1 ,隨機創建 nd : np.random.random((3,5))
- 目的 : 創建矩陣,他的每個元素,都是 (0-1) 之間的任意數字
- 代碼 :
if __name__ == '__main__':
nd01 = np.random.random((3,5))
print(nd01)
==============================
[[0.32329977 0.02613646 0.45362838 0.22721246 0.02853882]
[0.63043526 0.55201018 0.87353207 0.7489845 0.13471557]
[0.32465195 0.21991956 0.55730863 0.26402729 0.00424244]]
2 ,保留兩位小數 : np.round(nd01,2)
- 代碼 :
if __name__ == '__main__':
nd01 = np.random.random((3,5))
nd02 = np.round(nd01,2)
print(nd01)
print(nd02)
==========================================
[[0.44196108 0.73306397 0.26397105 0.42657281 0.91022663]
[0.63444238 0.16830148 0.87519688 0.76766924 0.75185521]
[0.89804682 0.03131887 0.33325768 0.86841883 0.87295732]]
==========================================
[[0.44 0.73 0.26 0.43 0.91]
[0.63 0.17 0.88 0.77 0.75]
[0.9 0.03 0.33 0.87 0.87]]
3 ,區間內取數 : np.linspace(0,2,9)
- 在 0 - 2 之間取 9 個數字
- 代碼 :
if __name__ == '__main__':
nd01 = np.linspace(0,2,9)
print(nd01)
==========================
[0. 0.25 0.5 0.75 1. 1.25 1.5 1.75 2. ]
4 ,三角函數 :sin
if __name__ == '__main__':
nd01 = np.linspace(0,2 * np.pi,9)
nd02 = np.sin(nd01)
print(nd01)
print(nd02)
==============================
[0. 0.78539816 1.57079633 2.35619449 3.14159265 3.92699082
4.71238898 5.49778714 6.28318531]
[ 0.00000000e+00 7.07106781e-01 1.00000000e+00 7.07106781e-01
1.22464680e-16 -7.07106781e-01 -1.00000000e+00 -7.07106781e-01
-2.44929360e-16]