2.8. Array New Axis¶
2.8.1. Recap¶
a = np.array([[1, 2, 3],
[4, 5, 6],
[7, 8, 9]])
a[:, 1]
# array([2, 5, 8])
a[:, 0:2]
# array([[1, 2],
# [4, 5],
# [7, 8]])
2.8.2. With Indexes¶
import numpy as np
a = np.array([[1, 2, 3],
[4, 5, 6],
[7, 8, 9]])
a[:, 1]
# array([2, 5, 8])
a[np.newaxis, :, 1]
# array([[2, 5, 8]])
a[:, np.newaxis, 1]
# array([[2],
# [5],
# [8]])
a[:, 1, np.newaxis]
# array([[2],
# [5],
# [8]])
2.8.3. With Slices¶
import numpy as np
a = np.array([[1, 2, 3],
[4, 5, 6],
[7, 8, 9]])
a[:, 0:2]
# array([[1, 2],
# [4, 5],
# [7, 8]])
a[np.newaxis, :, 0:2]
# array([[[1, 2],
# [4, 5],
# [7, 8]]])
a[:, np.newaxis, 0:2]
# array([[[1, 2]],
#
# [[4, 5]],
#
# [[7, 8]]])
a[:, 0:2, np.newaxis]
# array([[[1],
# [2]],
#
# [[4],
# [5]],
#
# [[7],
# [8]]])