set filter:
      power A

A power filter has a numeric value equal to the power of the pieces on the squares denoted by its set filter.

Thus, power A>= 15 matches positions where the power (material value) of the White pieces is at least 15.

The diagram below shows the earliest first prize win study with an initial total power of 7:

V. Kosek 1926
(found from CQL file: power7firstprize.cql)

The power filter can also be used to find material imbalances, as in the study below where black wins despite having a large material advantage, and white having only a single pawn:

T. Dawson 1945
(found from CQL file: powerA1alarge.cql)

Examples

The power filter is used in massivestalemate.cql, pinstalemate.cql, and powerdifference-stalemate.cql.