When using factor, Pari prints the factors of a polynomial and their multiplicities. When using, say, polcyclofactors, however, the cyclotomic factors of the polynomial are listed as a vector, without multiplicity.
Is there are way to mimic polcyclofactors when just simply factoring polynomials? So, to just display the factors of the polynomial as a vector, without worrying about multiplicities?
Yes. The function factor returns a two column matrix. If you are only interested in the primes, not the multiplicities you can select just the first column:
For example:
factor(120)[,1]
If you were only interested in the multiplicities you would do [,2]. If you need the result as a vector rather than a column vector (the two types are mostly interchangeable), then you also need to add a conversion:
Vec(factor(120)[,1])
Although, I have done my examples with an integer, it also works with polynomials.
Vec(factor((1+x)^7*(1+x^2)^3)[,1])
A variant on Andrew's answer: you can convert a matrix into the vector of its columns using Vec, then (multi-)assign individual columns to new variables, so that
[P] = Vec(factor(120));
sets P to the vector of irreducible factors and
[P, E] = Vec(factor(120));
sets P and E to irreducible factors and multiplicities respectively. But the more messy factor()[,1] construct will be a little faster (because calling Vec causes extra copies).
