[Biopython] is_na()?

[Peter Cock]

On Thu, Oct 17, 2013 at 9:33 AM, David Dufour Rausell
<ddufour at pcb.ub.cat> wrote:
> Hello,
>
> I would like to know if there is a function like is_aa(residue) but to test if
> a residue is RNA? Basically, what I want to know if a chain is RNA or not.
> Thanks in advance.
>
> David Dufour Rausell

Hello David,

Are you asking about residues in 3D structures (e.g. from Bio.PDB),
letters in sequences (e.g. strings or Seq objects), or another context?

If sequence and using Seq objects, you may be able to look at the
alphabet. However, most file formats do not define this explicitly, but
you can tell the SeqIO parsers via the optional alphabet argument.

Peter