In [1]:
import numpy as np
In [11]:
vec = np.array([0, 1, np.nan, 3])
np.isnan(vec)
Out[11]:
In [12]:
~np.isnan(vec)
Out[12]:
nan $\neq$ nan
In [13]:
vec == np.nan
Out[13]:
In [14]:
vec != np.nan
Out[14]: