fastq长度计算

1. python

from collections import Counter
with open('srg1.r1.paired.fq','r') as Fileout, open('srg1.r1.paired.results.txt','w') as Filein:
  i = 4
  dic, arr = {}, []
  while True:
      line = Fileout.readline()
      i += 1
      if i%4 == 2:
          arr.append(len(str(line)))
      if not line:
          break

2. shell

awk 'NR%4 == 2 {lengths[length($0)]++} END {for (l in lengths) {print l, lengths[l]}}' file.fastq

And

awk 'NR%4 == 2 {lengths[length($0)]++ ; counter++} END {for (l in lengths) {print l, lengths[l]}; print "total reads: " counter}' file.fastq