R中的简单时间间隔 [英] Simple time interval in R

问题描述

我的ts具有以下属性:

I've got a ts with the following properties:

summary(Y$Date)
                Min.               1st Qu.                Median                  Mean               3rd Qu.                  Max. 
"2001-01-01 05:30:00" "2004-03-15 10:40:30" "2007-01-03 04:00:00" "2006-11-11 15:53:11" "2009-08-13 12:00:00" "2011-12-30 12:30:00" 

str(Y$Date)
POSIXlt[1:174110], format: "2001-01-01 12:00:00" "2001-01-01 05:30:00" "2001-01-02 01:30:00" "2001-01-02 02:00:00" "2001-01-02 02:00:00" "2001-01-02 02:01:00" "2001-01-02 04:00:00" "2001-01-02 04:00:00" ...

length(Y$Date)
[1] 174110

Y$Date[1:5] 
[1] "2001-01-01 12:00:00" "2001-01-01 05:30:00" "2001-01-02 01:30:00" "2001-01-02 02:00:00" "2001-01-02 02:00:00"

我正在寻找一种创建时间间隔的简单方法，该时间间隔显示与以下结果相同的结果:

I am looking for a simple way to create a time interval which presents the same result as:

Y$Date[grep("2001",Y$Date)]

仅以以下形式提取2001年的所有值:

which extracts all values from 2001, only in the form of:

Y$Date["2001" =< Y$Date < "2002"] #or
Y$Date["2001" =< Y$Date & Y$Date < "2002"] #for that matter.

因为它可以让我设置时间间隔，例如从2001年到2005年等.

As it would allow me to set time intervals such as from 2001 - 2005 etc.

键入:

Y$Date[Y$Date < "2002"] 

R调整整个序列的结果.我已经使用cut()将ts分为几个间隔:

results in R retuning the entire series.I have already split the ts into several intervals using cut():

y<-cut(Y$Date,breaks="year") #and
as.data.frame(table(y))

两者都做得很好，但确实为我提供了所需的灵活性.

both do a pretty good job, but do provide me with the level of flexibility that I want.

非常感谢您的帮助，如果可以以任何方式帮助您解决此问题，请告诉我.

Your help is very much appreciated, please let me know if I can assist you in any way to resolve this issue.

非常感谢您.

推荐答案

将日期转换为xts类对象请看library(xts)中?xts的示例:

convert the date to xts class objects look at the example of ?xts in library(xts):

date <- as.xts(Y$Date, descr='my new xts object')

现在，您可以提取以下格式的时间间隔(取自?xts):

Now you can extract time intervals in the following format (taken from ?xts):

date['2007']  # all of 2007
date['2007-03/']  # March 2007 to the end of the data set
date['2007-03/2007']  # March 2007 to the end of 2007
date['/'] # the whole data set
date['/2007'] # the beginning of the data through 2007
date['2007-01-03'] # just the 3rd of January 2007

这篇关于R中的简单时间间隔的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！