Python code example for shape calculation matrix

This article mainly introduces the method of shape computing matrix in Python, which involves the implementation of Python mathematical operations, and the need for a friend can refer to the following

This example describes the method of shape calculation matrix in Python. Share to everyone for your reference, as follows:

When you see the machine learning algorithm, you notice the shape calculation matrix. Now, let's talk about my understanding.

>>> from numpy import *>>> import operator>>> a =mat ([[1,2,3],[5,6,9]]) >>> Amatrix ( [[1, 2, 3],    [5, 6, 9]])

>>> shape (a) (2, 3) >>> a.shape[0] #计算行数2 >>> a.shape[1] #计算列数3

Next is the explanation in Python.

Examples-------->>> Np.shape (Np.eye (3)) (3, 3) >>> np.shape ([[1, 2]]) (1, 2) >>> np.shape ([0] ) (1,) >>> np.shape (0) () >>> a = Np.array ([(1, 2), (3, 4)], dtype=[(' x ', ' I4 '), (' Y ', ' I4 ')]) >>> n P.shape (a) (2,) >>> A.shape (2,)