
4.21 vector
Vectors are elements of a free module over the basering with basis
gen(1) , gen(2) , ... .
Like polynomials they
can only be defined or accessed with respect to the basering.
Each vector belongs to a free module of rank equal to the biggest index
of a generator with nonzero coefficient. Since generators with zero
coefficients need not be written any vector may be considered
also as an element of a free module of higher rank.
(E.g., if f and g are polynomials then
f*gen(1)+g*gen(3)+gen(4) may also be written as [f,0,g,1]
or as [f,0,g,1,0] .)
Note that the elements of a vector have to be
surrounded by square brackets ([ , ] )
(cf. Representation of mathematical objects).
