zoukankan      html  css  js  c++  java
  • pandas.resample()

    http://www.cnblogs.com/hhh5460/p/5596340.html

    resample与groupby的区别:
    resample:在给定的时间单位内重取样
    groupby:对给定的数据条目进行统计

    函数原型:
    DataFrame.resample(rule, how=None, axis=0, fill_method=None, closed=None, label=None, convention='start', kind=None, loffset=None, limit=None, base=0)
    其中,参数how已经废弃了


    下面开始练习

    import numpy as np
    import pandas as pd

     
    Start by creating a series with 9 one minute timestamps.

    index = pd.date_range('1/1/2000', periods=9, freq='T')
    series = pd.Series(range(9), index=index)

     
    Downsample the series into 3 minute bins and sum the values of the timestamps falling into a bin.

    series.resample('3T').sum()

     
    To include this value close the right side of the bin interval as illustrated in the example below this one.

    series.resample('3T', label='right').sum()


    Downsample the series into 3 minute bins as above, but close the right side of the bin interval.

    series.resample('3T', label='right', closed='right').sum()


    Upsample the series into 30 second bins.

    series.resample('30S').asfreq()

     
    Upsample the series into 30 second bins and fill the NaN values using the pad method.

    series.resample('30S').pad()

     
    Upsample the series into 30 second bins and fill the NaN values using the bfill method.

    series.resample('30S').bfill()

     
    Pass a custom function via apply

    def custom_resampler(array_like):
        return np.sum(array_like)+5
    
    series.resample('3T').apply(custom_resampler)

     
    附:常见时间频率
    A year
    M month
    W week
    D day
    H hour
    T minute
    S second

  • 相关阅读:
    招隐-古琴曲-山中鸣琴,万籁声沉沉,何泠泠!
    因循苟且逸豫而无为,可以侥幸一时,而不可以旷日持久。——王安石
    模糊理论在图像处理中的应用
    铁关-中国首都警官合唱团-歌词
    听着总感觉莫名熟悉的音乐汇总
    石鼓歌-韩愈
    唐长安城
    唐长安的信仰——读书笔记
    Eclipse安装java web插件
    Java调用MySql数据库函数
  • 原文地址:https://www.cnblogs.com/dadadechengzi/p/7097836.html
Copyright © 2011-2022 走看看