在现代JavaScript中,这些代码段之间在概念上有所区别:
a = df.select_dtypes(np.number).mean()
b = df[df.columns.difference(a.index)].mode().iloc[0]
#alternative
#b = df.select_dtypes(object).mode().iloc[0]
print (df[df.columns.difference(a.index)].mode())
A F
0 d b
1 e NaN
df = df.fillna(a.append(b))
print (df)
A B C D F
0 e 4.5 7.0 1.0 b
1 d 4.5 5.0 3.0 b
2 d 4.0 9.0 5.0 a
3 d 5.0 4.0 2.0 b
4 e 5.0 2.0 1.0 b
5 d 4.0 3.0 0.0 b
和
button.addEventListener('click', () => this.clickHandler())
我应该优先选择另一个吗?