Skip to content


Repository files navigation

LArray: N-dimensional labelled arrays

Build Status Documentation Status

LArray is an open source Python library that aims to provide tools for easy exploration and manipulation of N-dimensional labelled data structures.

Library Highlights

  • N-dimensional labelled array objects to store and manipulate multi-dimensional data
  • I/O functions for reading and writing arrays in different formats: CSV, Microsoft Excel, HDF5, pickle
  • Arrays can be grouped into Session objects and loaded/dumped at once
  • User interface with an IPython console for rapid exploration of data
  • Compatible with the pandas library: Array objects can be converted into pandas DataFrame and vice versa.


Pre-built binaries

The easiest route to installing larray is through Conda. For all platforms installing larray can be done with:

conda install -c larray-project larray

This will install a lightweight version of larray depending only on Numpy and Pandas libraries only. Additional libraries are required to use the included graphical user interface, make plots or use special I/O functions for easy dump/load from Excel or HDF files. Optional dependencies are described below.

Installing larray with all optional dependencies can be done with

conda install -c larray-project larrayenv

You can also first add the channel larray-project to your channel list

conda config --add channels larray-project

and then install larray (or larrayenv) as

conda install larray

Building from source

The latest release of LArray is available from

Once you have satisfied the requirements detailed below, simply run:

python install

Required Dependencies

  • Python 3.8, 3.9, 3.10 or 3.11
  • numpy (1.22 or later)
  • pandas (0.20 or later)

Optional Dependencies

For IO (HDF, Excel)

  • pytables: for working with files in HDF5 format.
  • xlwings: recommended package to get benefit of all Excel features of LArray. Only available on Windows and Mac platforms.
  • openpyxl: recommended package for reading and writing Excel 2010 files (ie: .xlsx)
  • xlsxwriter: alternative package for writing data, formatting information and, in particular, charts in the Excel 2010 format (ie: .xlsx)
  • xlrd: for reading data and formatting information from older Excel files (ie: .xls)
  • xlwt:
    for writing data and formatting information to older Excel files (ie: .xls)
  • larray_eurostat: provides functions to easily download EUROSTAT files as larray objects. Currently limited to TSV files.

For Graphical User Interface

LArray includes a graphical user interface to view, edit and compare arrays.

  • pyqt (version 5): required by larray-editor (see below).
  • pyside: alternative to PyQt.
  • qtpy: required by larray-editor.
  • larray-editor: required to use the graphical user interface associated with larray. It assumes that qtpy and either pyqt or pyside are installed. On windows, creates also a menu LArray in the Windows Start Menu.

For plotting


  • pydantic: required to use CheckedSession.


The official documentation is hosted on ReadTheDocs at

Get in touch

  • To be informed of each new release, please subscribe to the announce mailing list.
  • For questions, ideas or general discussion, please use the Google Users Group.
  • To report bugs, suggest features or view the source code, please go to our GitHub website.