请问如何利用pandas函数代替下列代码：def generate_time_series(start,end,t1,t2): current = start end_item = end time_delta = datetime.timedelta(days=t1,hours=t2) time_series = [current] while current < end_item: next1 = current + time_delta time_series.append(next1) current = next1 return time_series time_hour=generate_time_series(data1.loc[0]['FDT_TIME'],data1.loc[len(data1)-1]['FDT_TIME'],0,1) time_day=generate_time_series(data1.loc[0]['FDT_TIME'],data1.loc[len(data1)-1]['FDT_TIME'],1,0) def VALIDITY(timelist,thedata): datalist1=[] datalist2=[] thedata1=thedata.values for i in range(1,len(timelist)): TFlis=[] for j in range(len(thedata1)): if timelist[i-1]<=thedata1[j][2]<timelist[i]: TFlis.append(thedata1[j][6]) datalist1.append(TFlis) for i in datalist1: datalist2.append((i.count("T"))/len(i)) return datalist2 x1=[] for i in range(0,len(VALIDITY(time_hour, data1))): x1.append(i) x2=[] for i in range(0,len(VALIDITY(time_day, data1))): x2.append(i)

可以使用pandas中的日期范围函数(pd.date_range)替换generate_time_series函数，代码如下：

import pandas as pd

def VALIDITY(timelist, thedata):
    datalist1 = []
    datalist2 = []
    thedata1 = thedata.values
    for i in range(1, len(timelist)):
        TFlis = []
        for j in range(len(thedata1)):
            if timelist[i-1] <= thedata1[j][2] < timelist[i]:
                TFlis.append(thedata1[j][6])
        datalist1.append(TFlis)
    for i in datalist1:
        datalist2.append((i.count("T"))/len(i))
    return datalist2

time_hour = pd.date_range(start=data1.loc[0]['FDT_TIME'], end=data1.loc[len(data1)-1]['FDT_TIME'], freq='H')
time_day = pd.date_range(start=data1.loc[0]['FDT_TIME'], end=data1.loc[len(data1)-1]['FDT_TIME'], freq='D')
x1 = range(len(VALIDITY(time_hour, data1)))
x2 = range(len(VALIDITY(time_day, data1)))

其中pd.date_range(start, end, freq)可以生成指定范围和频率的时间序列。具体用法可以查看pandas官方文档。