seq-qc 0.16.0

utilities for performing various preprocessing steps on sequencing reads

# seq_qc - Python package with modules for preprocessing sequencing reads

## About

seq_qc is a python package for performing various quality control tasks on sequencing reads. Currently, seq_qc has three programs for this - a dereplicator for paired-end or single-end reads, a tool for trimming reads based on length and quality score thresholds, and a tool for interleaving paired-end reads.

## Requirements

Python 2.7+ or 3.4+

Python Libraries:

• screed

## Installation

pip install seq_qc

## Usage

filter_replicates takes as input a fastq or fasta file. If the reads are paired-end, the pairs can either be in separate files or a single interleaved file. The types of replicates that filter_replicates can search for are exact, 5’-prefix, and reverse-complement replicates.

### Examples

filter_replicates -1 input_forward.fastq -2 input_reverse.fastq –prefix –rev-comp

filter_replicates -1 input_forward.fastq.gz -2 input_reverse.fastq.gz -o output_forward.fastq.gz -v output_reverse.fastq.gz –prefix –rev-comp

filter_replicates -1 input_interleaved.fastq -o output_interleaved.fasta –interleaved –format fasta –log output.log

filter_replicates -1 input_singles.fastq -o output_singles.fastq

qtrim takes only fastq files as input. It can perform a variety of trimming steps - including trimming low quality bases from the start and end of a read, trimming the read after the position of the first ambiguous base, and trimming a read using a sliding-window approach. It also supports cutting the read to a desired length by removing bases from the start or end of the read.

### Examples

qtrim -1 input_forward.fastq.gz -2 input_reverse.fastq.gz -o output_forward.fastq.gz -v output_reverse.fastq.gz -s output_singles.fastq.gz –qual-type phred33 –sliding-window 10:20

qtrim -1 input_interleaved.fastq -o output_interleaved.fastq –interleaved –leading 20 –trailing 20 –trunc-n –min-len 60

interleave_pairs takes paired reads in separate fastq or fasta files and interleaves them in a single file. It can also act as a simple format conversion tool by allowing the input to be in fastq format and the output in fasta format.

### Examples

interleave_pairs -1 input_forward.fastq.gz -2 input_reverse.fastq.gz –format fasta -o output_interleaved.fasta

interleave_pairs - 1 input_forward.fasta -2 input_reverse.fasta –format fasta -o output_interleaved.fasta