This module provides one class for creation of ndsparse objects which behave similar to numpy ndarray objects, including slicing and basic arithmatic operations.
Sparse array objects are stored using a flat index and a data value, so only take up space for elements explicitly added which makes them efficient for storing large arrays where only a few positions are occupied.
Slicing returns an ndsparse object which can be converted to a dense numpy.ndarray by calling it's dense() method.
Single element access returns the stored value if available or a default value otherwise.