Release Notes

Version 0.7.2: January 23, 2024

  • Fixed several deprecation warnings and incompatibilities with newer versions of biopython and pandas.


  • As a result of updating biopython compatibility, the output of the align subcommand may differ slightly in terms of the alignment start position when the alignment starts with a mismatch and which alignment is selected from the set of equally scoring alignments.

Version 0.7.1: October 2, 2022

  • Added allowance of U characters in nucleotide distance calculations with equivalence to T.


  • Changed average quality score calculation to use the probability calculation instead of a simple mean on the scores.

Version 0.7.0: October 28, 2021

  • Updated dependencies to biopython >= v1.77.


  • Fixed a bug causing execution failures in the sequential and reference commands when passing multiple input file sets.


  • Added the --mem argument to control the memory allocation for cd-hit-est.

  • Updated the default usearch/vsearch clustering parameters for the barcode subcommand to only require 1 word match (see the minwordmatches argument to usearch/vsearch), as the default value of 12 was automatically excluding short sequence matches. The set subcommand retains the default minwordmatches value of 12.


  • Fixed a bug in the set command causing an NaN to integer conversion error with some data sets.

  • Added the the --pad argument to the barcode command to control how to deal with truncated barcode sequences. Barcode sequences have to be identical in length, so --pad provides a mechanism to either pad the ends of short barcodes with N characters or exclude barcodes shorter than the maximum length barcode from the distance calculations.


  • Will now modify the identifiers for primers specified via -p to avoid downstream issues parsing sequence headers. Whitespace and the default annotation delimiters (|=,) are now replaced with underscore characters (_).

Version 0.6.2: October 13, 2020

  • Updated to support Biopython v1.78.

Version 0.6.1: July 15, 2020

  • Fixed a bug in the blast wrappers caused by SeqIO.FastaIO.FastaWriter deprecation and increased the biopython dependency to v1.71.

Version 0.6.0: May 6, 2020

  • License changed to AGPL-3.


  • Added support for older Illumina headers without an index read when specifying --coord illumina.


  • Added support for older Illumina headers without and index read to the illumina subcommand.


  • Fixed a bug in the quality subcommand that caused the program to exit when encountering sequences that are entirely N characters.


  • Added support for older Illumina headers without an index read when specifying --coord illumina.

Version 0.5.13: August 29, 2019

  • Fixed .ix pandas deprecation warning.

Version 0.5.12: August 5, 2019

  • Increased pandas version requirement to v0.24+ with compatibility fixes for pandas v0.24.0.

Version 0.5.11: January 30, 2019

  • Slightly changed version number display in commandline help.


  • Removed the --log and --failed arguments from the all and barcode subcommands because they do nothing.

  • Added the --length argument to all subcommands which defines the ratio of minimum sequence lengths allowed in a cluster.

  • Added error handling for when --ident is less than recommended value.

  • Increased maximum memory allocation for cd-hit-est to 3GB.

Version 0.5.10: October 19, 2018

  • Documentation added for UMI error correction.

  • Added IO.printDebug to the API.


  • Added the subcommands set and barcode where set is the previous error estimation method (using UMI read groups). The new barcode method generates pairwise Hamming distance distributions for sequences containied in header annotations (typically UMI barcode sequences).

  • Added distance and threshold output files containing pairwise distance histograms and clustering thresholds for use with the corresponding subcommands in ClusterSets.

  • Increased default minimum sequence count in the set subcommand to 20.

Version 0.5.9: September 2, 2018

  • Add the -o argument to most tools, which allows explicit declaration of the output file name.

  • Added IO.printWarning and IO.printError API functions for handling standard error messaging.

  • Split IO.printProgress API function into IO.printProgress (percentage) and IO.printCount (raw counts).

  • Moved a significant number of functions and classes from the executable scripts into the API.


  • Removed support for the regex primer file format.


  • Changed default of the --rc argument to tail and added none option for previous default.

Version 0.5.8: July 13, 2018

  • Fixed installation incompatibility with pip 10.


  • Added support for CD-HIT.


  • Significant performance improvements.

Version 0.5.7: March 19, 2018


  • Fixed an error wherein the program would exit if all sequences in an UMI read group had a Phred quality score of 0 in a given position.


  • Added support for EMBL-EBI ENA header format to the sra subcommand.


  • Added extract subcommand which will remove/annotation subsequences in fixed position without requiring a primer sequence match.

  • Added --pf and --bf arguments to all subcommands allowing renaming of output PRIMER and BARCODE fields, respectively.

  • Removed SEQORIENT output field from score subcommand as the mode does not check the reverse complement.


  • Added the --act argument to provide a mechanism for collapsing values of duplicate fields copied across files.


  • Added merge subcommand to combined separate annotations into a single entry.

Version 0.5.6: January 17, 2018


  • Fixed a bug causing copy fields (--cf argument) to be processed incorrectly.


  • Improved reporting in log file.

Version 0.5.5: December 26, 2017


  • Fixed a bug that caused the align subcommand to error if input sequences where shorter than the minimum specified by the –minlen argument. It will now simply fail such sequences.


  • Moved functionality of previous ClusterSets command into the set subcommand.

  • Added the all subcommand to cluster all sequences without considering annotation groups.

  • Added the barcode subcommand which allows for clustering of reads based on a barcode sequence instead of the read data.

  • Renamed -id argument to --ident for consistency with AssemblePairs.


  • Fixed a bug wherein CollapseSeq would match partial sequences against longer sequences that were otherwise identical up until the missing end characters.

  • Added detailed log output.


  • Fixed a division by zero warning in the log output when there were no observed mismatches.


  • New tool to generate consensus annotations or filter reads based on annotation groupings.

Version 0.5.4: July 1, 2017

  • All tools will now print detailed help if no arguments are provided.


  • Fixed a typo in the console log of the muscle subcommand.


  • Added the migec subcommand to convert headers from the MIGEC tool.


  • Fixed a division by zero error when there were no observed mismatches.

  • Bounded error rate to a minimum of 10^-9 (Q=90).

Version 0.5.3: February 14, 2017

License changed to Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).


  • Changed the behavior of the --failed argument so that failed output are in the same orientation as the input sequences. Meaning, the --rc argument is ignored for failed output.

  • Added the sequential subcommand which will first attempt de novo assembly (align subcommand) following by reference guided assembly (reference subcommand) if de novo assembly fails.

  • Added blastn compatibility to reference subcommand.

  • Added the option --aligner to the reference subcommand to allow use of either blastn or usearch for performing the local alignment. Defaults to the usearch algorithm used in previous releases.

  • Added the option --dbexec to the reference subcommand to allow specification of the reference database build tool (eg, makeblastdb).

  • Changed masking behavior to none and word length to 9 in reference subcommand when using usearch as the aligner.

  • Internal modifications to the reference subcommand to rebuild the database before alignments for performance reasons.

  • Fixed a deprecation warning appearing with newer versions of numpy.


  • Fixed a bug in the read group error rate calculation wherein either a consensus sequence or read group that was completely N characters would cause the program to exit with a division by zero error. Now, such non-informative read groups will be assigned an error rate of 1.0.


  • Added vsearch compatibility.

  • Fixed a bug wherein sets containing empty sequences were being fed to usearch, rather than automatically failed, which would cause usearch v8 to hang indefinitely.

  • Fixed an incompatibility with usearch v9 due to changes in the way usearch outputs sequence labels.

  • Changed masking behavior of usearch to none.

  • Changed how gaps are handling before passing sequences to usearch. Gaps are now masked (with Ns) for clustering, instead of removed.


  • Fixed a fatal error with newer versions of pandas.


  • Added the select subcommand, which allows filtering of sequences based on annotation value matches or mismatches.

  • Altered the behavior of the -u argument for both the sample and samplepair subcommands. If -u is specified, sampling is performed as in previous versions wherein samples will be drawn from only fields with the specified annotation values up to n total reads. However, if -u is not specified with -f repeated sampling will now be performed for each unique annotation value in the specified field, generating output with up to n reads per unique annotation value.

Version 0.5.2: March 8, 2016

Fixed a bug with installation on Windows due to old file paths lingering in presto.egg-info/SOURCES.txt.

Improvements to commandline usage help messages.

Updated license from CC BY-NC-SA 3.0 to CC BY-NC-SA 4.0.


  • Added the flag --fill to the reference subcommand to allow insertion of the reference sequence into the non-overlapping region of assembled sequences. Use caution when using this flag, as this may lead to chimeric sequences.

  • Changed default --minlen to 8 in align subcommand.

Version 0.5.1: December 4, 2015


  • Fixed bug wherein --failed flag did not work.

Version 0.5.0: September 7, 2015

Conversion to a proper Python package which uses pip and setuptools for installation.

The package now requires Python 3.4. Python 2.7 is not longer supported.

The required dependency versions have been bumped to numpy 1.8, scipy 0.14, pandas 0.15, and biopython 1.65.


  • Divided IgCore functionality into the separate modules: Annotation, Commandline, Defaults, IO, Multiprocessing and Sequence.

Version 0.4.8: September 7, 2015

Added support for additional input FASTA (.fna, .fa), FASTQ (.fq) and tab-delimited (.tsv) file extensions.


  • Fixed a bug in the rename subcommand wherein renaming to an existing field deleted the old annotation, but did not merge the renamed annotation into the existing field.

  • Added the copy subcommand which will copy annotations into new field names or merge the annotations of existing fields.

  • Added the --act argument to the copy and rename subcommands allowing collapse following the copy or rename operation.

  • Added a commandline check to ensure that the -f, -k and --act arguments contain the same number of fields for both the rename and copy subcommands.

Version 0.4.7: June 5, 2015


  • Modified scoring functions to permit asymmetrical scores for N and gap characters.


  • Added support for SRA style coordinate information where the where the read number has been appended to the spot number.

  • Altered scoring so gap characters are counted as mismatches in the error rate and identity calculations.


  • Altered scoring so gap characters are counted as mismatches in the diversity and error rate calculations.


  • Added support for SRA style sequence headers where the read number has been appended to the spot number; eg, output from fastq-dump -I --split-files file.sra.


  • Added missing OUTPUT console log field.

  • Changed --bf and --cf arguments to -f and -k, respectively.


  • Altering scoring behavior for N characters such that Ns in the input sequence are always counted as a mismatch, while Ns in the primer sequence are counted as a match, with priority given to the input sequence score.

  • Added --gap argument to the align subcommand which allows users to specify the gap open and gap extension penalties for aligning primers. Note: gap penalties reduce the match count for purposes of calculating ERROR.


  • Added support for SRA style coordinate information where the where the read number has been appended to the spot number.

Version 0.4.6: May 13, 2015


  • Changed --maxmiss argument to --maxgap and altered the behavior to only perform deletion of positions based on gap characters (only “-” or “.” and not “N” characters).

  • Added an error rate (--maxerror) calculation based on mismatches from consensus. The --maxerror argument is mutually exclusive with the --maxdiv argument and provides similar functionality. However, the calculations are not equivalent, and --maxerror should be considerably faster than --maxdiv.

  • Added exclusion of positions from the error rate calculation that are deleted due to exceeding the --maxgap threshold .

  • Fixed misalignment of consensus sequence against input sequences when positions are deleted due to exceeding the --maxgap threshold.


  • New script to cluster read groups by barcode field (eg, UID barcodes) into clustering within the read group.


  • New script to handle conversion of different sequence description formats to the pRESTO format.


  • Added count of masked characters to log output of maskqual subcommand.

  • Changed repeats subcommand log field REPEAT to REPEATS.


  • Changed -f argument to --1f argument.

  • Added --2f argument to copy file 2 annotations to file 1.


  • Moved convert subcommand to the generic subcommand of the new ConvertHeaders script and modified the conversion behavior.

Version 0.4.5: March 20, 2015

Added details to the usage documentation for each tool which describes both the output files and annotation fields.

Renamed --clean argument to --failed argument with opposite behavior, such that the default behavior of all scripts is now clean output.


  • Features added for Change-O compatibility.

  • Features added for PairSeq performance improvements.

  • Added custom help formatter.

  • Modifications to internals of multiprocessing code.

  • Fixed a few typos in error messages.


  • Added reference subcommand which uses V-region germline alignments from ublast to assemble paired-ends.

  • Removed mate-pair matching operation to increase performance. Now requires both input files to contain matched and uniformly ordered reads. If files are not synchronized then PairSeq must be run first. AssemblePairs will check that coordinate info matches and error if the files are not synchronized. Unpaired reads are no longer output.

  • Added support for cases where one mate pair is the subsequence of the other.

  • Added --scanrev argument to allow for head sequence to overhang end of tail.

  • Removed truncated (quick) error calculation in align subcommand.

  • Changed default values of the --maxerror and --alpha arguments of the align subcommand to better tuned parameters.

  • Changed internal selection of top scoring alignment to use Z-score approximation rather than a combination of error rate and binomial mid-p value.

  • Internal changes to multiprocessing structure.

  • Changed inserted gap character from - to N in join subcommand for better compatibility with the behavior of IMGT/HighV-QUEST.

  • Changed PVAL log field to PVALUE.

  • Changed HEADSEQ and TAILSEQ log fields to SEQ1 and SEQ2.

  • Changed HEADFIELDS and TAILFIELDS log fields to FIELDS1 and FIELDS2.

  • Changed precision of ERROR and PVALUE log fields.

  • Added more verbose logging.


  • Fixed bug where low quality positions where not being masked in single sequence barcode groups.

  • Added copy field (--cf) and copy action (--act) arguments to generate consensus annotations for barcode read groups.

  • Changed maximum consensus quality score from 93 to 90.


  • Added --keep argument to allow retention of sequences with high missing character counts in unique sequence output file.

  • Removed case insensitivity for performance reasons. Now requires all sequences to have matching case.

  • Removed first and last from --act choices to avoid unexpected behavior.


  • Changed behavior of N characters in primer identification. Ns now count as a match against any character, rather than a mismatch.

  • Changed behavior of mask mode such that positions masked with Ns are now assigned quality scores of 0, rather than retaining their previous scores.

  • Fixed a bug with the align subcommand where deletions within the input sequence (gaps in the alignment) were causing an incorrect barcode start position.


  • Performance improvements. The tool should now be considerably faster on very large files.

  • Specifying the --failed argument to request output of sequences which do not have a mate pair will increase run time and memory usage.


  • Add ‘cat’ action to collapse subcommand which concatenates strings into a single annotation.


  • Removed --clean (and --failed) flag from all subcommands.

  • Added progress updates to sample and samplepair subcommands.

  • Performance improvements to samplepair subcommand.

Version 0.4.4: June 10, 2014


  • Removed a linux-specific dependency, allowing SplitSeq to work on Windows.

Version 0.4.3: April 7, 2014


  • Fixed bug that occurs with Python 2.7.5 on OS X.


  • Fixed bug in samplepairs subcommand that occurs with Python 2.7.5 on OS X.

Version 0.4.2: March 20, 2014

Increased verbosity of exception reporting.


  • Updates to consensus functions to support changes to BuildConsensus.


  • Set default alpha to 0.01.


  • Added support for --freq value parameter to quality consensus method and set default value to 0.6.

  • Fixed a bug in the frequency consensus method where missing values were contributing to the total character count at each position.

  • Added the parameter --maxmiss value which provides a cut-off for removal of positions with too many N or gap characters .


  • Renamed the --reverse parameter to --revpr.


  • Removed convert subcommand.

Version 0.4.1: January 27, 2014

Changes to the internals of multiple tools to provide support for multiprocessing in Windows environments.

Changes to the internals of multiple tools to provide clean exit of child processes upon kill signal or exception in sibling process.

Fixed unexpected behavior of --outname and --log arguments with multiple input files.


  • Added reporting of unknown exceptions when reading sequence files

  • Fixed scoring of lowercase sequences.


  • Fixed a typo in the log output.


  • Fixed a typo in the log output.


  • Fixed bug where tool would improperly exit if no sets passed threshold criteria.

  • Fixed typo in console output.


  • Added trim mode which will cut the region before primer alignment, but leave primer region unmodified.

  • Fixed a bug with lowercase sequence data.

  • Fixed bug in the console and log output.

  • Added support for primer matching when setting --maxerr 1.0.


  • Added count of sequences without any valid fields (FAIL) to console output.


  • Added count of records without any valid fields (FAIL) to console output.


  • Fixed typo in console output of samplepair subcommand.

  • Added increase of the open file limit to the group subcommand to allow for a large number of groups.

Version 0.4.0: September 30, 2013

Minor name changes were made to multiple scripts, functions, parameters, and output files.

AlignSets, AssemblePairs, BuildConsensus, EstimateError, FilterSeq, and MaskPrimers are now multithreaded. The number of simultaneous processes may be specified using --nproc value. Note this means file ordering is no longer preserved between the input and output sequence files.

Performance improvements were made to several tools.

The universal --verbose parameter was replaced with --log file_name which specifies a log file for verbose output, and disables verbose logging if not specified.

The report of input parameters and sequence counts is now separate from the log and is always printed to standard output.

Added a progress bar to the standard output of most tools.

Added a universal --outname file_prefix parameter which changes the leading portion of the output file name. If not specified, the current file name is used (excluding the file extension, as per the previous behavior).

Added a universal --clean parameter which if specified forces the tool not to create an output file of sequences which failed processing.


  • Changes to parameters and internals of multiple functions.

  • Added functions to support multithreading for single-end reads, paired-end reads, and barcode sets.

  • Added safe annotation field renaming.

  • Added progress bar, logging and output file name conversion support.

  • Moved reusable AssemblePairs, BuildConsensus, PairSeq, and SplitSeq. operations into IgCore.


  • Coordinate information is now specified by a coordinate type, rather than a delimiter, using the --coord header_type parameter, where the header type may be one of illumina, solexa, sra, 454, presto.


  • Sequences with a missing character count exceeding the user limit defined by -n maximum_missing_count are now exported to a separate collapse-undetermined output file, rather than included in the collapse-unique sequence output.


  • Now outputs error estimations for positions, quality scores, nucleotide pairs, and annotation sets.

  • Machine reported quality scores and empirical quality scores have been added to all output tables.


  • Added length subcommand to filter sequences by minimum length.


  • Coordinate information has been redefined as per AssemblePairs.


  • Added new subcommand convert which attempts to reformat sequence headers into the pRESTO format.

  • The rename subcommand will now append entries if the new field name already exists in the sequence header, rather than replace the entry.

Version 0.3 (prerelease 6): August 13, 2013

Toolkit is now dependent upon pandas 0.12 for the estimateError tool.


  • Changed MUSCLE execution to faster settings (-diags, -maxiters 2).


  • Added repeat subcommand to filter sequences with -n (value) repetitions of a single character and.

  • Changed -n parameter of ambig subcommand from fractional value to a raw count.


  • New tool which estimates error of sequence sets by comparison to a consensus.


  • Bug fixes to alignment position calculation of align subcommand when primer alignment begins before start of sequence.

  • Removed --ann parameter.

Version 0.3 (prerelease 5): August 7, 2013

License changed to Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

IgPipeline Core:

  • Bug fixes to diversity calculation.

  • Added support for files where all sequences do not share the same annotation fields.

  • Added support for alternate scoring of gap and N-valued nucleotides.


  • Added --mode parameter with options of pad and cut to specify whether to extend or trim read groups to the same start position.

  • Fixed intermittent ‘muscle’ subcommand stdout pipe deadlock when executing MUSCLE.


  • Added join subcommand to support library preps where paired-end reads do not overlap.

  • Speed improvements to p-value calculations.


  • --div parameter converted to --maxdiv value to allow filtering of read groups by diversity.

  • Bug fixes to nucleotide frequency consensus method.

  • -q parameter renamed to --qual.


  • Added support for files where all sequences do not share the same annotation fields.


  • samplepair subcommand added to allow random sampling from paired-end file sets.

  • The behavior of the -c parameter of the sample and samplepair subcommands changed to allow multiple samplings with the same command.

Version 0.3 (prerelease 4): May 18, 2013

Initial public prerelease