NumPy (www.numpy.org) is Python's matrix library. Using numpy.array() and similar constructs, large matrices can be created and various mathematical operations (including matrix addition and multiplication) can be performed on them. NumPy also has many functions for manipulating the shapes of matrices. Another feature of NumPy is the presence of familiar mathematical functions such as sin(), cos(), and exp().

SciPy (www.scipy.org) is a toolbox that contains many advanced mathematical modules. Its machine-learning-related subpackages include cluster, stats, sparse, and optimize. SciPy is an important package that enables scientific computing in Python.