After using it for a while, I really like the Numpy multi-dimensional array. It's helpful to write algorithms with a concise yet readable and fairly general code. I wish to have the same thing in Java. Before coding a multi-dimensional array with a Numpy-like API myself, is there such a thing already ?
[PS] I searched a bit, did not see
So the closest match seems to be Colt ! http://acs.lbl.gov/software/colt/
It features a multi-dimensional array object, views over an array and your usual linear algebra ! And it's seems to be rather efficient.