Week 2 - Python and Vectorization

Vectorization

    • Z = W^TX+b , W \in \mathcal R^{n_x} , X \in \mathcal R^{n_x}
    • if non-verctorized:
    • if vectorized:
    • it is much faster

Vectorizing Logistic Regression

    • b is real number, it will be automatically changed to vector to be added each element of matrix (python broadcasting)

A note on python/numpy vectors

  • to simplify code and to avoid bug, don't use rank 1 array