\cdbalgorithm{take}{}

Replace a sum, product or list with a subset of its terms, factors or
 elements. Example,
\begin{screen}{1,2,4,5,7,8}
A+B+C+D+E;
@take(%){1,3};
B+D;
{A,B,C,D,E};
@take(%){4};
\{ E \};
A*B*C*D*E;
@take(%){2..\infty};
C*D*E;
\end{screen}
As usual, a range can be open by setting the second boundary
to \texcommand{infty}.  In order to select terms based on pattern
matching, see \subscommand{take\_match}

\cdbseealgo{take_match}
