import IMP import IMP.core as core import IMP.atom as atom import IMP.em2d as em2d import IMP.em as em import IMP.algebra as alg import IMP.container import random # An Optimizer score to get the values of the statistics after a given set # of evaluations class WriteStatisticsOptimizerScore(IMP.OptimizerState): count =0 def __init__(self): IMP.OptimizerState.__init__(self) count = 0 def update(self): if (self.count!=10): self.count += 1 return else: self.count=0 o=self.get_optimizer() m=o.get_model() m.show_restraint_score_statistics() m.show_all_statistics() #for i in range(0,m.get_number_of_restraints()): # r=m.get_restraint(i) # print "restraint",r.get_name(),"value",r.evaluate(False) def do_show(self, stream): print >> stream, ps # Get model from PDB file IMP.set_log_level(IMP.TERSE) m = IMP.Model() prot = atom.read_pdb(em2d.get_example_path("1z5s.pdb"),m,atom.ATOMPDBSelector()) atom.add_radii(prot) # get the chains chains = atom.get_by_type(prot,atom.CHAIN_TYPE) print "there are",len(chains),"chains in 1z5s.pdb" # set the chains as rigid bodies native_chain_centers = [] rigid_bodies= [] for c in chains: atoms=core.get_leaves(c) rbd=core.RigidBody.setup_particle(c,atoms) rigid_bodies.append(rbd) print "chain has",rbd.get_number_of_members(), \ "atoms","coordinates: ",rbd.get_coordinates() native_chain_centers.append(rbd.get_coordinates()) bb=alg.BoundingBox3D(alg.Vector3D(-25, -40,-60), alg.Vector3D( 25, 40, 60)) # rotate and translate the chains for rbd in rigid_bodies: # rotation rotation= alg.get_random_rotation_3d() transformation1=alg.get_rotation_about_point(rbd.get_coordinates(),rotation) # translation transformation2=alg.Transformation3D(alg.get_random_vector_in(bb)) # Apply final_transformation = alg.compose(transformation1,transformation2) core.transform(rbd,final_transformation) print "Writing transformed assembly" atom.write_pdb (prot,"1z5s-transformed.pdb") # set distance restraints measusring some distances between rigid bodies # for the solution. d01 = alg.get_distance(native_chain_centers[0],native_chain_centers[1]) r01 = core.DistanceRestraint(core.Harmonic(d01,1),chains[0],chains[1]) r01.set_name("distance 0-1") d12 = alg.get_distance(native_chain_centers[1],native_chain_centers[2]) r12 = core.DistanceRestraint(core.Harmonic(d12,1),chains[1],chains[2]) r12.set_name("distance 1-2") d23 = alg.get_distance(native_chain_centers[2],native_chain_centers[3]) r23 = core.DistanceRestraint(core.Harmonic(d23,1),chains[2],chains[3]) r23.set_name("distance 2-3") d30 = alg.get_distance(native_chain_centers[3],native_chain_centers[0]) r30 = core.DistanceRestraint(core.Harmonic(d30,1),chains[3],chains[0]) r30.set_name("distance 3-0") print "Distances in the solution: d01 =", \ d01,"d12 =",d12,"d23 =",d23,"d30 =",d30 # set distance restraints print "adding distance restraints " for r in [r01,r12,r23,r30]: m.add_restraint(r) print "model has ",m.get_number_of_restraints(),"restraints" # set em2D restraint srw = em.SpiderImageReaderWriter() selection_file=em2d.get_example_path("all-1z5s-projections.sel") images_to_read_names=[IMP.get_relative_path(selection_file, x) for x in em2d.read_selection_file(selection_file)] em_images =em.read_images(images_to_read_names,srw) print len(em_images),"images read" em2d_restraint = em2d.Em2DRestraint() apix=1.5 # sampling rate of the available EM images # resolution at which you want to generate the projections of the model # In principle you want "perfect" projections, so use the highest resolution resolution=1 # Number of projections to use for the initial registration # (coarse registration) to estimate the registration parameters n_projections=20 # This method (recommended) uses preprocessing of the images and projections # to speed-up the registration coarse_registration_method = 1 # use true if you want to save the projections from the model that best # match the Em images save_match_images = False em2d_restraint.initialize(apix,resolution,n_projections, coarse_registration_method,save_match_images) em2d_restraint.set_images(em_images) em2d_restraint.set_name("em2d restraint") container = IMP.container.ListSingletonContainer(core.get_leaves(prot)) em2d_restraint.set_particles(container) em2d_restraints_set=IMP.RestraintSet() # The next two lines are commented, because the optimization of the example # is expensive. To run the full example, uncomment them (It can take a few # hours). #em2d_restraints_set.add_restraint(em2d_restraint) #em2d_restraints_set.set_weight(1000) # weight for the em2D restraint print "adding em2d restraint " m.add_restraint(em2d_restraints_set) # Add all restraints to a model print "model has ",m.get_number_of_restraints(),"restraints" # MONTECARLO OPTIMIZATION s=core.MonteCarlo(m) # Add movers for the rigid bodies movers=[] for rbd in rigid_bodies: movers.append(core.RigidBodyMover(rbd,5,2)) s.add_movers(movers) print "MonteCarlo sampler has",s.get_number_of_movers(),"movers" # Add an optimizer state to save intermediate configurations of the hierarchy o_state=atom.WritePDBOptimizerState(chains,"intermediate-step-%1%.pdb") o_state.set_skip_steps(10) s.add_optimizer_state(o_state) ostate2 = WriteStatisticsOptimizerScore() s.add_optimizer_state(ostate2) # Perform optimization # m.set_gather_statistics(True) # Writes a lot of information! temperatures=[200,100,60,40,20,5] optimization_steps = 200 for temp in temperatures: s.optimize(optimization_steps) atom.write_pdb(prot,"solution.pdb") # Check that the optimization achieves distances close to th solution print "*** End optimization ***" new_centers = [] for rbd in rigid_bodies: print "chain has",rbd.get_number_of_members(), \ "atoms","coordinates: ",rbd.get_coordinates() new_centers.append(rbd.get_coordinates()) d01 = alg.get_distance(new_centers[0],new_centers[1]) d12 = alg.get_distance(new_centers[1],new_centers[2]) d23 = alg.get_distance(new_centers[2],new_centers[3]) d30 = alg.get_distance(new_centers[3],new_centers[0]) print "Distances at the end of the optimization: d01 =", \ d01,"d12 =",d12,"d23 =",d23,"d30 =",d30