import IMP.em import IMP.core import IMP.atom IMP.set_log_level(IMP.SILENT) m= IMP.Model() #1. setup the input protein ##1.1 select a selector. sel=IMP.atom.NonWaterPDBSelector() ##1.2 read the protein mh=IMP.atom.read_pdb(IMP.em.get_example_path("input.pdb"),m,sel) ps=IMP.Particles(IMP.core.get_leaves(mh)) IMP.atom.add_radii(mh) #2. read the density map resolution=8. voxel_size=1.5 dmap=IMP.em.read_map(IMP.em.get_example_path("input.mrc"),IMP.em.MRCReaderWriter()) dmap.get_header_writable().set_resolution(resolution) #3. calculate the cross correlation between the density and the map print "The cross-correlation score is:",1.-IMP.em.compute_fitting_score(ps,dmap) #4. add a fitting restraint r= IMP.em.FitRestraint(ps, dmap) m.add_restraint(r) print "The fit of the particles in the density is:",r.evaluate(False)