FUNCTION: read_in - enter a valid weight sequence

CALLING SEQUENCE:
read_in(p1,...,pt)

PARAMETERS:
p1,...,pt - positive integers (= weights)

SYNOPSIS:

• read_in(p1,...,pt) invokes a variety of internal routines; setting internal variables (mostly matrices, but also resetting remember tables etc.) for various computations. "read_in" formally returns NULL. In case one of the four tubular weight sequences has been entered, additional variables concerning the use of telescope functors will be set.

• The weights will automatically be ordered s.t. p1 <= p2 <= ... <= pt.

• Note that a chosen weight sequence remains valid until another weight sequence has been entered (invoking read_in again); in particular, only one weight sequence can be valid at a time.

EXAMPLES:

> with(tubular):

> read_in(3,3,3);

> read_in(2,3,5);