def create_pheno_int_map(phenos, pim_file):
printd('Creating pheno int map...')
with open(phenos, 'r') as f:
line = f.readline() # only need first line which contains headers
pim = {}
for i, p in enumerate(line.split()[1:]): # skip id column
pim[i] = p
pim[p] = i
with open(pim_file, 'wb') as f:
pickle.dump(pim, f)
printd('Successfully created pheno int map.')
def create_kmer_int_map(kmers, kim_file):
printd('Creating kmer int map...')
kim = {}
with open(kmers, 'r') as f:
lines = f.readlines()
for i, line in enumerate(lines):
u = line.split('\t')[0]
kim[u] = i
kim[i] = u
with open(kim_file, 'wb') as f:
pickle.dump(kim, f)
printd('Successfully created kmer int map.')
def sample_kmers(data, n, seed=randint(1, 100000)):
printd('Sampling kmers...')
sample_matrix = np.zeros((n, n))
rng = Random(seed)
num_kmers = int(len(data) * 0.05)
sampled = rng.sample(data, num_kmers)
for line in sampled:
samplelist = line[1:]
for i, s1 in enumerate(samplelist):
for s2 in samplelist[i:]:
sample_matrix[s1[0]][s2[0]] += 1
sample_matrix[s2[0]][s1[0]] += 1
printd('Finished sampling kmers.')
return num_kmers, sample_matrix
def main():
# load params
params = get_params()
project = params['project']
k = params['k']
# define file paths
samples_file = join(project, 'data', 'raw', params['sample'])
outfile = join(project, 'data', 'preprocessed', 'unique_kmers.txt')
catted_samples = join(project, 'data', 'preprocessed', 'samples.fa')
# check if output file exists; if so, do nothing.
if file_exists(outfile):
exit(0)
# create catted samples file if it does not exist.
if not file_exists(catted_samples):
cat_samples(samples_file, catted_samples)
# multiprocessing queue for transferring data to the main thread
q = Manager().Queue()
# invoke process(...) on catted_samples files with kwargs, for each thread
process_file(process, catted_samples, q=q, k=k)
# consolidate all threads' counters into single counter holding all kmers
counter = Counter()
while not q.empty():
counter.update(q.get())
for kmer in counter.keys():
comp = complement(kmer)
if comp in counter:
comp_count = counter[comp]
counter[comp] = 0
counter[kmer] += comp_count
counter = +counter
printd('Finished consolidating counters.')
# write counter to file
write_dict(counter, outfile, sep='\t')
# remove catted samples file
if file_exists(catted_samples):
remove(catted_samples)
def consolidate(data, k):
printd('Consolidating chunk...')
prev_line = data.pop()
prev_unitig = prev_line[0]
unitigs = []
while (data):
line = data.pop()
this_unitig = line[0]
# kmers are sequential and the same set of samples contain both kmers
if prev_unitig[0:k - 1] == this_unitig[-(k - 1):] \
and len(line) == len(prev_line) \
and set(line[1:]) == set(prev_line[1:]):
this_unitig = this_unitig[0] + prev_unitig
line = (this_unitig, *line[1:])
else:
unitigs.append(prev_line)
prev_line = line
prev_unitig = this_unitig
printd('Finished consolidating chunk.')
return unitigs
def filter_kmers(data, thresh, dfdisp, dfnodisp, kmer_sample_file,
kmer_pheno_file, lock):
printd('Filtering kmers...')
nphenos = dfdisp.shape[1]
kmer_samples = []
kmer_phenos = []
while (data):
line = data.pop()
kmer = line[0]
# collect resistant/vulnerable frequencies for each antibiotic for
# this unitig
disp = sum(dfdisp[sample_id[0]] for sample_id in line[1:])
nodisp = sum(dfnodisp[sample_id[0]] for sample_id in line[1:])
# 1 test per antibiotic; unitig needs to pass only 1 to avoid
# getting filtered out
samples_thresh = 5
a = np.where((disp + nodisp >= samples_thresh) \
& (disp / (disp + nodisp + .01) > thresh))[0]
if a.size == 0:
continue
kmer_pheno_chunk = [kmer]
for pheno in a:
kmer_pheno_chunk.append(str(pheno))
kmer_phenos.append('\t'.join(kmer_pheno_chunk))
kmer_samples.append('\t'.join(map(format_tuple, line)))
# write every 500K kmers to keep memory consumption under control
if len(kmer_phenos) >= 500000:
write_files(lock, (kmer_samples, kmer_sample_file),
(kmer_phenos, kmer_pheno_file))
kmer_samples = []
kmer_phenos = []
write_files(lock, (kmer_samples, kmer_sample_file),
(kmer_phenos, kmer_pheno_file))
printd('Finished filtering kmers.')
return
def create_kmer_sample_map(data, raw, q, k, upper, lower, thresh, dfdisp,
dfnodisp, sim, n, lock, kmer_sample_file,
kmer_pheno_file):
printd('Creating kmer sample map...')
# get all kmers in chunk and complement them
kmers = {}
for line in data:
kmer, count = line.split('\t')
if kmer_frequency_fails(count, upper, lower):
continue
kmers[kmer] = Counter()
# map all kmers in chunk to samples containing them
for count, (raw_id, seq) in enumerate(raw.items()):
sample_id = sim.get(raw_id, None)
if sample_id is None:
continue
for c_id, contig in enumerate(seq):
l = len(contig)
if l >= k: # ensure this contig is long enough to sample
for i in range(l - k + 1):
kmer = contig[i:i + k]
kmerlist = kmers.get(kmer, None)
if kmerlist is not None:
kmerlist[sample_id] += 1
else:
complist = kmers.get(complement(kmer), None)
if complist is not None:
complist[sample_id] += 1
kmers = [(key, *v.items()) for key, v in kmers.items()]
printd('Finished creating kmer sample map.')
num_kmers, sample_matrix = sample_kmers(kmers, n)
printd('Putting data in queue')
q.put((num_kmers, sample_matrix))
printd('Finished putting data in queue')
if kmer_sample_file is None and kmer_pheno_file is None:
return
# consolidate() will clear kmers list as it builds unitigs list
# with net 0 memory gain
kmers = consolidate(kmers, k)
# filter_unitigs() will clear unitigs list as it builds new unitigs list
# with net 0 memory gain
filter_kmers(kmers, thresh, dfdisp, dfnodisp, kmer_sample_file,
kmer_pheno_file, lock)
return
def consolidate(name, unitigs, outdir):
unitigs = list(unitigs.iloc[:, 0])
unitigs = [(u, [1/(i+1)]) for i, u in enumerate(unitigs)]
printd('Original num kmers:', len(unitigs))
for k in range(30, 20, -1):
unitigs = consolidate_model(unitigs, k, p=False)
printd(f'K: {k}, num kmers: {len(unitigs)}')
printd('Final num kmers:', len(unitigs))
unitigs = [(unitig, 1 / (sum(ranks) / len(ranks))) for unitig, ranks in unitigs]
unitigs = sorted(unitigs, key=lambda x: x[1])
unitigs = [u[0] for u in unitigs]
write_list(unitigs, join(outdir, name))
def create_sample_int_map(samples, phenos, sim_file):
printd('Creating sample int map...')
sim = {}
with open(samples, 'r') as f:
lines = f.readlines()
phenosdf = pd.read_csv(phenos, sep='\t', index_col=0)
phenosdf.dropna(how='all', inplace=True)
droppedsamples = []
i = 0
for line in lines[1:]: # ignore header
name = line.split('\t')[0]
if name in phenosdf.index:
sim[name] = i
sim[i] = name
i += 1
else:
droppedsamples.append(name)
with open(sim_file, 'wb') as f:
pickle.dump(sim, f)
if len(droppedsamples) > 0:
printd(('Ignoring samples not present in both'
f' sample and pheno files: {droppedsamples}'))
printd('Successfully created sample int map.')
def similar_sample(sample_matrix, num_kmers, similarities_tsv, hist_orig_file,
hist_sim_scaled_file, hist_dissim_scaled_file,
similarities_file, dissimilarities_file):
if not file_exists(similarities_tsv):
# scale similarities matrix by the mean num sampled kmers each sample
# shares with itself. Then, normalize to [0,1]. Then remove the diagonal
# and the lower triangle of the array (since it is symmetric about the
# major diagonal), and finally round values to 4 decimal places.
mean_shared_w_self = sample_matrix.diagonal().mean()
sample_matrix /= mean_shared_w_self
sample_matrix += 0.001 # ensure all values are nonzero
sample_matrix *= 1.0 / sample_matrix.max()
np.fill_diagonal(sample_matrix, np.nan)
sample_matrix = np.triu(sample_matrix)
np.round(sample_matrix, 4)
df = pd.DataFrame(sample_matrix)
# dump to tsv file for ease of restoring, and because tsv file of similarities
# is a common input to other mGWAS programs
df.to_csv(similarities_tsv, sep='\t')
else:
df = pd.read_csv(similarities_tsv, sep='\t', index_col=0)
# create similarity histogram and save it
plt.hist(df.values, facecolor='green')
plt.savefig(hist_orig_file, dpi=150)
plt.clf()
df = df.stack()
df = df.reset_index()
df = df[df[0] > 0] # remove the lower half of the triangle
# set threshold; 0.75 means drop lowest 75%, keep highest 25%
highthresh = 0.9
lowthresh = 0.1
# find numeric cutoff; the lowest 75% of the data are below this value
highcutoff = df[0].quantile(highthresh)
lowcutoff = df[0].quantile(lowthresh)
# cut off all everything in the middle; only keep the very similar and very dissimilar
simdf = df[df[0] >= highcutoff].copy(deep=True)
dissimdf = df[df[0] <= lowcutoff].copy(deep=True)
dissimdf[0] = 1 - dissimdf[0]
dfs = (simdf, dissimdf)
# determine new min, max, range
files = ((hist_sim_scaled_file, similarities_file),
(hist_dissim_scaled_file, dissimilarities_file))
for i, (pngfile, outfile) in enumerate(files):
df = dfs[i]
min_ = df[0].min()
max_ = df[0].max()
range_ = max_ - min_
# shift df left by the min so the new min is 0
df[0] -= min_
# rescale data to [0,0.5] or [0,1]
if i == 0: # high
scale_factor = 2
intercept = 0.5
else: # low
scale_factor = 2
intercept = 0.5
df[0] /= range_ * scale_factor
# rescale data to [0.5, 1] or [0, 1]
df[0] += intercept
# create similarity histogram and save it
try:
plt.hist(df[0], bins=50, facecolor='green')
plt.savefig(pngfile, dpi=150)
plt.clf()
except ValueError as e:
printd('Unable to generate histogram of scaled data')
# write to csv
df.to_csv(outfile, sep='\t', index=False, header=False)
