55 - 内容 - df.fillna() - NaN转换

NaN转0 df.fillna(0)

import numpy as np
import pandas as pd
# 全部列
df = df.fillna(0)
df.fillna(0, inplace=True)
# 2句区别是新增与不新增
# 指定列
trans={"A":9,"B":8,"C":7,"D":6}
df.fillna(value=trans)

data_df = pd.DataFrame(data=[{"A":"bike", "B":"bike"},{"A":"car", "B":np.nan},{"A":"bus", "B":np.nan}])

df = df.fillna(0)

B列NAN空值由A列填补

data_df["B"].fillna(data_df["A"], inplace=True)

data_df = pd.DataFrame(data=[{"A":"bike", "B":"bike"},{"A":"car", "B":np.nan},{"A":"bus", "B":np.nan}])

data_df["B"].fillna(data_df["A"], inplace=True)