选择pandas的DataFrame中第一行的值

时间:2016-05-08 22:44:32

标签: python pandas dataframe

我有以下DataFrame

                  AAPL         F       IBM
    Date            
    2016-05-02  46.536664   13.62   143.881476
    2016-05-03  47.302004   13.43   142.752373
    2016-05-04  46.810001   13.31   142.871221
    2016-05-05  46.619999   13.32   145.070003
    2016-05-06  46.360000   13.44   147.289993

我想将每一列除以第一行的值并乘以100.计算后,前两行应如下所示:

                AAPL          F        IBM
    Date
    2016-05-02  100          100       100
    2016-05-03  101.63       98.60     99.21

我在挣扎,但我无法得到它。任何帮助表示赞赏

1 个答案:

答案 0 :(得分:4)

尝试这样的事情:

char[] array = new char[0];
assert array != null;
assert array.length == 0;
assert "".equals(new String(array));

df /= df.iloc[0]/100

测试:

df = df.apply(lambda x: x/x.iloc[0]*100)

输出:

In [51]: df
Out[51]:
                 AAPL      F         IBM
Date
2016-05-02  46.536664  13.62  143.881476
2016-05-03  47.302004  13.43  142.752373
2016-05-04  46.810001  13.31  142.871221
2016-05-05  46.619999  13.32  145.070003
2016-05-06  46.360000  13.44  147.289993