Eclipse January

Java Data Structures for Science

What is January?

Eclipse January is a set of libraries for handling numerical data in Java. It is inspired in part by NumPy and aims to provide similar functionality.


Getting Started Guide.

Quickstart Interactive Lab A step-by-step tutorial with no download required.

Browse through the examples:
Basic Example show simple concepts for array creation, maths and slicing.
NumPy Examples show how common NumPy constructs map to Eclipse Datasets.
Slicing Examples demonstrate slicing, including how to slice a small amount of data out of a dataset too large to fit in memory all at once.
Error Examples demonstrate applying an error to datasets.
Iteration Examples demonstrate a few ways to iterate through your datasets.
Lazy Examples demonstrate how to use datasets which are not entirely loaded in memory.


Familiar. Provide familiar functionality, especially to NumPy users.
Robust. Has test suite and is used in production heavily at Diamond Light Source.
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.


Update Sites:
Eclipse January 2.3.2 (zip)

Want more?
More downloads


- Eclipse January project page

- Eclipse Science Working Group

- API documentation

- Multi-Dimensional Arrays in Java with Eclipse January

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