Randomly sample from a FASTQ file without loading the whole file into memory.

Trying out a few different methods:

fastq_rnd_seek.py - Indexes location of all @'s at beginning of lines and samples from array of those locations.

fastq_rnd_seek_proper.py - Seeks to random locations in the FASTQ file and searchs for the next @ at the beginning of a line.

fastq_rnd_seek_proper_re.py - Seeks to random locations in the FASTQ file and uses a regex to find the next "valid" FASTQ record.

fastq_rnd_seek.jl - A Julia implementation that seeks to random locations in the FASTQ file and searches for the next "valid" FASTQ record.

##Usage:

fastq_rnd_seek <input filename> <integer for sample level>