def write_merged_to_stdout():
# We assume for now all records match. Generally, need to verify.
log('About to merge ', in_fname1, in_fname2)
with gene_lib.open_compressed(in_fname1, 'rt') as in_f1_handle:
records1 = SeqIO.parse(in_f1_handle, format="fastq")
with gene_lib.open_compressed(in_fname2, 'rt') as in_f2_handle:
records2 = SeqIO.parse(in_f2_handle, format="fastq")
merged = merged_paired_ends(records1, records2)
Bio.SeqIO.write(merged, handle=sys.stdout, format='fastq')
def fastq_zst_records(filename):
# https://github.com/indygreg/python-zstandard - pip3 install zstandard
import zstandard as zstd
log(f"Reading {filename}...")
with open(filename, 'rb') as fastq_zst_handle:
fastq_handle = zstd.ZstdDecompressor().stream_reader(fastq_zst_handle)
# wrapper adds support for .readline(), for line in ...
fastq_text = io.TextIOWrapper(fastq_handle, encoding='ascii')
for record in SeqIO.parse(fastq_text, "fastq"):
yield record
def write_fastq_to_stdout():
log('About to transform ', in_fname)
with gene_lib.open_compressed(in_fname, 'rt') as in_f1_handle:
records = SeqIO.parse(in_f1_handle, format="fasta")
for (rec) in records:
string = str(rec.seq)
res_seq = SeqRecord(Seq(string),
id=rec.id,
name=rec.name,
description=rec.description,
letter_annotations={
"phred_quality":
[30 for i in range(len(string))]
})
Bio.SeqIO.write(res_seq, handle=sys.stdout, format='fastq')
def split_recompress(in_fname, out_basename, skip=[]):
"""
skip - indexes of parts to skip (still need to decompress but not compress)
"""
with gzip.open(in_fname, 'rb') as in_fastq:
for i, chunk_iter in enumerate(chunks(in_fastq, chunk_size=100_000_000)):
out_fname = f'{out_basename}.part{i}e8.fastq.gz'
t0 = time.time()
if i in skip:
log('Skipping', out_fname)
max(chunk_iter) # consume iterator, discarding values
else:
log('Writing', out_fname)
with gzip.open(out_fname + '.tmp', 'wb', compresslevel=2) as out_fastq_gz:
#with open(out_fname, 'wb') as out_fastq_gz:
out_fastq_gz.writelines(chunk_iter)
os.rename(out_fname + '.tmp', out_fname)
t1 = time.time()
log(t1 - t0, 'sec.')
def merged_paired_ends(records1, records2):
tot_good = 0
tot_great = 0
tot = 0
# log('in merged_paired_ends',records1,records2)
for (rec1, rec2) in zip(records1, records2):
tot += 1
str1 = str(rec1.seq)
str2 = str(rec2.seq.reverse_complement())
# log('-------------------------------------------\n matching ',str1,'\n',str2,'\n===================================================')
end1 = str1[-common_req:]
re = tre.compile(end1, tre.EXTENDED)
# we expect small errors here
res_seq = None
match = re.search(str2, tre.Fuzzyness(maxerr=init_err))
if match:
tot_good += 1
match_loc = match.groups()[0][0]
to_search_len = match_loc + common_req
fuzzyness = max(tot_err, ceil(0.1 * to_search_len))
re = tre.compile(str1[-to_search_len:], tre.EXTENDED)
match_tot = re.search(str2, tre.Fuzzyness(maxerr=fuzzyness))
# log('step1: matched ',end1,' at',match_loc,' testing prefix ',str2[:to_search_len],'cost ',match.cost)
if match_tot:
# if (tot_good % 100 == 0):
# log('fuzzyness = ', fuzzyness)
# log('step2: matched ',str1[-to_search_len:],' at',match_tot.groups()[0][0],' testing prefix ','cost ',match.cost)
tot_great += 1
# An arbitrary decision: take the common string from r2
res_str = str1[:-to_search_len] + str2
# TODO: preserve qualities
res_seq = SeqRecord(Seq(res_str),
id=rec1.id,
name=rec1.name,
description=rec1.description,
letter_annotations={
"phred_quality":
[30 for i in range(len(res_str))]
})
if (tot_great % step == 0):
log('nicely matched ', str1, '\n', str2, to_search_len,
match_tot.group(0), match.group(0), match_tot.cost,
match.cost)
# log('result = ',str(res_seq.seq))
yield res_seq
continue
res_str = str1 + ('N' * padding) + str2
res_seq = SeqRecord(Seq(res_str),
id=rec1.id,
name=rec1.name,
description=rec1.description,
letter_annotations={
"phred_quality":
[30 for i in range(len(res_str))]
})
if (tot % step == 0):
log(tot, tot_good, tot_great)
# log('matched ',str1,'\n',str2, len(str1), len(str2))
# log('result = ',str(res_seq.seq))
yield res_seq
re = tre.compile(sine[:sine_header], tre.EXTENDED)
fuzziness = tre.Fuzzyness(maxerr=maxerr)
for rec in records:
if reverse_complement:
cur_seq = rec.seq.reverse_complement()
else:
cur_seq = rec.seq
match = re.search(str(cur_seq), fuzziness)
if match:
# log(rec.seq)
#sine_location = match.groups() #returns tuple of tuples (in this case: ((2,78), ) for example
SeqIO.write(rec, sys.stdout, 'fastq')
# Writes to stdout, uncompresed
[sine_fname, header_len, max_error, reverse_complement,
merged_input_fname] = sys.argv[1:]
if reverse_complement not in {"forward", "rc"}:
raise ValueError('reverse_complement arg must be "forward" or "rc"')
log(f"About to screen {merged_input_fname} ({reverse_complement}) for {sine_fname} first {header_len} up to {max_error} err"
)
sine = gene_lib.get_sine_forward(sine_fname) #"B1.fasta"
filter_potential_sines(in_fname=merged_input_fname,
sine_string=sine,
sine_header=int(header_len),
maxerr=int(max_error),
reverse_complement=(reverse_complement == "rc"))
#from Bio.SeqRecord import SeqRecord
import gene_lib
from gene_lib import log
from gene_lib import get_sine_forward
def filter_potential_sines(in_fname, sine_string, sine_header=67, maxerr=19):
"""
Finds candidate SINEs with a certain distance from a prefix length.
To be used for preliminary screening (input for later steps).
"""
with gene_lib.open_any(in_fname, 'rt') as in_file_handle:
records = SeqIO.parse(in_file_handle, format="fastq")
re = tre.compile(sine[:sine_header], tre.EXTENDED)
fuzziness = tre.Fuzzyness(maxerr=maxerr)
for rec in records:
match = re.search(str(rec.seq), fuzziness)
if match:
# log(rec.seq)
#sine_location = match.groups() #returns tuple of tuples (in this case: ((2,78), ) for example
SeqIO.write(rec, sys.stdout, 'fastq')
# Writes to stdout, uncompresed
[sine_fname, merged_input_fname] = sys.argv[1:]
log('About to screen', merged_input_fname, 'for', sine_fname)
sine = gene_lib.get_sine_forward(sine_fname) #"B1.fasta"
filter_potential_sines(merged_input_fname, sine)
itertools.islice(shared_input_iterator, chunk_size - 1))
def split_recompress(in_fname, out_basename, skip=[]):
"""
skip - indexes of parts to skip (still need to decompress but not compress)
"""
with gzip.open(in_fname, 'rb') as in_fastq:
for i, chunk_iter in enumerate(chunks(in_fastq, chunk_size=100_000_000)):
out_fname = f'{out_basename}.part{i}e8.fastq.gz'
t0 = time.time()
if i in skip:
log('Skipping', out_fname)
max(chunk_iter) # consume iterator, discarding values
else:
log('Writing', out_fname)
with gzip.open(out_fname + '.tmp', 'wb', compresslevel=2) as out_fastq_gz:
#with open(out_fname, 'wb') as out_fastq_gz:
out_fastq_gz.writelines(chunk_iter)
os.rename(out_fname + '.tmp', out_fname)
t1 = time.time()
log(t1 - t0, 'sec.')
#split_recompress('Old-lung/old_lung_R1_001.fastq.gz', 'Old-lung/old_lung_R1_001')
if __name__ == '__main__':
[in_fname, out_basename, *skip] = sys.argv[1:]
skip = [int(i) for i in skip]
split_recompress(in_fname, out_basename, skip)
log('REMOVING', in_fname)
os.remove(in_fname) # may fail for /dev/stdin, /dev/fd/... etc. but that's OK
