numpy_将nan替换为均值

# coding = utf-8
import numpy as np
def nan_fill(a):
    for i in range(a.shape[1]):
        temp_col = a[:, i]
        count_col_nan = np.count_nonzero(temp_col == temp_col)
        if count_col_nan != 0:
            not_nan_num = temp_col[temp_col == temp_col]
            temp_col[np.isnan(temp_col)] = not_nan_num.mean()
    return a

if __name__ == '__main__':
    a = np.arange(12).reshape(3, 4).astype(float)
    print(a)
    a[1, 2:] = np.nan
    print(a)
    a = nan_fill(a)
    print(a)


效果图，依次为原数组，含有nan的数组，替换均值后的数组：