R中的循环（时间间隔）

Question

我想通过使用R语言将我的数据（时间）转换为相应的时间间隔。在如下图所示我数据框：

Date,Time,Lots,Status 
"10-28-15","00:04:13","13-09","1" 
"10-28-15","00:04:16","13-10","1" 
"10-28-15","00:04:30","13-11","1" 
"10-28-15","00:04:44","13-12","1" 
"10-28-15","00:04:48","13-13","1" 
"10-28-15","00:04:50","13-14","1" 
"10-28-15","00:04:57","13-15","0" 
"10-28-15","00:04:57","13-16","0" 
"10-28-15","00:05:04","13-17","0" 
"10-28-15","00:05:04","13-18","0" 

，我想有这样的时间间隔的输出（带有4个间隔每小时/每15分钟）

Date,Time,Lots,Status,*interval* 
"10-28-15","00:04:13","13-09","1",*"00:04:00"* 
"10-28-15","00:04:16","13-10","1","00"04"15" 
"10-28-15","00:04:30","13-11","1","00:04:30" 
"10-28-15","00:04:44","13-12","1","00:04:45" 
"10-28-15","00:04:48","13-13","1","00:04:45" 
"10-28-15","00:04:50","13-14","1","00:04:45" 
"10-28-15","00:04:57","13-15","0","00:04:45" 
"10-28-15","00:04:57","13-16","0","00:04:45" 
"10-28-15","00:05:04","13-17","0","00:05:00" 
"10-28-15","00:05:04","13-18","0","00:05:00" 

如果我使用for循环，如

for(i=0,i<=60,i+15) 
} for(if(i>i && i<=i+15) 
} 

我该如何在R语言中做到这一点？感谢您的帮助球员，新手在编程...

sample$int<- strptime(paste(sample$V1,sample$V2),format="%m-%d-%y %H:%M:%S") 
min_V2<-trunc(min(strptime("28-10-2015 00:00:20", "%d-%m-%y %H:%M:%S")),"min") 
max_V2<-trunc(max(strptime("28-10-2015 23:59:59", "%d-%m-%y %H:%M:%S")),"min") + 900 
out <- cut(sample$int, breaks = seq(min_V2, max_V2, by = "15 min")) 

Answer 1

我假设你的意思秒，不分钟在你的你想要的描述。

这里是我们如何能够从你的输入数据到15秒间隔一个基本的例子：

首先，将您的“日期”和“时间”列，以形成实际的日期/时间对象：

x <- strptime(paste(mydf$Date, mydf$Time), 
       format = "%m-%d-%y %H:%M:%S") 

其次，找出值范围内的最小值和最大值。由于看起来这些值来自同一天，但可变分钟数，我选择了“分”在截断。对于max的价值，我增加了60秒，以凑到下一分钟。

min_x <- trunc(min(x), "min") 
max_x <- trunc(max(x), "min") + 60 

第三，我们可以使用seq通过每隔15秒产生断点的序列。我们可以在cut使用这些断点：

out <- cut(x, breaks = seq(min_x, max_x, by = "15 sec")) 
out 
# [1] 2015-10-28 00:04:00 2015-10-28 00:04:15 2015-10-28 00:04:30 
# [4] 2015-10-28 00:04:30 2015-10-28 00:04:45 2015-10-28 00:04:45 
# [7] 2015-10-28 00:04:45 2015-10-28 00:04:45 2015-10-28 00:05:00 
# [10] 2015-10-28 00:05:00 
# 8 Levels: 2015-10-28 00:04:00 ... 2015-10-28 00:05:45 

第四，如果你只对时间间隔有兴趣，你可以重新格式化的cut输出为日期/时间对象，并使用format只提取小时/分钟/秒部分。

format(as.POSIXct(out), "%H:%M:%S") 
# [1] "00:04:00" "00:04:15" "00:04:30" "00:04:30" "00:04:45" "00:04:45" 
# [7] "00:04:45" "00:04:45" "00:05:00" "00:05:00"