comparison YAC/yac.py @ 5:ad813be00215 draft default tip

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author drosofff
date Sat, 31 May 2014 15:12:15 -0400
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4:2f536ef15f49 5:ad813be00215
1 #!/usr/bin/python
2 # yac = yet another clipper
3 # v 1.0.0
4 # Usage yac.py $input $output $adapter_to_clip $min $max $Nmode
5 # Christophe Antoniewski <drosofff@gmail.com>
6
7 import sys, string
8
9 class Clip:
10 def __init__(self, inputfile, outputfile, adapter, minsize, maxsize):
11 self.inputfile = inputfile
12 self.outputfile = outputfile
13 self.adapter = adapter
14 self.minsize = int(minsize)
15 self.maxsize = int(maxsize)
16 def motives (sequence):
17 '''return a list of motives for perfect (6nt) or imperfect (7nt with one mismatch) search on import string module'''
18 sequencevariants = [sequence[0:6]] # initializes the list with the 6mer perfect match
19 dicsubst= {"A":"TGCN", "T":"AGCN", "G":"TACN", "C":"GATN"}
20 for pos in enumerate(sequence[:6]):
21 for subst in dicsubst[pos[1]]:
22 sequencevariants.append(sequence[:pos[0]]+ subst + sequence[pos[0]+1:7])
23 return sequencevariants
24 self.adaptmotifs= motives(self.adapter)
25
26 def scanadapt(self, adaptmotives=[], sequence=""):
27 '''scans sequence for adapter motives'''
28 if sequence.rfind(adaptmotives[0]) != -1:
29 return sequence[:sequence.rfind(adaptmotives[0])]
30 for motif in adaptmotives[1:]:
31 if sequence.rfind(motif) != -1:
32 return sequence[:sequence.rfind(motif)]
33 return sequence
34
35 def clip_with_N (self):
36 '''clips adapter sequences from inputfile.
37 Reads containing N are retained.'''
38 iterator = 0
39 id = 0
40 F = open (self.inputfile, "r")
41 O = open (self.outputfile, "w")
42 for line in F:
43 iterator += 1
44 if iterator % 4 == 2:
45 trim = self.scanadapt (self.adaptmotifs, line.rstrip() )
46 if self.minsize <= len(trim) <= self.maxsize:
47 id += 1
48 print >> O, ">%i\n%s" % (id, trim)
49 F.close()
50 O.close()
51 def clip_without_N (self):
52 '''clips adapter sequences from inputfile.
53 Reads containing N are rejected.'''
54 iterator = 0
55 id = 0
56 F = open (self.inputfile, "r")
57 O = open (self.outputfile, "w")
58 for line in F:
59 iterator += 1
60 if iterator % 4 == 2:
61 trim = self.scanadapt (self.adaptmotifs, line.rstrip() )
62 if "N" in trim: continue
63 if self.minsize <= len(trim) <= self.maxsize:
64 id += 1
65 print >> O, ">%i\n%s" % (id, trim)
66 F.close()
67 O.close()
68
69 def __main__ (inputfile, outputfile, adapter, minsize, maxsize, Nmode):
70 instanceClip = Clip (inputfile, outputfile, adapter, minsize, maxsize)
71 if Nmode == "accept":
72 instanceClip.clip_with_N()
73 else:
74 instanceClip.clip_without_N()
75
76 if __name__ == "__main__" :
77 input = sys.argv[1]
78 output = sys.argv[2]
79 adapter = sys.argv[3]
80 minsize = sys.argv[4]
81 maxsize = sys.argv[5]
82 Nmode = sys.argv[6]
83 __main__(input, output, adapter, minsize, maxsize, Nmode)