Need a sample .inp file format

Dear lammps users,

I need to use angle coefficient (potential) to constrain the structure of carbon nanotubes during the simulation, otherwise it will be deformed. Now i am having the .pdb file for CNT.The angle information is not getting from the pdb file.Thats why I need the a .psf file .One option i found to create .psf file is by using both the .pgn file and pdb file.But for creating .pgn file, an .inp file is needed.I didn’t get any sample .inp file format.if anyone is having a sample .inp file format ,please send me .

thanking you,

Your email doesn't make a lot of sense. None of the extensions you
talk about are standardized. They certainly have no relation to
lammps. That being said, whether you need angle definitions or not
depends on the force field you are using. With a suitable manybody
potential this is not needed. If however you do go for a pairwise
additive force field, you will also need to define dihedrals and
particularly proper dihedrals to keep the tube flat.

I suggest you spend some more time researching what else people have
done to simulate nanotubes. The mailing list archives for example have
lots of questions on those (and answers) and then there are a
gazillion of publications.