• 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:
    深入理解java异常处理机制
    i2c总线
    运行时类型识别(RTTI)
    bcg界面库总结
    c++ 虚函数表
    宽字符,宽字符串
    c++异常处理
    内存管理
    c++中使用联合体
    MFC自定义消息
  • 原文地址:https://www.cnblogs.com/dadadechengzi/p/7097836.html
Copyright © 2020-2023  润新知