# An example of how shape calculates a matrix in Python

• 2020-05-30 20:28:17
• OfStack

The example in this paper describes the method of shape to calculate the matrix in Python. I will share it with you for your reference as follows:

When you look at machine learning algorithms, you notice that shape computes matrices and I'm going to tell you what I understand

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

``````
``````
>>> shape(a)
(2, 3)
>>> a.shape[0] # Calculate number of lines
2
>>> a.shape[1] # Calculate the number of columns
3

``````

Here 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')])
>>> np.shape(a)
(2,)
>>> a.shape
(2,)

``````

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