c6e04265f1
This commit introduces sparse index support for KDI files to enable fast random access during k-mer matching. It adds a new .kdx index file format and updates the KDI reader and writer to handle index creation and seeking. The changes include: - New KdxIndex struct and related functions for loading, searching, and writing .kdx files - Modified KdiReader to support seeking with the new index - Updated KdiWriter to create .kdx index files during writing - Enhanced KmerSetGroup.Contains to use the new index for faster lookups - Added a new 'match' command to annotate sequences with k-mer match positions The index is created automatically during KDI file creation and allows for O(log N / stride) binary search followed by at most stride linear scan steps, significantly improving performance for large datasets.
obitools V4
OBITools V4 is the new version of OBITools. They are closer to OBITools2 than to OBITools3. They are implemented in GO and are tens of times faster than OBITools2.
The git for OBITools4 is available at :
Installing OBITools V4
An installation script that compiles the new OBITools on your Unix-like system is available online. The easiest way to run it is to copy and paste the following command into your terminal
curl -L https://raw.githubusercontent.com/metabarcoding/obitools4/master/install_obitools.sh | bash
By default, the script installs the latest version of OBITools commands and other associated files into the /usr/local directory.
Installation Options
The installation script offers several options:
-l, --list List all available versions and exit.
-v, --version Install a specific version (e.g.,
-v 4.4.3). By default, the latest version is installed.-i, --install-dir Directory where obitools are installed (as example use
/usr/localnot/usr/local/bin).-p, --obitools-prefix Prefix added to the obitools command names if you want to have several versions of obitools at the same time on your system (as example
-p gwill producegobigrepcommand instead ofobigrep).
Examples
List all available versions:
curl -L https://raw.githubusercontent.com/metabarcoding/obitools4/master/install_obitools.sh | bash -s -- --list
Install a specific version:
curl -L https://raw.githubusercontent.com/metabarcoding/obitools4/master/install_obitools.sh | bash -s -- --version 4.4.3
Install in a custom directory with command prefix:
curl -L https://raw.githubusercontent.com/metabarcoding/obitools4/master/install_obitools.sh | \
bash -s -- --install-dir test_install --obitools-prefix k
In this last example, the binaries will be installed in the test_install directory and all command names will be prefixed with the letter k. Thus, obigrep will be named kobigrep.
Note on Version Compatibility
The names of the commands in the new OBITools4 are mostly identical to those in OBITools2.
Therefore, installing the new OBITools may hide or delete the old ones. If you want both versions to be
available on your system, use the --install-dir and --obitools-prefix options as shown above.
Continuing the analysis...
Before with OBITools2 to continue the analysis, obitab was used as last command to produce a tab delimited file that was loadable in R or in any spreadsheet. The generated file was huge and required to load the full dataset in memory to be produced. Hereby OBITools4 proposes to substitute the obitab usage by the ROBIFastRead R module.