\cdbproperty{Weight}{\it label={\sf name}, value={\sf rational}}

Attach a labelled weight to an object, which can subsequently be used
in the algorithms \subscommand{keep\_weight}
and \subscommand{drop\_weight}. See the documentation of those
algorithms for examples.

\cdbseealgo{keep_weight}
\cdbseealgo{drop_weight}

