Shows how to modify the internal coordinate system of a protein. The backtone torsion angles are all set to PHI=-60, PSI=-45; the protein is thus folded into a very long alpha helix.
import math e=io.LoadEntity('../entity/sdh.pdb') c=e.FindChain('A') edi=e.EditICS(mol.EditMode.BUFFERED_EDIT) for r in c.GetResidueList(): phi=r.GetPhiTorsion() psi=r.GetPsiTorsion() if phi.IsValid(): edi.SetTorsionAngle(phi, math.radians(-60)) if psi.IsValid(): edi.SetTorsionAngle(psi, math.radians(-45)) edi.UpdateXCS() g=gfx.Entity('helix', e.Select('aname=CA,N,O,C,CB')) scene.Add(g) scene.SetCenter(g.GetCenter())