a j @s0ddlZddlZddlmZddZddZdS)N)suppresscCs$t|tj o"t|tjo"t|S)aTest if x is NaN. This function is meant to overcome the issue that np.isnan does not allow non-numerical types as input, and that np.nan is not float('nan'). Parameters ---------- x : any type Any scalar value. Returns ------- bool Returns true if x is NaN, and false otherwise. Examples -------- >>> import numpy as np >>> from sklearn.utils._missing import is_scalar_nan >>> is_scalar_nan(np.nan) True >>> is_scalar_nan(float("nan")) True >>> is_scalar_nan(None) False >>> is_scalar_nan("") False >>> is_scalar_nan([np.nan]) False ) isinstancenumbersIntegralRealmathisnan)xr s &