在Pandas系列中找到第一个非零值

时间:2015-08-19 00:11:44

标签: python pandas series

我有一个数字Pandas系列,其中601行按日期索引,如下所示。这些值为零直到引入一些非零值的点。这一点因每个系列而异,所以我想找到一种方法来找到第一个非零值的索引,并从该点开始绘制。

Name: users, dtype: float64 dates
2015-08-17 14:29:59-04:00    18
2015-08-16 14:29:59-04:00     3
2015-08-15 14:29:59-04:00    11
2015-08-14 14:29:59-04:00    12
2015-08-13 14:29:59-04:00     8
2015-08-12 14:29:59-04:00    10
2015-08-11 14:29:59-04:00     6
2015-08-10 14:29:59-04:00     6
2015-08-09 14:29:59-04:00     7
2015-08-08 14:29:59-04:00     7
2015-08-07 14:29:59-04:00    13
2015-08-06 14:29:59-04:00    16
2015-08-05 14:29:59-04:00    12
2015-08-04 14:29:59-04:00    14
2015-08-03 14:29:59-04:00     5
2015-08-02 14:29:59-04:00     5
2015-08-01 14:29:59-04:00     8
2015-07-31 14:29:59-04:00     6
2015-07-30 14:29:59-04:00     7
2015-07-29 14:29:59-04:00     9
2015-07-28 14:29:59-04:00     7
2015-07-27 14:29:59-04:00     5
2015-07-26 14:29:59-04:00     4
2015-07-25 14:29:59-04:00     8
2015-07-24 14:29:59-04:00     8
2015-07-23 14:29:59-04:00     8
2015-07-22 14:29:59-04:00     9
2015-07-21 14:29:59-04:00     5
2015-07-20 14:29:59-04:00     7
2015-07-19 14:29:59-04:00     6
                             ..
2014-01-23 13:29:59-05:00     0
2014-01-22 13:29:59-05:00     0
2014-01-21 13:29:59-05:00     0
2014-01-20 13:29:59-05:00     0
2014-01-19 13:29:59-05:00     0
2014-01-18 13:29:59-05:00     0
2014-01-17 13:29:59-05:00     0
2014-01-16 13:29:59-05:00     0
2014-01-15 13:29:59-05:00     0
2014-01-14 13:29:59-05:00     0
2014-01-13 13:29:59-05:00     0
2014-01-12 13:29:59-05:00     0
2014-01-11 13:29:59-05:00     0
2014-01-10 13:29:59-05:00     0
2014-01-09 13:29:59-05:00     0
2014-01-08 13:29:59-05:00     0
2014-01-07 13:29:59-05:00     0
2014-01-06 13:29:59-05:00     0
2014-01-05 13:29:59-05:00     0
2014-01-04 13:29:59-05:00     0
2014-01-03 13:29:59-05:00     0
2014-01-02 13:29:59-05:00     0
2014-01-01 13:29:59-05:00     0
2013-12-31 13:29:59-05:00     0
2013-12-30 13:29:59-05:00     0
2013-12-29 13:29:59-05:00     0
2013-12-28 13:29:59-05:00     0
2013-12-27 13:29:59-05:00     0
2013-12-26 13:29:59-05:00     0
2013-12-25 13:29:59-05:00     0

1 个答案:

答案 0 :(得分:5)

假设您的系列名为s

s = s.sort_index()
start = s.loc[s != 0].index
if len(start) > 0:
    filtered_series = s.ix[start[0]:]

您的数据似乎在时间上向后排序(即最近的第一个),所以我首先对索引进行了排序。

然后我使用loc来获取系列中非负值的索引值。如果此列表返回任何内容(它可能是一个空列表),那么我使用.ix从上面计算的第一个非零索引值到系列结尾索引该系列。