ELKI is described as ': "Environment for Developing KDD-Applications Supported by Index-Structures" is a development framework for data mining algorithms written in Java. It includes a large variety of popular data mining algorithms, distance functions and index structures' and is a Data Mining software in the business & commerce category. There are more than 10 alternatives to ELKI for a variety of platforms, including Linux, Mac, Windows, BSD and Web-based apps. The best ELKI alternative is R (programming language), which is both free and Open Source. Other great apps like ELKI are GNU Octave, SageMath, MATLAB and SciPy.