python - pandas.Series 产生 nan 值

Question

我在 pandas 中有一个数据集（名为 naa）

   id  cod                data  nivel_mont  nivel_jus

0 naa 1 2002-10-28 00:00:00 162.10 NaN 1 naa 1 2002-10-29 00:00:00 162.10 NaN 2 naa 1 2002-10-30 00:00:00 162.34 NaN 3 naa 1 2002- 11-01 13:00:00 162.10 NaN 4 naa 1 2002-11-02 15:00:00 162.20 NaN ... ... ... ... ... ... 6166 naa 1 2021-02- 13 00:00:00 165.20 NaN 6167 naa 1 2021-02-14 00:00:00 164.20 NaN 6168 naa 1 2021-02-15 00:00:00 162.40 NaN

正在做

a = naa.iloc[:, 2] b = naa.iloc[:, 3]

valores_naa = pd.Series（数据=b，索引=a）打印（valores_naa）

结果是

数据 2002-10-28 00:00:00 NaN 2002-10-29 00:00:00 NaN 2002-10-30 00:00:00 NaN 2002-11-01 13:00:00 NaN 2002-11-02 15:00:00 NaN .. 2021-02-13 00:00:00 NaN 2021-02-14 00:00:00 NaN 2021-02-15 00:00:00 NaN 2021-02-16 00:00: 00 NaN 2021-02-17 00:00:00 NaN 名称：nivel_mont，长度：6171，dtype：float64

为什么NaN价值观？我期待列'nivel_mon'的值

谢谢

标签： pythonpandas