def create_gtr(params): """ parse the arguments referring to the GTR model and return a GTR structure """ model = params.gtr gtr_params = params.gtr_params if model == 'infer': gtr = GTR.standard('jc', alphabet='aa' if params.aa else 'nuc') else: try: kwargs = {} if gtr_params is not None: for param in gtr_params: keyval = param.split('=') if len(keyval)!=2: continue if keyval[0] in ['pis', 'pi', 'Pi', 'Pis']: keyval[0] = 'pi' keyval[1] = list(map(float, keyval[1].split(','))) elif keyval[0] not in ['alphabet']: keyval[1] = float(keyval[1]) kwargs[keyval[0]] = keyval[1] else: print ("GTR params are not specified. Creating GTR model with default parameters") gtr = GTR.standard(model, **kwargs) infer_gtr = False except: print ("Could not create GTR model from input arguments. Using default (Jukes-Cantor 1969)") gtr = GTR.standard('jc', alphabet='aa' if params.aa else 'nuc') infer_gtr = False return gtr
def create_gtr(params): """ parse the arguments referring to the GTR model and return a GTR structure """ model = params.gtr gtr_params = params.gtr_params if model == 'infer': gtr = GTR.standard('jc', alphabet='aa' if params.aa else 'nuc') else: try: kwargs = {} if gtr_params is not None: for param in gtr_params: keyval = param.split('=') if len(keyval)!=2: continue if keyval[0] in ['pis', 'pi', 'Pi', 'Pis']: keyval[0] = 'pi' keyval[1] = list(map(float, keyval[1].split(','))) elif keyval[0] not in ['alphabet']: keyval[1] = float(keyval[1]) kwargs[keyval[0]] = keyval[1] else: print ("GTR params are not specified. Creating GTR model with default parameters") gtr = GTR.standard(model, **kwargs) infer_gtr = False except KeyError as e: print("\nUNKNOWN SUBSTITUTION MODEL\n") raise e return gtr
def create_gtr(params): """ parse the arguments referring to the GTR model and return a GTR structure """ model = params.gtr gtr_params = params.gtr_params if model == 'infer': gtr = GTR.standard('jc') else: try: kwargs = {} if gtr_params is not None: for param in gtr_params: keyval = param.split('=') if len(keyval) != 2: continue if keyval[0] in ['pis', 'pi', 'Pi', 'Pis']: keyval[0] = 'pi' keyval[1] = list(map(float, keyval[1].split(','))) elif keyval[0] not in ['alphabet']: keyval[1] = float(keyval[1]) kwargs[keyval[0]] = keyval[1] else: print( "GTR params are not specified. Creating GTR model with default parameters" ) gtr = GTR.standard(model, **kwargs) infer_gtr = False except: print( "Could not create GTR model from input arguments. Using default (Jukes-Cantor 1969)" ) gtr = GTR.standard('jc') infer_gtr = False return gtr
def infer_gene_gain_loss(path, rates=[1.0, 1.0]): # initialize GTR model with default parameters mu = np.sum(rates) gene_pi = np.array(rates) / mu gain_loss_model = GTR.custom(pi=gene_pi, mu=mu, W=np.ones((2, 2)), alphabet=np.array(['0', '1'])) # add "unknown" state to profile gain_loss_model.profile_map['-'] = np.ones(2) root_dir = os.path.dirname(os.path.realpath(__file__)) # define file names for pseudo alignment of presence/absence patterns as in 001001010110 sep = '/' fasta = sep.join([path.rstrip(sep), 'geneCluster', 'genePresence.aln']) # strain tree based on core gene SNPs nwk = sep.join([path.rstrip(sep), 'geneCluster', 'strain_tree.nwk']) # instantiate treetime with custom GTR t = TreeAnc(nwk, gtr=gain_loss_model, verbose=2) # fix leaves names since Bio.Phylo interprets numeric leaf names as confidence for leaf in t.tree.get_terminals(): if leaf.name is None: leaf.name = str(leaf.confidence) t.aln = fasta t.tree.root.branch_length = 0.0001 t.reconstruct_anc(method='ml') for n in t.tree.find_clades(): n.genepresence = n.sequence return t
def test_ancestral(): import os from Bio import AlignIO import numpy as np from treetime import TreeAnc, GTR root_dir = os.path.dirname(os.path.realpath(__file__)) fasta = str(os.path.join(root_dir, '../data/H3N2_NA_allyears_NA.20.fasta')) nwk = str(os.path.join(root_dir, '../data/H3N2_NA_allyears_NA.20.nwk')) for marginal in [True, False]: print('loading flu example') t = TreeAnc(gtr='Jukes-Cantor', tree=nwk, aln=fasta) print('ancestral reconstruction' + ("marginal" if marginal else "joint")) t.reconstruct_anc(method='ml', marginal=marginal) assert "".join(t.tree.root.sequence) == 'ATGAATCCAAATCAAAAGATAATAACGATTGGCTCTGTTTCTCTCACCATTTCCACAATATGCTTCTTCATGCAAATTGCCATCTTGATAACTACTGTAACATTGCATTTCAAGCAATATGAATTCAACTCCCCCCCAAACAACCAAGTGATGCTGTGTGAACCAACAATAATAGAAAGAAACATAACAGAGATAGTGTATCTGACCAACACCACCATAGAGAAGGAAATATGCCCCAAACCAGCAGAATACAGAAATTGGTCAAAACCGCAATGTGGCATTACAGGATTTGCACCTTTCTCTAAGGACAATTCGATTAGGCTTTCCGCTGGTGGGGACATCTGGGTGACAAGAGAACCTTATGTGTCATGCGATCCTGACAAGTGTTATCAATTTGCCCTTGGACAGGGAACAACACTAAACAACGTGCATTCAAATAACACAGTACGTGATAGGACCCCTTATCGGACTCTATTGATGAATGAGTTGGGTGTTCCTTTTCATCTGGGGACCAAGCAAGTGTGCATAGCATGGTCCAGCTCAAGTTGTCACGATGGAAAAGCATGGCTGCATGTTTGTATAACGGGGGATGATAAAAATGCAACTGCTAGCTTCATTTACAATGGGAGGCTTGTAGATAGTGTTGTTTCATGGTCCAAAGAAATTCTCAGGACCCAGGAGTCAGAATGCGTTTGTATCAATGGAACTTGTACAGTAGTAATGACTGATGGAAGTGCTTCAGGAAAAGCTGATACTAAAATACTATTCATTGAGGAGGGGAAAATCGTTCATACTAGCACATTGTCAGGAAGTGCTCAGCATGTCGAAGAGTGCTCTTGCTATCCTCGATATCCTGGTGTCAGATGTGTCTGCAGAGACAACTGGAAAGGCTCCAATCGGCCCATCGTAGATATAAACATAAAGGATCATAGCATTGTTTCCAGTTATGTGTGTTCAGGACTTGTTGGAGACACACCCAGAAAAAACGACAGCTCCAGCAGTAGCCATTGTTTGGATCCTAACAATGAAGAAGGTGGTCATGGAGTGAAAGGCTGGGCCTTTGATGATGGAAATGACGTGTGGATGGGAAGAACAATCAACGAGACGTCACGCTTAGGGTATGAAACCTTCAAAGTCATTGAAGGCTGGTCCAACCCTAAGTCCAAATTGCAGATAAATAGGCAAGTCATAGTTGACAGAGGTGATAGGTCCGGTTATTCTGGTATTTTCTCTGTTGAAGGCAAAAGCTGCATCAATCGGTGCTTTTATGTGGAGTTGATTAGGGGAAGAAAAGAGGAAACTGAAGTCTTGTGGACCTCAAACAGTATTGTTGTGTTTTGTGGCACCTCAGGTACATATGGAACAGGCTCATGGCCTGATGGGGCGGACCTCAATCTCATGCCTATA' print('testing LH normalization') from StringIO import StringIO from Bio import Phylo,AlignIO tiny_tree = Phylo.read(StringIO("((A:0.60100000009,B:0.3010000009):0.1,C:0.2):0.001;"), 'newick') tiny_aln = AlignIO.read(StringIO(">A\nAAAAAAAAAAAAAAAACCCCCCCCCCCCCCCCGGGGGGGGGGGGGGGGTTTTTTTTTTTTTTTT\n" ">B\nAAAACCCCGGGGTTTTAAAACCCCGGGGTTTTAAAACCCCGGGGTTTTAAAACCCCGGGGTTTT\n" ">C\nACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGT\n"), 'fasta') mygtr = GTR.custom(alphabet = np.array(['A', 'C', 'G', 'T']), pi = np.array([0.9, 0.06, 0.02, 0.02]), W=np.ones((4,4))) t = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=tiny_aln) t.reconstruct_anc('ml', marginal=True, debug=True) lhsum = (t.tree.root.marginal_profile.sum(axis=1) * np.exp(t.tree.root.marginal_subtree_LH_prefactor)).sum() print (lhsum) assert(np.abs(lhsum-1.0)<1e-6) t.optimize_branch_len()
def test_ancestral(): import os from Bio import AlignIO import numpy as np from treetime import TreeAnc, GTR root_dir = os.path.dirname(os.path.realpath(__file__)) fasta = str(os.path.join(root_dir, 'treetime_examples/data/h3n2_na/h3n2_na_20.fasta')) nwk = str(os.path.join(root_dir, 'treetime_examples/data/h3n2_na/h3n2_na_20.nwk')) for marginal in [True, False]: print('loading flu example') t = TreeAnc(gtr='Jukes-Cantor', tree=nwk, aln=fasta) print('ancestral reconstruction' + ("marginal" if marginal else "joint")) t.reconstruct_anc(method='ml', marginal=marginal) assert "".join(t.tree.root.sequence) == 'ATGAATCCAAATCAAAAGATAATAACGATTGGCTCTGTTTCTCTCACCATTTCCACAATATGCTTCTTCATGCAAATTGCCATCTTGATAACTACTGTAACATTGCATTTCAAGCAATATGAATTCAACTCCCCCCCAAACAACCAAGTGATGCTGTGTGAACCAACAATAATAGAAAGAAACATAACAGAGATAGTGTATCTGACCAACACCACCATAGAGAAGGAAATATGCCCCAAACCAGCAGAATACAGAAATTGGTCAAAACCGCAATGTGGCATTACAGGATTTGCACCTTTCTCTAAGGACAATTCGATTAGGCTTTCCGCTGGTGGGGACATCTGGGTGACAAGAGAACCTTATGTGTCATGCGATCCTGACAAGTGTTATCAATTTGCCCTTGGACAGGGAACAACACTAAACAACGTGCATTCAAATAACACAGTACGTGATAGGACCCCTTATCGGACTCTATTGATGAATGAGTTGGGTGTTCCTTTTCATCTGGGGACCAAGCAAGTGTGCATAGCATGGTCCAGCTCAAGTTGTCACGATGGAAAAGCATGGCTGCATGTTTGTATAACGGGGGATGATAAAAATGCAACTGCTAGCTTCATTTACAATGGGAGGCTTGTAGATAGTGTTGTTTCATGGTCCAAAGAAATTCTCAGGACCCAGGAGTCAGAATGCGTTTGTATCAATGGAACTTGTACAGTAGTAATGACTGATGGAAGTGCTTCAGGAAAAGCTGATACTAAAATACTATTCATTGAGGAGGGGAAAATCGTTCATACTAGCACATTGTCAGGAAGTGCTCAGCATGTCGAAGAGTGCTCTTGCTATCCTCGATATCCTGGTGTCAGATGTGTCTGCAGAGACAACTGGAAAGGCTCCAATCGGCCCATCGTAGATATAAACATAAAGGATCATAGCATTGTTTCCAGTTATGTGTGTTCAGGACTTGTTGGAGACACACCCAGAAAAAACGACAGCTCCAGCAGTAGCCATTGTTTGGATCCTAACAATGAAGAAGGTGGTCATGGAGTGAAAGGCTGGGCCTTTGATGATGGAAATGACGTGTGGATGGGAAGAACAATCAACGAGACGTCACGCTTAGGGTATGAAACCTTCAAAGTCATTGAAGGCTGGTCCAACCCTAAGTCCAAATTGCAGATAAATAGGCAAGTCATAGTTGACAGAGGTGATAGGTCCGGTTATTCTGGTATTTTCTCTGTTGAAGGCAAAAGCTGCATCAATCGGTGCTTTTATGTGGAGTTGATTAGGGGAAGAAAAGAGGAAACTGAAGTCTTGTGGACCTCAAACAGTATTGTTGTGTTTTGTGGCACCTCAGGTACATATGGAACAGGCTCATGGCCTGATGGGGCGGACCTCAATCTCATGCCTATA' print('testing LH normalization') from Bio import Phylo,AlignIO tiny_tree = Phylo.read(StringIO("((A:0.60100000009,B:0.3010000009):0.1,C:0.2):0.001;"), 'newick') tiny_aln = AlignIO.read(StringIO(">A\nAAAAAAAAAAAAAAAACCCCCCCCCCCCCCCCGGGGGGGGGGGGGGGGTTTTTTTTTTTTTTTT\n" ">B\nAAAACCCCGGGGTTTTAAAACCCCGGGGTTTTAAAACCCCGGGGTTTTAAAACCCCGGGGTTTT\n" ">C\nACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGTACGT\n"), 'fasta') mygtr = GTR.custom(alphabet = np.array(['A', 'C', 'G', 'T']), pi = np.array([0.9, 0.06, 0.02, 0.02]), W=np.ones((4,4))) t = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=tiny_aln) t.reconstruct_anc('ml', marginal=True, debug=True) lhsum = np.exp(t.sequence_LH(pos=np.arange(4**3))).sum() print (lhsum) assert(np.abs(lhsum-1.0)<1e-6) t.optimize_branch_len()
def test_GTR(): from treetime import GTR import numpy as np for model in ['Jukes-Cantor']: print('testing GTR, model:',model) myGTR = GTR.standard(model, alphabet='nuc') print('Frequency sum:', myGTR.Pi.sum()) assert (myGTR.Pi.sum() - 1.0)**2<1e-14 # the matrix is the rate matrix assert abs(myGTR.Q.sum(0)).sum() < 1e-14 # eigendecomposition is made correctly n_states = myGTR.v.shape[0] assert abs((myGTR.v.dot(myGTR.v_inv) - np.identity(n_states)).sum() < 1e-10) assert np.abs(myGTR.v.sum()) > 1e-10 # **and** v is not zero
def test_GTR(): from treetime import GTR import numpy as np for model in ['Jukes-Cantor', 'random']: print('testing GTR, model:',model) myGTR = GTR.standard(model, alphabet='nuc') print('Frequency sum:', myGTR.Pi.sum()) assert (myGTR.Pi.sum() - 1.0)**2<1e-14 # the matrix is the rate matrix assert abs(myGTR.Q.sum(0)).sum() < 1e-14 # eigendecomposition is made correctly n_states = myGTR.v.shape[0] assert abs((myGTR.v.dot(myGTR.v_inv) - np.identity(n_states)).sum() < 1e-10) assert np.abs(myGTR.v.sum()) > 1e-10 # **and** v is not zero
def test_seq_joint_lh_is_max(): """ For a single-char sequence, perform joint ancestral sequence reconstruction and prove that this reconstruction is the most likely one by comparing to all possible reconstruction variants (brute-force). """ from treetime import TreeAnc, GTR from treetime import seq_utils from Bio import Phylo, AlignIO import numpy as np mygtr = GTR.custom(alphabet = np.array(['A', 'C', 'G', 'T']), pi = np.array([0.91, 0.05, 0.02, 0.02]), W=np.ones((4,4))) tiny_tree = Phylo.read(StringIO("((A:.0060,B:.30)C:.030,D:.020)E:.004;"), 'newick') #terminal node sequences (single nuc) A_char = 'A' B_char = 'C' D_char = 'G' # for brute-force, expand them to the strings A_seq = ''.join(np.repeat(A_char,16)) B_seq = ''.join(np.repeat(B_char,16)) D_seq = ''.join(np.repeat(D_char,16)) # def ref_lh(): """ reference likelihood - LH values for all possible variants of the internal node sequences """ tiny_aln = AlignIO.read(StringIO(">A\n" + A_seq + "\n" ">B\n" + B_seq + "\n" ">D\n" + D_seq + "\n" ">C\nAAAACCCCGGGGTTTT\n" ">E\nACGTACGTACGTACGT\n"), 'fasta') myTree = TreeAnc(gtr=mygtr, tree = tiny_tree, aln =tiny_aln, verbose = 4) logLH_ref = myTree.ancestral_likelihood() return logLH_ref # def real_lh(): """ Likelihood of the sequences calculated by the joint ancestral sequence reconstruction """ tiny_aln_1 = AlignIO.read(StringIO(">A\n"+A_char+"\n" ">B\n"+B_char+"\n" ">D\n"+D_char+"\n"), 'fasta') myTree_1 = TreeAnc(gtr=mygtr, tree = tiny_tree, aln=tiny_aln_1, verbose = 4) myTree_1.reconstruct_anc(method='ml', marginal=False, debug=True) logLH = myTree_1.tree.sequence_LH return logLH ref = ref_lh() real = real_lh() print(abs(ref.max() - real) ) # joint chooses the most likely realization of the tree assert(abs(ref.max() - real) < 1e-10) return ref, real
def test_seq_joint_reconstruction_correct(): """ evolve the random sequence, get the alignment at the leaf nodes. Reconstruct the sequences of the internal nodes (joint) and prove the reconstruction is correct. In addition, compute the likelihood of the particular realization of the sequences on the tree and prove that this likelihood is exactly the same as calculated in the joint reconstruction """ from treetime import TreeAnc, GTR from treetime import seq_utils from Bio import Phylo, AlignIO from StringIO import StringIO import numpy as np try: from itertools import izip except ImportError: #python3.x izip = zip from collections import defaultdict def exclusion(a, b): """ Intersection of two lists """ return list(set(a) - set(b)) tiny_tree = Phylo.read( StringIO("((A:.060,B:.01200)C:.020,D:.0050)E:.004;"), 'newick') mygtr = GTR.custom(alphabet=np.array(['A', 'C', 'G', 'T']), pi=np.array([0.15, 0.95, 0.05, 0.3]), W=np.ones((4, 4))) seq = np.random.choice(mygtr.alphabet, p=mygtr.Pi, size=400) myTree = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=None, verbose=4) # simulate evolution, set resulting sequence as ref_seq tree = myTree.tree seq_len = 400 tree.root.ref_seq = np.random.choice(mygtr.alphabet, p=mygtr.Pi, size=seq_len) print("Root sequence: " + ''.join(tree.root.ref_seq)) mutation_list = defaultdict(list) for node in tree.find_clades(): for c in node.clades: c.up = node if hasattr(node, 'ref_seq'): continue t = node.branch_length p = mygtr.propagate_profile( seq_utils.seq2prof(node.up.ref_seq, mygtr.profile_map), t) # normalie profile p = (p.T / p.sum(axis=1)).T # sample mutations randomly ref_seq_idxs = np.array([ int(np.random.choice(np.arange(p.shape[1]), p=p[k])) for k in np.arange(p.shape[0]) ]) node.ref_seq = np.array([mygtr.alphabet[k] for k in ref_seq_idxs]) node.ref_mutations = [ (anc, pos, der) for pos, (anc, der) in enumerate(izip(node.up.ref_seq, node.ref_seq)) if anc != der ] for anc, pos, der in node.ref_mutations: print(pos) mutation_list[pos].append((node.name, anc, der)) print(node.name, len(node.ref_mutations), node.ref_mutations) # set as the starting sequences to the terminal nodes: alnstr = "" i = 1 for leaf in tree.get_terminals(): alnstr += ">" + leaf.name + "\n" + ''.join(leaf.ref_seq) + '\n' i += 1 print(alnstr) myTree.aln = AlignIO.read(StringIO(alnstr), 'fasta') myTree._attach_sequences_to_nodes() # reconstruct ancestral sequences: myTree._ml_anc_joint(debug=True) diff_count = 0 mut_count = 0 for node in myTree.tree.find_clades(): if node.up is not None: mut_count += len(node.ref_mutations) diff_count += np.sum(node.sequence != node.ref_seq) == 0 if np.sum(node.sequence != node.ref_seq): print( "%s: True sequence does not equal inferred sequence. parent %s" % (node.name, node.up.name)) else: print("%s: True sequence equals inferred sequence. parent %s" % (node.name, node.up.name)) print(node.name, np.sum(node.sequence != node.ref_seq), np.where(node.sequence != node.ref_seq), len(node.mutations), node.mutations) # the assignment of mutations to the root node is probabilistic. Hence some differences are expected assert diff_count / seq_len < 2 * (1.0 * mut_count / seq_len)**2 # prove the likelihood value calculation is correct LH = myTree.ancestral_likelihood() LH_p = (myTree.tree.sequence_LH) print("Difference between reference and inferred LH:", (LH - LH_p).sum()) assert ((LH - LH_p).sum()) < 1e-9 return myTree
def test_seq_joint_lh_is_max(): """ For a single-char sequence, perform joint ancestral sequence reconstruction and prove that this reconstruction is the most likely one by comparing to all possible reconstruction variants (brute-force). """ from treetime import TreeAnc, GTR from treetime import seq_utils from Bio import Phylo, AlignIO from StringIO import StringIO import numpy as np mygtr = GTR.custom(alphabet=np.array(['A', 'C', 'G', 'T']), pi=np.array([0.91, 0.05, 0.02, 0.02]), W=np.ones((4, 4))) tiny_tree = Phylo.read(StringIO("((A:.0060,B:.30)C:.030,D:.020)E:.004;"), 'newick') #terminal node sequences (single nuc) A_char = 'A' B_char = 'C' D_char = 'G' # for brute-force, expand them to the strings A_seq = ''.join(np.repeat(A_char, 16)) B_seq = ''.join(np.repeat(B_char, 16)) D_seq = ''.join(np.repeat(D_char, 16)) # def ref_lh(): """ reference likelihood - LH values for all possible variants of the internal node sequences """ tiny_aln = AlignIO.read( StringIO(">A\n" + A_seq + "\n" ">B\n" + B_seq + "\n" ">D\n" + D_seq + "\n" ">C\nAAAACCCCGGGGTTTT\n" ">E\nACGTACGTACGTACGT\n"), 'fasta') myTree = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=tiny_aln, verbose=4) logLH_ref = myTree.ancestral_likelihood() return logLH_ref # def real_lh(): """ Likelihood of the sequences calculated by the joint ancestral sequence reconstruction """ tiny_aln_1 = AlignIO.read( StringIO(">A\n" + A_char + "\n" ">B\n" + B_char + "\n" ">D\n" + D_char + "\n"), 'fasta') myTree_1 = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=tiny_aln_1, verbose=4) myTree_1.reconstruct_anc(method='ml', marginal=False, debug=True) logLH = myTree_1.tree.sequence_LH return logLH ref = ref_lh() real = real_lh() print(abs(ref.max() - real)) # joint chooses the most likely realization of the tree assert (abs(ref.max() - real) < 1e-10) return ref, real
def mugration_inference(tree=None, seq_meta=None, field='country', confidence=True, infer_gtr=True, root_state=None, missing='?'): from treetime import GTR from Bio.Align import MultipleSeqAlignment from Bio.SeqRecord import SeqRecord from Bio.Seq import Seq from Bio import Phylo T = Phylo.read(tree, 'newick') nodes = {n.name:n for n in T.get_terminals()} # Determine alphabet only counting tips in the tree places = set() for name, meta in seq_meta.items(): if field in meta and name in nodes: places.add(meta[field]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc>180: print("ERROR: geo_inference: can't have more than 180 places!", file=sys.stderr) return None,None elif nc==1: print("WARNING: geo_inference: only one place found -- set every internal node to %s!"%places[0], file=sys.stderr) return None,None elif nc==0: print("ERROR: geo_inference: list of places is empty!", file=sys.stderr) return None,None else: # set up model alphabet = {chr(65+i):place for i,place in enumerate(places)} model = GTR.custom(pi = np.ones(nc, dtype=float)/nc, W=np.ones((nc,nc)), alphabet = np.array(sorted(alphabet.keys()))) missing_char = chr(65+nc) alphabet[missing_char]=missing model.profile_map[missing_char] = np.ones(nc) model.ambiguous = missing_char alphabet_rev = {v:k for k,v in alphabet.items()} # construct pseudo alignment pseudo_seqs = [] for name, meta in seq_meta.items(): if name in nodes: s=alphabet_rev[meta[field]] if field in meta else missing_char pseudo_seqs.append(SeqRecord(Seq(s), name=name, id=name)) aln = MultipleSeqAlignment(pseudo_seqs) # set up treetime and infer from treetime import TreeAnc tt = TreeAnc(tree=tree, aln=aln, gtr=model, convert_upper=False, verbose=0) tt.use_mutation_length=False tt.infer_ancestral_sequences(infer_gtr=infer_gtr, store_compressed=False, pc=5.0, marginal=True, normalized_rate=False) # attach inferred states as e.g. node.region = 'africa' for node in tt.tree.find_clades(): node.__setattr__(field, alphabet[node.sequence[0]]) # if desired, attach entropy and confidence as e.g. node.region_entropy = 0.03 if confidence: for node in tt.tree.find_clades(): pdis = node.marginal_profile[0] S = -np.sum(pdis*np.log(pdis+TINY)) marginal = [(alphabet[tt.gtr.alphabet[i]], pdis[i]) for i in range(len(tt.gtr.alphabet))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.001][:4] #only take stuff over .1% and the top 4 elements conf = {a:b for a,b in marginal} node.__setattr__(field + "_entropy", S) node.__setattr__(field + "_confidence", conf) return tt, alphabet
sep='\t' if params.states[-3:] == 'tsv' else ',', skipinitialspace=True) weights = {row[0]: row[1] for ri, row in tmp_weights.iterrows()} mean_weight = np.mean(weights.values()) weights = np.array([ weights[c] if c in weights else mean_weight for c in unique_states ], dtype=float) weights /= weights.sum() else: weights = np.ones(nc, dtype=float) / nc # set up dummy matrix W = np.ones((nc, nc), dtype=float) mugration_GTR = GTR.custom(pi=weights, W=W, alphabet=np.array(alphabet)) mugration_GTR.profile_map[missing_char] = np.ones(nc) mugration_GTR.ambiguous = missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(params.tree, gtr=mugration_GTR, verbose=params.verbose) pseudo_seqs = [ SeqRecord(id=n.name, name=n.name, seq=Seq(reverse_alphabet[leaf_to_attr[n.name]] if n.name in leaf_to_attr else missing)) for n in treeanc.tree.get_terminals() ] treeanc.aln = MultipleSeqAlignment(pseudo_seqs)
def reconstruct_discrete_traits(tree, traits, missing_data='?', pc=1.0, sampling_bias_correction=None, weights=None, verbose=0, iterations=5): """take a set of discrete states associated with tips of a tree and reconstruct their ancestral states along with a GTR model that approximately maximizes the likelihood of the states on the tree. Parameters ---------- tree : str, Bio.Phylo.Tree name of tree file or Biopython tree object traits : dict dictionary linking tips to straits missing_data : str, optional string indicating missing data pc : float, optional number of pseudo-counts to be used during GTR inference, default 1.0 sampling_bias_correction : float, optional factor to inflate overall switching rate by to counteract sampling bias weights : str, optional name of file with equilibirum frequencies verbose : int, optional level of verbosity in output iterations : int, optional number of times non-linear optimization of overall rate and transmission estimation are iterated Returns ------- tuple tuple of treeanc object, forward and reverse alphabets Raises ------ TreeTimeError raise error if ancestral reconstruction errors out """ ########################################################################### ### make a single character alphabet that maps to discrete states ########################################################################### unique_states = set(traits.values()) n_observed_states = len(unique_states) # load weights from file and convert to dict if supplied as string if type(weights)==str: try: tmp_weights = pd.read_csv(weights, sep='\t' if weights[-3:]=='tsv' else ',', skipinitialspace=True) weight_dict = {row[0]:row[1] for ri,row in tmp_weights.iterrows() if not np.isnan(row[1])} except: raise ValueError("Loading of weights file '%s' failed!"%weights) elif type(weights)==dict: weight_dict = weights else: weight_dict = None # add weights to unique states for alphabet construction if weight_dict is not None: unique_states.update(weight_dict.keys()) missing_weights = [c for c in unique_states if c not in weight_dict and c is not missing_data] if len(missing_weights): print("Missing weights for values: " + ", ".join(missing_weights)) if len(missing_weights)>0.5*n_observed_states: print("More than half of discrete states missing from the weights file") print("Weights read from file are:", weights) raise TreeTimeError("More than half of discrete states missing from the weights file") unique_states=sorted(unique_states) # make a map from states (excluding missing data) to characters in the alphabet # note that gap character '-' is chr(45) and will never be included here reverse_alphabet = {state:chr(65+i) for i,state in enumerate(unique_states) if state!=missing_data} alphabet = list(reverse_alphabet.values()) # construct a look up from alphabet character to states letter_to_state = {v:k for k,v in reverse_alphabet.items()} # construct the vector with weights to be used as equilibrium frequency if weight_dict is not None: mean_weight = np.mean(list(weight_dict.values())) weights = np.array([weight_dict[letter_to_state[c]] if letter_to_state[c] in weight_dict else mean_weight for c in alphabet], dtype=float) weights/=weights.sum() # consistency checks if len(alphabet)<2: print("mugration: only one or zero states found -- this doesn't make any sense", file=sys.stderr) return None, None, None n_states = len(alphabet) missing_char = chr(65+n_states) reverse_alphabet[missing_data]=missing_char letter_to_state[missing_char]=missing_data ########################################################################### ### construct gtr model ########################################################################### # set up dummy matrix W = np.ones((n_states,n_states), dtype=float) mugration_GTR = GTR.custom(pi = weights, W=W, alphabet = np.array(alphabet)) mugration_GTR.profile_map[missing_char] = np.ones(n_states) mugration_GTR.ambiguous=missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(tree, gtr=mugration_GTR, verbose=verbose, convert_upper=False, one_mutation=0.001) treeanc.use_mutation_length = False pseudo_seqs = [SeqRecord(id=n.name,name=n.name, seq=Seq(reverse_alphabet[traits[n.name]] if n.name in traits else missing_char)) for n in treeanc.tree.get_terminals()] valid_seq = np.array([str(s.seq)!=missing_char for s in pseudo_seqs]) print("Assigned discrete traits to %d out of %d taxa.\n"%(np.sum(valid_seq),len(valid_seq))) treeanc.aln = MultipleSeqAlignment(pseudo_seqs) try: ndiff = treeanc.infer_ancestral_sequences(method='ml', infer_gtr=True, store_compressed=False, pc=pc, marginal=True, normalized_rate=False, fixed_pi=weights, reconstruct_tip_states=True) treeanc.optimize_gtr_rate() except TreeTimeError as e: print("\nAncestral reconstruction failed, please see above for error messages and/or rerun with --verbose 4\n") raise e for i in range(iterations): treeanc.infer_gtr(marginal=True, normalized_rate=False, pc=pc, fixed_pi=weights) treeanc.optimize_gtr_rate() if sampling_bias_correction: treeanc.gtr.mu *= sampling_bias_correction treeanc.infer_ancestral_sequences(infer_gtr=False, store_compressed=False, marginal=True, normalized_rate=False, reconstruct_tip_states=True) print(fill("NOTE: previous versions (<0.7.0) of this command made a 'short-branch length assumption. " "TreeTime now optimizes the overall rate numerically and thus allows for long branches " "along which multiple changes accumulated. This is expected to affect estimates of the " "overall rate while leaving the relative rates mostly unchanged.")) return treeanc, letter_to_state, reverse_alphabet
def mugration_inference(tree=None, seq_meta=None, field='country', confidence=True, infer_gtr=True, root_state=None, missing='?', sampling_bias_correction=None): """ Infer likely ancestral states of a discrete character assuming a time reversible model. Parameters ---------- tree : str name of tree file seq_meta : dict meta data associated with sequences field : str, optional meta data field to use confidence : bool, optional calculate confidence values for inferences infer_gtr : bool, optional infer a GTR model for trait transitions (otherwises uses a flat model with rate 1) root_state : None, optional force the state of the root node (currently not implemented) missing : str, optional character that is to be interpreted as missing data, default='?' Returns ------- T : Phylo.Tree Biophyton tree gtr : treetime.GTR GTR model alphabet : dict mapping of character states to """ from treetime import GTR from Bio.Align import MultipleSeqAlignment from Bio.SeqRecord import SeqRecord from Bio.Seq import Seq from Bio import Phylo T = Phylo.read(tree, 'newick') nodes = {n.name: n for n in T.get_terminals()} # Determine alphabet only counting tips in the tree places = set() for name, meta in seq_meta.items(): if field in meta and name in nodes: places.add(meta[field]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc > 180: print("ERROR: geo_inference: can't have more than 180 places!", file=sys.stderr) return None, None, None elif nc == 0: print("ERROR: geo_inference: list of places is empty!", file=sys.stderr) return None, None, None elif nc == 1: print( "WARNING: geo_inference: only one place found -- set every internal node to %s!" % places[0], file=sys.stderr) alphabet = {'A': places[0]} alphabet_values = ['A'] gtr = None for node in T.find_clades(): node.sequence = ['A'] node.marginal_profile = np.array([[1.0]]) else: # set up model alphabet = {chr(65 + i): place for i, place in enumerate(places)} model = GTR.custom(pi=np.ones(nc, dtype=float) / nc, W=np.ones((nc, nc)), alphabet=np.array(sorted(alphabet.keys()))) missing_char = chr(65 + nc) alphabet[missing_char] = missing model.profile_map[missing_char] = np.ones(nc) model.ambiguous = missing_char alphabet_rev = {v: k for k, v in alphabet.items()} # construct pseudo alignment pseudo_seqs = [] for name, meta in seq_meta.items(): if name in nodes: s = alphabet_rev[ meta[field]] if field in meta else missing_char pseudo_seqs.append(SeqRecord(Seq(s), name=name, id=name)) aln = MultipleSeqAlignment(pseudo_seqs) # set up treetime and infer from treetime import TreeAnc tt = TreeAnc(tree=tree, aln=aln, gtr=model, convert_upper=False, verbose=0) tt.use_mutation_length = False tt.infer_ancestral_sequences(infer_gtr=infer_gtr, store_compressed=False, pc=1.0, marginal=True, normalized_rate=False) if sampling_bias_correction: tt.gtr.mu *= sampling_bias_correction tt.infer_ancestral_sequences(infer_gtr=False, store_compressed=False, marginal=True, normalized_rate=False) T = tt.tree gtr = tt.gtr alphabet_values = tt.gtr.alphabet # attach inferred states as e.g. node.region = 'africa' for node in T.find_clades(): node.__setattr__(field, alphabet[node.sequence[0]]) # if desired, attach entropy and confidence as e.g. node.region_entropy = 0.03 if confidence: for node in T.find_clades(): pdis = node.marginal_profile[0] S = -np.sum(pdis * np.log(pdis + TINY)) marginal = [(alphabet[alphabet_values[i]], pdis[i]) for i in range(len(alphabet_values))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.001 ][:4] #only take stuff over .1% and the top 4 elements conf = {a: b for a, b in marginal} node.__setattr__(field + "_entropy", S) node.__setattr__(field + "_confidence", conf) return T, gtr, alphabet
def mugration_inference(tree=None, seq_meta=None, field='country', confidence=True, infer_gtr=True, root_state=None, missing='?'): from treetime import GTR from Bio.Align import MultipleSeqAlignment from Bio.SeqRecord import SeqRecord from Bio.Seq import Seq # Determine alphabet places = set() for meta in seq_meta.values(): if field in meta: places.add(meta[field]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc>180: print("geo_inference: can't have more than 180 places!") return None elif nc==1: print("geo_inference: only one place found -- set every internal node to %s!"%places[0]) return None elif nc==0: print("geo_inference: list of places is empty!") return None else: alphabet = {chr(65+i):place for i,place in enumerate(places)} myGeoGTR = GTR.custom(pi = np.ones(nc, dtype=float)/nc, W=np.ones((nc,nc)), alphabet = np.array(sorted(alphabet.keys()))) missing_char = chr(65+nc) alphabet[missing_char]=missing myGeoGTR.profile_map[missing_char] = np.ones(nc) alphabet_rev = {v:k for k,v in alphabet.iteritems()} pseudo_seqs = [] for name, meta in seq_meta.items(): s=alphabet_rev[meta[field]] if field in meta else missing_char pseudo_seqs.append(SeqRecord(Seq(s), name=name, id=name)) aln = MultipleSeqAlignment(pseudo_seqs) from treetime import TreeAnc tt = TreeAnc(tree=tree, aln=aln, gtr=myGeoGTR, convert_upper=False) tt.use_mutation_length=False tt.infer_ancestral_sequences(infer_gtr=infer_gtr, store_compressed=False, pc=5.0, marginal=True, normalized_rate=False) for node in tt.tree.find_clades(): node.__setattr__(field, alphabet[node.sequence[0]]) if confidence: for node in tt.tree.find_clades(): pdis = node.marginal_profile[0] S = -np.sum(pdis*np.log(pdis+TINY)) marginal = [(alphabet[tt.gtr.alphabet[i]], pdis[i]) for i in range(len(tt.gtr.alphabet))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.01][:4] #only take stuff over 1% and the top 4 elements conf = {a:b for a,b in marginal} node.__setattr__(field + "_entropy", S) node.__setattr__(field + "_confidence", conf) return tt, alphabet
def mugration_inference(tree=None, seq_meta=None, field='country', confidence=True, infer_gtr=True, root_state=None, missing='?', sampling_bias_correction=None): """ Infer likely ancestral states of a discrete character assuming a time reversible model. Parameters ---------- tree : str name of tree file seq_meta : dict meta data associated with sequences field : str, optional meta data field to use confidence : bool, optional calculate confidence values for inferences infer_gtr : bool, optional infer a GTR model for trait transitions (otherwises uses a flat model with rate 1) root_state : None, optional force the state of the root node (currently not implemented) missing : str, optional character that is to be interpreted as missing data, default='?' Returns ------- T : Phylo.Tree Biophyton tree gtr : treetime.GTR GTR model alphabet : dict mapping of character states to """ from treetime import GTR from Bio.Align import MultipleSeqAlignment from Bio.SeqRecord import SeqRecord from Bio.Seq import Seq from Bio import Phylo T = Phylo.read(tree, 'newick') nodes = {n.name:n for n in T.get_terminals()} # Determine alphabet only counting tips in the tree places = set() for name, meta in seq_meta.items(): if field in meta and name in nodes: places.add(meta[field]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc>180: print("ERROR: geo_inference: can't have more than 180 places!", file=sys.stderr) return None,None,None elif nc==0: print("ERROR: geo_inference: list of places is empty!", file=sys.stderr) return None,None,None elif nc==1: print("WARNING: geo_inference: only one place found -- set every internal node to %s!"%places[0], file=sys.stderr) alphabet = {'A':places[0]} alphabet_values = ['A'] gtr = None for node in T.find_clades(): node.sequence=['A'] node.marginal_profile=np.array([[1.0]]) else: # set up model alphabet = {chr(65+i):place for i,place in enumerate(places)} model = GTR.custom(pi = np.ones(nc, dtype=float)/nc, W=np.ones((nc,nc)), alphabet = np.array(sorted(alphabet.keys()))) missing_char = chr(65+nc) alphabet[missing_char]=missing model.profile_map[missing_char] = np.ones(nc) model.ambiguous = missing_char alphabet_rev = {v:k for k,v in alphabet.items()} # construct pseudo alignment pseudo_seqs = [] for name, meta in seq_meta.items(): if name in nodes: s=alphabet_rev[meta[field]] if field in meta else missing_char pseudo_seqs.append(SeqRecord(Seq(s), name=name, id=name)) aln = MultipleSeqAlignment(pseudo_seqs) # set up treetime and infer from treetime import TreeAnc tt = TreeAnc(tree=tree, aln=aln, gtr=model, convert_upper=False, verbose=0) tt.use_mutation_length = False tt.infer_ancestral_sequences(infer_gtr=infer_gtr, store_compressed=False, pc=1.0, marginal=True, normalized_rate=False) if sampling_bias_correction: tt.gtr.mu *= sampling_bias_correction tt.infer_ancestral_sequences(infer_gtr=False, store_compressed=False, marginal=True, normalized_rate=False) T = tt.tree gtr = tt.gtr alphabet_values = tt.gtr.alphabet # attach inferred states as e.g. node.region = 'africa' for node in T.find_clades(): node.__setattr__(field, alphabet[node.sequence[0]]) # if desired, attach entropy and confidence as e.g. node.region_entropy = 0.03 if confidence: for node in T.find_clades(): pdis = node.marginal_profile[0] S = -np.sum(pdis*np.log(pdis+TINY)) marginal = [(alphabet[alphabet_values[i]], pdis[i]) for i in range(len(alphabet_values))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.001][:4] #only take stuff over .1% and the top 4 elements conf = {a:b for a,b in marginal} node.__setattr__(field + "_entropy", S) node.__setattr__(field + "_confidence", conf) return T, gtr, alphabet
def mugration(params): """ implementing treetime mugration """ ########################################################################### ### Parse states ########################################################################### if os.path.isfile(params.states): states = pd.read_csv(params.states, sep='\t' if params.states[-3:]=='tsv' else ',', skipinitialspace=True) else: print("file with states does not exist") return 1 outdir = get_outdir(params, '_mugration') taxon_name = 'name' if 'name' in states.columns else states.columns[0] if params.attribute: if params.attribute in states.columns: attr = params.attribute else: print("The specified attribute was not found in the metadata file "+params.states, file=sys.stderr) print("Available columns are: "+", ".join(states.columns), file=sys.stderr) return 1 else: attr = states.columns[1] print("Attribute for mugration inference was not specified. Using "+attr, file=sys.stderr) leaf_to_attr = {x[taxon_name]:x[attr] for xi, x in states.iterrows() if x[attr]!=params.missing_data} unique_states = sorted(set(leaf_to_attr.values())) nc = len(unique_states) if nc>180: print("mugration: can't have more than 180 states!", file=sys.stderr) return 1 elif nc<2: print("mugration: only one or zero states found -- this doesn't make any sense", file=sys.stderr) return 1 ########################################################################### ### make a single character alphabet that maps to discrete states ########################################################################### alphabet = [chr(65+i) for i,state in enumerate(unique_states)] missing_char = chr(65+nc) letter_to_state = {a:unique_states[i] for i,a in enumerate(alphabet)} letter_to_state[missing_char]=params.missing_data reverse_alphabet = {v:k for k,v in letter_to_state.items()} ########################################################################### ### construct gtr model ########################################################################### if params.weights: params.infer_gtr = True tmp_weights = pd.read_csv(params.weights, sep='\t' if params.states[-3:]=='tsv' else ',', skipinitialspace=True) weights = {row[0]:row[1] for ri,row in tmp_weights.iterrows()} mean_weight = np.mean(list(weights.values())) weights = np.array([weights[c] if c in weights else mean_weight for c in unique_states], dtype=float) weights/=weights.sum() else: weights = np.ones(nc, dtype=float)/nc # set up dummy matrix W = np.ones((nc,nc), dtype=float) mugration_GTR = GTR.custom(pi = weights, W=W, alphabet = np.array(alphabet)) mugration_GTR.profile_map[missing_char] = np.ones(nc) mugration_GTR.ambiguous=missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(params.tree, gtr=mugration_GTR, verbose=params.verbose, convert_upper=False, one_mutation=0.001) pseudo_seqs = [SeqRecord(id=n.name,name=n.name, seq=Seq(reverse_alphabet[leaf_to_attr[n.name]] if n.name in leaf_to_attr else missing_char)) for n in treeanc.tree.get_terminals()] treeanc.aln = MultipleSeqAlignment(pseudo_seqs) ndiff = treeanc.infer_ancestral_sequences(method='ml', infer_gtr=True, store_compressed=False, pc=params.pc, marginal=True, normalized_rate=False, fixed_pi=weights if params.weights else None) if ndiff==ttconf.ERROR: # if reconstruction failed, exit return 1 ########################################################################### ### output ########################################################################### print("\nCompleted mugration model inference of attribute '%s' for"%attr,params.tree) basename = get_basename(params, outdir) gtr_name = basename + 'GTR.txt' with open(gtr_name, 'w') as ofile: ofile.write('Character to attribute mapping:\n') for state in unique_states: ofile.write(' %s: %s\n'%(reverse_alphabet[state], state)) ofile.write('\n\n'+str(treeanc.gtr)+'\n') print("\nSaved inferred mugration model as:", gtr_name) terminal_count = 0 for n in treeanc.tree.find_clades(): if n.up is None: continue n.confidence=None # due to a bug in older versions of biopython that truncated filenames in nexus export # we truncate them by hand and make them unique. if n.is_terminal() and len(n.name)>40 and bioversion<"1.69": n.name = n.name[:35]+'_%03d'%terminal_count terminal_count+=1 n.comment= '&%s="'%attr + letter_to_state[n.sequence[0]] +'"' if params.confidence: conf_name = basename+'confidence.csv' with open(conf_name, 'w') as ofile: ofile.write('#name, '+', '.join(unique_states)+'\n') for n in treeanc.tree.find_clades(): ofile.write(n.name + ', '+', '.join([str(x) for x in n.marginal_profile[0]])+'\n') print("Saved table with ancestral state confidences as:", conf_name) # write tree to file outtree_name = basename+'annotated_tree.nexus' Phylo.write(treeanc.tree, outtree_name, 'nexus') print("Saved annotated tree as:",outtree_name) return 0
def moogration(params): """ implementing treetime moogration """ ########################################################################### ### Parse states ########################################################################### if os.path.isfile(params.states): states = pd.read_csv(params.states, sep='\t' if params.states[-3:] == 'tsv' else ',', skipinitialspace=True) else: print("file with states does not exist") return 1 outdir = get_outdir(params, '_moogration') taxon_name = 'name' if 'name' in states.columns else states.columns[0] if params.attribute: if params.attribute in states.columns: attr = params.attribute else: print( "The specified attribute was not found in the metadata file " + params.states, file=sys.stderr) print("Available columns are: " + ", ".join(states.columns), file=sys.stderr) return 1 else: attr = states.columns[1] print("Attribute for moogration inference was not specified. Using " + attr, file=sys.stderr) leaf_to_attr = { x[taxon_name]: x[attr] for xi, x in states.iterrows() if x[attr] != params.missing_data } unique_states = sorted(set(leaf_to_attr.values())) nc = len(unique_states) if nc > 180: print("moogration: can't have more than 180 states!", file=sys.stderr) return 1 elif nc < 2: print( "moogration: only one or zero states found -- this doesn't make any sense", file=sys.stderr) return 1 ########################################################################### ### make a single character alphabet that maps to discrete states ########################################################################### alphabet = [chr(65 + i) for i, state in enumerate(unique_states)] missing_char = chr(65 + nc) letter_to_state = {a: unique_states[i] for i, a in enumerate(alphabet)} letter_to_state[missing_char] = params.missing_data reverse_alphabet = {v: k for k, v in letter_to_state.items()} ########################################################################### ### construct gtr model ########################################################################### if params.weights: params.infer_gtr = True tmp_weights = pd.read_csv( params.weights, sep='\t' if params.states[-3:] == 'tsv' else ',', skipinitialspace=True) weights = {row[0]: row[1] for ri, row in tmp_weights.iterrows()} mean_weight = np.mean(list(weights.values())) weights = np.array([ weights[c] if c in weights else mean_weight for c in unique_states ], dtype=float) weights /= weights.sum() else: weights = np.ones(nc, dtype=float) / nc # set up dummy matrix W = np.ones((nc, nc), dtype=float) moogration_GTR = GTR.custom(pi=weights, W=W, alphabet=np.array(alphabet)) moogration_GTR.profile_map[missing_char] = np.ones(nc) moogration_GTR.ambiguous = missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(params.tree, gtr=moogration_GTR, verbose=params.verbose, convert_upper=False, one_mutation=0.001) pseudo_seqs = [ SeqRecord(id=n.name, name=n.name, seq=Seq(reverse_alphabet[leaf_to_attr[n.name]] if n.name in leaf_to_attr else missing_char)) for n in treeanc.tree.get_terminals() ] treeanc.aln = MultipleSeqAlignment(pseudo_seqs) ndiff = treeanc.infer_ancestral_sequences( method='ml', infer_gtr=True, store_compressed=False, pc=params.pc, marginal=True, normalized_rate=False, fixed_pi=weights if params.weights else None) if ndiff == ttconf.ERROR: # if reconstruction failed, exit return 1 ########################################################################### ### output ########################################################################### print( "\nCompleted moogration model inference of attribute '%s' for" % attr, params.tree) basename = get_basename(params, outdir) gtr_name = basename + 'GTR.txt' with open(gtr_name, 'w') as ofile: ofile.write('Character to attribute mapping:\n') for state in unique_states: ofile.write(' %s: %s\n' % (reverse_alphabet[state], state)) ofile.write('\n\n' + str(treeanc.gtr) + '\n') print("\nSaved inferred moogration model as:", gtr_name) terminal_count = 0 for n in treeanc.tree.find_clades(): if n.up is None: continue n.confidence = None # due to a bug in older versions of biopython that truncated filenames in nexus export # we truncate them by hand and make them unique. if n.is_terminal() and len(n.name) > 40 and bioversion < "1.69": n.name = n.name[:35] + '_%03d' % terminal_count terminal_count += 1 n.comment = '&%s="' % attr + letter_to_state[n.sequence[0]] + '"' if params.confidence: conf_name = basename + 'confidence.csv' with open(conf_name, 'w') as ofile: ofile.write('#name, ' + ', '.join(unique_states) + '\n') for n in treeanc.tree.find_clades(): ofile.write(n.name + ', ' + ', '.join([str(x) for x in n.marginal_profile[0]]) + '\n') print("Saved table with ancestral state confidences as:", conf_name) # write tree to file outtree_name = basename + 'annotated_tree.nexus' Phylo.write(treeanc.tree, outtree_name, 'nexus') print("Saved annotated tree as:", outtree_name) return 0
def geo_inference(self, attr, missing='?', root_state=None, report_confidence=False): ''' infer a "mugration" model by pretending each region corresponds to a sequence state and repurposing the GTR inference and ancestral reconstruction ''' from treetime import GTR # Determine alphabet places = set() for node in self.tree.find_clades(): if hasattr(node, 'attr'): if attr in node.attr and attr!=missing: places.add(node.attr[attr]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc>180: self.logger("geo_inference: can't have more than 180 places!",1) return elif nc==1: self.logger("geo_inference: only one place found -- setting every internal node to %s!"%places[0],1) for node in self.tree.find_clades(): node.attr[attr] = places[0] node.__setattr__(attr+'_transitions',[]) return elif nc==0: self.logger("geo_inference: list of places is empty!",1) return # store previously reconstructed sequences nuc_seqs = {} nuc_muts = {} nuc_seq_LH = None if hasattr(self.tt.tree,'sequence_LH'): nuc_seq_LH = self.tt.tree.sequence_LH for node in self.tree.find_clades(): if hasattr(node, 'sequence'): nuc_seqs[node] = node.sequence if hasattr(node, 'mutations'): nuc_muts[node] = node.mutations node.__delattr__('mutations') alphabet = {chr(65+i):place for i,place in enumerate(places)} sequence_gtr = self.tt.gtr myGeoGTR = GTR.custom(pi = np.ones(nc, dtype=float)/nc, W=np.ones((nc,nc)), alphabet = np.array(sorted(alphabet.keys()))) missing_char = chr(65+nc) alphabet[missing_char]=missing myGeoGTR.profile_map[missing_char] = np.ones(nc) alphabet_rev = {v:k for k,v in alphabet.items()} # set geo info to nodes as one letter sequence. self.tt.seq_len = 1 for node in self.tree.get_terminals(): if hasattr(node, 'attr'): if attr in node.attr: node.sequence=np.array([alphabet_rev[node.attr[attr]]]) else: node.sequence=np.array([missing_char]) else: node.sequence=np.array([missing_char]) for node in self.tree.get_nonterminals(): node.__delattr__('sequence') if root_state is not None: self.tree.root.split(n=1, branch_length=0.0) extra_clade = self.tree.root.clades[-1] extra_clade.name = "dummy_root_node" extra_clade.up = self.tree.root extra_clade.sequence = np.array([alphabet_rev[root_state]]) self.tt.make_reduced_alignment() # set custom GTR model, run inference self.tt._gtr = myGeoGTR # import pdb; pdb.set_trace() tmp_use_mutation_length = self.tt.use_mutation_length self.tt.use_mutation_length=False self.tt.infer_ancestral_sequences(method='ml', infer_gtr=False, store_compressed=False, pc=5.0, marginal=True, normalized_rate=False) if root_state is not None: self.tree.prune(extra_clade) # restore the nucleotide sequence and mutations to maintain expected behavior self.tt.geogtr = self.tt.gtr self.tt.geogtr.alphabet_to_location = alphabet self.tt._gtr = sequence_gtr if hasattr(self.tt.tree,'sequence_LH'): self.tt.tree.geo_LH = self.tt.tree.sequence_LH self.tt.tree.sequence_LH = nuc_seq_LH for node in self.tree.find_clades(): node.attr[attr] = alphabet[node.sequence[0]] if node in nuc_seqs: node.sequence = nuc_seqs[node] if node.up is not None: node.__setattr__(attr+'_transitions', node.mutations) if node in nuc_muts: node.mutations = nuc_muts[node] # save marginal likelihoods if desired if report_confidence: node.attr[attr + "_entropy"] = sum([v * math.log(v+1E-20) for v in node.marginal_profile[0]]) * -1 / math.log(len(node.marginal_profile[0])) # javascript: vals.map((v) => v * Math.log(v + 1E-10)).reduce((a, b) => a + b, 0) * -1 / Math.log(vals.length); marginal = [(alphabet[self.tt.geogtr.alphabet[i]], node.marginal_profile[0][i]) for i in range(0, len(self.tt.geogtr.alphabet))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.01][:4] #only take stuff over 1% and the top 4 elements node.attr[attr + "_confidence"] = {a:b for a,b in marginal} self.tt.use_mutation_length=tmp_use_mutation_length # store saved attrs for save/restore functionality if not hasattr(self, "mugration_attrs"): self.mugration_attrs = [] self.mugration_attrs.append(attr) if report_confidence: self.mugration_attrs.extend([attr + "_entropy", attr + "_confidence"])
def geo_inference(self, attr, missing='?', root_state=None, report_confidence=False): ''' infer a "mugration" model by pretending each region corresponds to a sequence state and repurposing the GTR inference and ancestral reconstruction ''' from treetime import GTR # Determine alphabet places = set() for node in self.tree.find_clades(): if hasattr(node, 'attr'): if attr in node.attr and attr!=missing: places.add(node.attr[attr]) if root_state is not None: places.add(root_state) # construct GTR (flat for now). The missing DATA symbol is a '-' (ord('-')==45) places = sorted(places) nc = len(places) if nc>180: self.logger("geo_inference: can't have more than 180 places!",1) return elif nc==1: self.logger("geo_inference: only one place found -- setting every internal node to %s!"%places[0],1) for node in self.tree.find_clades(): node.attr[attr] = places[0] node.__setattr__(attr+'_transitions',[]) return elif nc==0: self.logger("geo_inference: list of places is empty!",1) return # store previously reconstructed sequences nuc_seqs = {} nuc_muts = {} nuc_seq_LH = None if hasattr(self.tt.tree,'sequence_LH'): nuc_seq_LH = self.tt.tree.sequence_LH for node in self.tree.find_clades(): if hasattr(node, 'sequence'): nuc_seqs[node] = node.sequence if hasattr(node, 'mutations'): nuc_muts[node] = node.mutations node.__delattr__('mutations') alphabet = {chr(65+i):place for i,place in enumerate(places)} sequence_gtr = self.tt.gtr myGeoGTR = GTR.custom(pi = np.ones(nc, dtype=float)/nc, W=np.ones((nc,nc)), alphabet = np.array(sorted(alphabet.keys()))) missing_char = chr(65+nc) alphabet[missing_char]=missing myGeoGTR.profile_map[missing_char] = np.ones(nc) alphabet_rev = {v:k for k,v in alphabet.iteritems()} # set geo info to nodes as one letter sequence. self.tt.seq_len = 1 for node in self.tree.get_terminals(): if hasattr(node, 'attr'): if attr in node.attr: node.sequence=np.array([alphabet_rev[node.attr[attr]]]) else: node.sequence=np.array([missing_char]) else: node.sequence=np.array([missing_char]) for node in self.tree.get_nonterminals(): node.__delattr__('sequence') if root_state is not None: self.tree.root.split(n=1, branch_length=0.0) extra_clade = self.tree.root.clades[-1] extra_clade.name = "dummy_root_node" extra_clade.up = self.tree.root extra_clade.sequence = np.array([alphabet_rev[root_state]]) self.tt.make_reduced_alignment() # set custom GTR model, run inference self.tt._gtr = myGeoGTR # import pdb; pdb.set_trace() tmp_use_mutation_length = self.tt.use_mutation_length self.tt.use_mutation_length=False self.tt.infer_ancestral_sequences(method='ml', infer_gtr=False, store_compressed=False, pc=5.0, marginal=True, normalized_rate=False) if root_state is not None: self.tree.prune(extra_clade) # restore the nucleotide sequence and mutations to maintain expected behavior self.tt.geogtr = self.tt.gtr self.tt.geogtr.alphabet_to_location = alphabet self.tt._gtr = sequence_gtr if hasattr(self.tt.tree,'sequence_LH'): self.tt.tree.geo_LH = self.tt.tree.sequence_LH self.tt.tree.sequence_LH = nuc_seq_LH for node in self.tree.find_clades(): node.attr[attr] = alphabet[node.sequence[0]] if node in nuc_seqs: node.sequence = nuc_seqs[node] if node.up is not None: node.__setattr__(attr+'_transitions', node.mutations) if node in nuc_muts: node.mutations = nuc_muts[node] # save marginal likelihoods if desired if report_confidence: node.attr[attr + "_entropy"] = sum([v * math.log(v+1E-20) for v in node.marginal_profile[0]]) * -1 / math.log(len(node.marginal_profile[0])) # javascript: vals.map((v) => v * Math.log(v + 1E-10)).reduce((a, b) => a + b, 0) * -1 / Math.log(vals.length); marginal = [(alphabet[self.tt.geogtr.alphabet[i]], node.marginal_profile[0][i]) for i in range(0, len(self.tt.geogtr.alphabet))] marginal.sort(key=lambda x: x[1], reverse=True) # sort on likelihoods marginal = [(a, b) for a, b in marginal if b > 0.01][:4] #only take stuff over 1% and the top 4 elements node.attr[attr + "_confidence"] = {a:b for a,b in marginal} self.tt.use_mutation_length=tmp_use_mutation_length # store saved attrs for save/restore functionality if not hasattr(self, "mugration_attrs"): self.mugration_attrs = [] self.mugration_attrs.append(attr) if report_confidence: self.mugration_attrs.extend([attr + "_entropy", attr + "_confidence"])
def test_seq_joint_reconstruction_correct(): """ evolve the random sequence, get the alignment at the leaf nodes. Reconstruct the sequences of the internal nodes (joint) and prove the reconstruction is correct. In addition, compute the likelihood of the particular realization of the sequences on the tree and prove that this likelihood is exactly the same as calculated in the joint reconstruction """ from treetime import TreeAnc, GTR from treetime import seq_utils from Bio import Phylo, AlignIO import numpy as np try: from itertools import izip except ImportError: #python3.x izip = zip from collections import defaultdict def exclusion(a, b): """ Intersection of two lists """ return list(set(a) - set(b)) tiny_tree = Phylo.read(StringIO("((A:.060,B:.01200)C:.020,D:.0050)E:.004;"), 'newick') mygtr = GTR.custom(alphabet = np.array(['A', 'C', 'G', 'T']), pi = np.array([0.15, 0.95, 0.05, 0.3]), W=np.ones((4,4))) seq = np.random.choice(mygtr.alphabet, p=mygtr.Pi, size=400) myTree = TreeAnc(gtr=mygtr, tree=tiny_tree, aln=None, verbose=4) # simulate evolution, set resulting sequence as ref_seq tree = myTree.tree seq_len = 400 tree.root.ref_seq = np.random.choice(mygtr.alphabet, p=mygtr.Pi, size=seq_len) print ("Root sequence: " + ''.join(tree.root.ref_seq)) mutation_list = defaultdict(list) for node in tree.find_clades(): for c in node.clades: c.up = node if hasattr(node, 'ref_seq'): continue t = node.branch_length p = mygtr.propagate_profile( seq_utils.seq2prof(node.up.ref_seq, mygtr.profile_map), t) # normalie profile p=(p.T/p.sum(axis=1)).T # sample mutations randomly ref_seq_idxs = np.array([int(np.random.choice(np.arange(p.shape[1]), p=p[k])) for k in np.arange(p.shape[0])]) node.ref_seq = np.array([mygtr.alphabet[k] for k in ref_seq_idxs]) node.ref_mutations = [(anc, pos, der) for pos, (anc, der) in enumerate(izip(node.up.ref_seq, node.ref_seq)) if anc!=der] for anc, pos, der in node.ref_mutations: print(pos) mutation_list[pos].append((node.name, anc, der)) print (node.name, len(node.ref_mutations), node.ref_mutations) # set as the starting sequences to the terminal nodes: alnstr = "" i = 1 for leaf in tree.get_terminals(): alnstr += ">" + leaf.name + "\n" + ''.join(leaf.ref_seq) + '\n' i += 1 print (alnstr) myTree.aln = AlignIO.read(StringIO(alnstr), 'fasta') myTree._attach_sequences_to_nodes() # reconstruct ancestral sequences: myTree._ml_anc_joint(debug=True) diff_count = 0 mut_count = 0 for node in myTree.tree.find_clades(): if node.up is not None: mut_count += len(node.ref_mutations) diff_count += np.sum(node.sequence != node.ref_seq)==0 if np.sum(node.sequence != node.ref_seq): print("%s: True sequence does not equal inferred sequence. parent %s"%(node.name, node.up.name)) else: print("%s: True sequence equals inferred sequence. parent %s"%(node.name, node.up.name)) print (node.name, np.sum(node.sequence != node.ref_seq), np.where(node.sequence != node.ref_seq), len(node.mutations), node.mutations) # the assignment of mutations to the root node is probabilistic. Hence some differences are expected assert diff_count/seq_len<2*(1.0*mut_count/seq_len)**2 # prove the likelihood value calculation is correct LH = myTree.ancestral_likelihood() LH_p = (myTree.tree.sequence_LH) print ("Difference between reference and inferred LH:", (LH - LH_p).sum()) assert ((LH - LH_p).sum())<1e-9 return myTree
def reconstruct_discrete_traits(tree, traits, missing_data='?', pc=1.0, sampling_bias_correction=None, weights=None, verbose=0, iterations=5): """take a set of discrete states associated with tips of a tree and reconstruct their ancestral states along with a GTR model that approximately maximizes the likelihood of the states on the tree. Parameters ---------- tree : str, Bio.Phylo.Tree name of tree file or Biopython tree object traits : dict dictionary linking tips to straits missing_data : str, optional string indicating missing data pc : float, optional number of pseudo-counts to be used during GTR inference, default 1.0 sampling_bias_correction : float, optional factor to inflate overall switching rate by to counteract sampling bias weights : str, optional name of file with equilibirum frequencies verbose : int, optional level of verbosity in output iterations : int, optional number of times non-linear optimization of overall rate and transmission estimation are iterated Returns ------- tuple tuple of treeanc object, forward and reverse alphabets Raises ------ TreeTimeError raise error if ancestral reconstruction errors out """ unique_states = sorted(set(traits.values())) nc = len(unique_states) if nc>180: print("mugration: can't have more than 180 states!", file=sys.stderr) return None, None, None elif nc<2: print("mugration: only one or zero states found -- this doesn't make any sense", file=sys.stderr) return None, None, None ########################################################################### ### make a single character alphabet that maps to discrete states ########################################################################### alphabet = [chr(65+i) for i,state in enumerate(unique_states)] missing_char = chr(65+nc) letter_to_state = {a:unique_states[i] for i,a in enumerate(alphabet)} letter_to_state[missing_char]=missing_data reverse_alphabet = {v:k for k,v in letter_to_state.items()} ########################################################################### ### construct gtr model ########################################################################### if type(weights)==str: tmp_weights = pd.read_csv(weights, sep='\t' if weights[-3:]=='tsv' else ',', skipinitialspace=True) weights = {row[0]:row[1] for ri,row in tmp_weights.iterrows()} mean_weight = np.mean(list(weights.values())) weights = np.array([weights[c] if c in weights else mean_weight for c in unique_states], dtype=float) weights/=weights.sum() else: weights = None # set up dummy matrix W = np.ones((nc,nc), dtype=float) mugration_GTR = GTR.custom(pi = weights, W=W, alphabet = np.array(alphabet)) mugration_GTR.profile_map[missing_char] = np.ones(nc) mugration_GTR.ambiguous=missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(tree, gtr=mugration_GTR, verbose=verbose, convert_upper=False, one_mutation=0.001) treeanc.use_mutation_length = False pseudo_seqs = [SeqRecord(id=n.name,name=n.name, seq=Seq(reverse_alphabet[traits[n.name]] if n.name in traits else missing_char)) for n in treeanc.tree.get_terminals()] treeanc.aln = MultipleSeqAlignment(pseudo_seqs) try: ndiff = treeanc.infer_ancestral_sequences(method='ml', infer_gtr=True, store_compressed=False, pc=pc, marginal=True, normalized_rate=False, fixed_pi=weights, reconstruct_tip_states=True) treeanc.optimize_gtr_rate() except TreeTimeError as e: print("\nAncestral reconstruction failed, please see above for error messages and/or rerun with --verbose 4\n") raise e for i in range(iterations): treeanc.infer_gtr(marginal=True, normalized_rate=False, pc=pc) treeanc.optimize_gtr_rate() if sampling_bias_correction: treeanc.gtr.mu *= sampling_bias_correction treeanc.infer_ancestral_sequences(infer_gtr=False, store_compressed=False, marginal=True, normalized_rate=False, reconstruct_tip_states=True) print(fill("NOTE: previous versions (<0.7.0) of this command made a 'short-branch length assumption. " "TreeTime now optimizes the overall rate numerically and thus allows for long branches " "along which multiple changes accumulated. This is expected to affect estimates of the " "overall rate while leaving the relative rates mostly unchanged.")) return treeanc, letter_to_state, reverse_alphabet
if params.tree is None: from treetime.utils import tree_inference params.tree = os.path.basename(params.aln) + '.nwk' print("No tree given: inferring tree") tmp_dir = 'homoplasy_scanner_tmp_files' tree_inference(params.aln, params.tree, tmp_dir=tmp_dir) if os.path.isdir(tmp_dir): shutil.rmtree(tmp_dir) ########################################################################### ### GTR SET-UP ########################################################################### model = params.gtr gtr_params = params.gtr_params if model == 'infer': gtr = GTR.standard('jc') infer_gtr = True else: infer_gtr = False try: kwargs = {} if gtr_params is not None: for param in gtr_params: keyval = param.split('=') if len(keyval) != 2: continue if keyval[0] in ['pis', 'pi', 'Pi', 'Pis']: keyval[1] = map(float, keyval[1].split(',')) elif keyval[0] not in ['alphabet']: keyval[1] = float(keyval[1]) kwargs[keyval[0]] = keyval[1] else:
def reconstruct_discrete_traits(tree, traits, missing_data='?', pc=1.0, sampling_bias_correction=None, weights=None, verbose=0): unique_states = sorted(set(traits.values())) nc = len(unique_states) if nc>180: print("mugration: can't have more than 180 states!", file=sys.stderr) return 1 elif nc<2: print("mugration: only one or zero states found -- this doesn't make any sense", file=sys.stderr) return 1 ########################################################################### ### make a single character alphabet that maps to discrete states ########################################################################### alphabet = [chr(65+i) for i,state in enumerate(unique_states)] missing_char = chr(65+nc) letter_to_state = {a:unique_states[i] for i,a in enumerate(alphabet)} letter_to_state[missing_char]=missing_data reverse_alphabet = {v:k for k,v in letter_to_state.items()} ########################################################################### ### construct gtr model ########################################################################### if type(weights)==str: tmp_weights = pd.read_csv(weights, sep='\t' if weights[-3:]=='tsv' else ',', skipinitialspace=True) weights = {row[0]:row[1] for ri,row in tmp_weights.iterrows()} mean_weight = np.mean(list(weights.values())) weights = np.array([weights[c] if c in weights else mean_weight for c in unique_states], dtype=float) weights/=weights.sum() else: weights = None # set up dummy matrix W = np.ones((nc,nc), dtype=float) mugration_GTR = GTR.custom(pi = weights, W=W, alphabet = np.array(alphabet)) mugration_GTR.profile_map[missing_char] = np.ones(nc) mugration_GTR.ambiguous=missing_char ########################################################################### ### set up treeanc ########################################################################### treeanc = TreeAnc(tree, gtr=mugration_GTR, verbose=verbose, convert_upper=False, one_mutation=0.001) treeanc.use_mutation_length = False pseudo_seqs = [SeqRecord(id=n.name,name=n.name, seq=Seq(reverse_alphabet[traits[n.name]] if n.name in traits else missing_char)) for n in treeanc.tree.get_terminals()] treeanc.aln = MultipleSeqAlignment(pseudo_seqs) ndiff = treeanc.infer_ancestral_sequences(method='ml', infer_gtr=True, store_compressed=False, pc=pc, marginal=True, normalized_rate=False, fixed_pi=weights) if ndiff==ttconf.ERROR: # if reconstruction failed, exit return 1 if sampling_bias_correction: treeanc.gtr.mu *= sampling_bias_correction treeanc.infer_ancestral_sequences(infer_gtr=False, store_compressed=False, marginal=True, normalized_rate=False) return treeanc, letter_to_state, reverse_alphabet