January project
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The Eclipse January Project

What is this?

This is a library for handling Data in Java. It is inspired in part by NumPy and aims to provide similar functionality.

The Eclipse January project combines the core data structures projects of the following projects which originated the code.

Why use it?

  • Familiar. Provide familiar functionality, especially to NumPy users.
  • Robust. Has test suite and is used in production heavily at Diamond Light Source and Oak Ridge National Laboratory
  • No more passing double[]. IDataset provide a consistent object for basing APIs on with significantly improved clarity over using double arrays or similar.
  • Optimized. Optimized for speed and getting better all the time.
  • Scalable. Allows handling of data sets larger than available memory with "Lazy Datasets".
  • Focus on your algorithms. By reusing this library it allows you to focus on your code.

Getting Started

Clone the examples repository and have a look. Browse over to the examples for more information.


The current Javadocs are published here: https://eclipse.org/january/apidocs/


See the contribution guide for information on contributing to the Eclipse January Project.


The code is distributed under the Eclipse Public License.