python - 如何在Python中获取数组中所有NaN元素的索引？

Question

我有一个数组

   [     nan,      nan,      nan,  1633.32,  1661.24,     0.  ],
   [     nan,      nan,      nan,  2885.94,  3264.09,     0.  ],
   [  605.48,      nan,   599.27,   664.47,   670.68,     0.  ],
   [     nan,      nan,      nan,   874.59,   783.86,     0.  ],
   [ 1596.01,      nan,  1469.77,  1731.26,  1514.86,     0.  ]]

有没有办法知道“nan”元素的索引(行，列)

Answer 1

使用numpy模块中的np.isnan和np.argwhere函数组合的解决方案:

import numpy as np

arr = np.array([[     np.NaN,      np.NaN,      np.NaN,  1633.32,  1661.24,     0.  ],
   [     np.NaN,      np.NaN,      np.NaN,  2885.94,  3264.09,     0.  ],
   [  605.48,      np.NaN,   599.27,   664.47,   670.68,     0.  ],
   [     np.NaN,      np.NaN,      np.NaN,   874.59,   783.86,     0.  ],
   [ 1596.01,      np.NaN,  1469.77,  1731.26,  1514.86,     0.  ]])

print(np.argwhere(np.isnan(arr)))

输出:

[[0 0]
 [0 1]
 [0 2]
 [1 0]
 [1 1]
 [1 2]
 [2 1]
 [3 0]
 [3 1]
 [3 2]
 [4 1]]