pybedtools documentation — pybedtools 0.12.0 documentation (original) (raw)
Overview¶
The BEDTools suite of programs is widely used for genomic interval manipulation or “genome algebra”. pybedtools
wraps and extends BEDTools and offers feature-level manipulations from within Python.
See full online documentation, including installation instructions, athttps://daler.github.io/pybedtools/.
The GitHub repo is at https://github.com/daler/pybedtools.
Why pybedtools
?¶
Here is an example to get the names of genes that are <5 kb away from intergenic SNPs:
from pybedtools import BedTool
snps = BedTool('snps.bed.gz') # [1] genes = BedTool('hg19.gff') # [1]
intergenic_snps = snps.subtract(genes) # [2] nearby = genes.closest(intergenic_snps, d=True, stream=True) # [2, 3]
for gene in nearby: # [4] if int(gene[-1]) < 5000: # [4] print gene.name # [4]
Useful features shown here include:
[1]
support for all BEDTools-supported formats (here gzipped BED and GFF)[2]
wrapping of all BEDTools programs and arguments (here,subtract
andclosest
and passing the-d
flag toclosest
);[3]
streaming results (like Unix pipes, here specified bystream=True
)[4]
iterating over results while accessing feature data by index or by attribute access (here[-1]
and.name
).
In contrast, here is the same analysis using shell scripting. Note that this requires knowledge in Perl, bash, and awk. The run time is identical to thepybedtools
version above:
snps=snps.bed.gz genes=hg19.gff intergenic_snps=/tmp/intergenic_snps
snp_fields=zcat $snps | awk '(NR == 2){print NF; exit;}'
gene_fields=9
distance_field=$(($gene_fields + $snp_fields + 1))
intersectBed -a snps−bsnps -b snps−bgenes -v > $intergenic_snps
closestBed -a genes−bgenes -b genes−bintergenic_snps -d
| awk '($'$distance_field' < 5000){print $9;}'
| perl -ne 'm/[ID|Name|gene_id]=(.*?);/; print "$1\n"'
rm $intergenic_snps
See the Shell script comparison in the docs for more details on this comparison, or keep reading the full documentation athttp://daler.github.io/pybedtools.
As of 2022, pybedtools
is released under the MIT license; see LICENSE.txt for more info.
Note
If you use pybedtools
in your work, please cite the pybedtools manuscriptand the BEDTools manuscript:
Dale RK, Pedersen BS, and Quinlan AR. 2011. Pybedtools: a flexible Python library for manipulating genomic datasets and annotations. Bioinformatics 27(24):3423-3424.
Quinlan AR and Hall IM, 2010. BEDTools: a flexible suite of utilities for comparing genomic features. Bioinformatics 26(6):841–842.
Getting started¶
The documentation is separated into 4 main parts, depending on the depth you’d like to cover:
- Lazy, or just want to jump in? Check out Three brief examples to get a feel for the package.
- Want a guided tour? Give the Tutorial Contents a shot.
- More advanced features are described in the Topical Documentation section.
- Finally, doctested module documentation can be found in pybedtools Reference.
Contents:¶
- Installation
- Running tests, compiling docs
- Three brief examples
- Tutorial Contents
- Topical Documentation
- Design principles
- Creating a BedTool
- Saving BedTool results
- Using BedTool objects as iterators/generators
- Low-level operations
- Working with BAM files
- Notes on BAM file semantics
- Specifying genomes
- Randomization
- Wrapping new tools
- Comparisons
- Shell script comparison
- pybedtools development model
- Under the hood
- FAQs
- “Does pybedtools have a simple reader/writer for BED files?”
- “Can I create a BedTool object from an existing list?”
- “I’m getting an empty BedTool”
- “I’m getting a MalformedBedLineError”
- “I get a segfault when iterating over a BedTool object”
- “Can I add extra information to FASTA headers when using BedTool.sequence()?”
- “Too many files open” error
- Scripts
- pybedtools Reference
- Changelog
- Changes in v0.12.0
- Changes in v0.11.0
- Changes in v0.10.1
- Changes in v0.9.1
- Changes in v0.9
- Changes in v0.8.2
- Changes in v0.8.1
- Changes in v0.8.0
- Changes in v0.7.10
- Changes in v0.7.9
- Changes in v0.7.8
- Changes in v0.7.7
- Changes in v0.7.6
- Changes in v0.7.5
- Changes in v0.7.4
- Changes in v0.7.1
- Changes in v0.7.0
- Changes in v0.6.9
- Changes in v0.6.8
- Changes in v0.6.7
- Changes in v0.6.6
- Changes in v0.6.5
- Changes in v0.6.4
- Changes in v0.6.3
- Changes in v0.6.2
- Changes in v0.6.1
- Changes in v0.6
- Changes in v0.5.5
- Changes in v0.5