Question

我是R的新手，所以需要对我正在尝试编码的问题提供一些帮助。下面是一个数据集，我需要计算自警报以来的天数。我有时间序列数据，其中每秒捕获值，并且在第10秒发生警报。我想计算从第10秒到第1秒的时间之间的差异，并在几小时内将其填入单独的列中。一旦第一个警报的值为0，即差值为零，下一行应考虑下一个警报并填充警报后的天数。下面是样本数据

PIT >> WARNING : Slave exited abnormally due to TIMED_OUT

感谢。

Answer 1

DF<-read.table(text="datetime,alarm
1/1/2015 0:00,NO
1/1/2015 0:01,NO
1/1/2015 0:02,NO
1/1/2015 0:03,NO
1/1/2015 0:04,NO
1/1/2015 0:05,NO
1/1/2015 0:06,NO
1/1/2015 0:07,NO
1/1/2015 0:08,NO
1/1/2015 0:09,NO
1/1/2015 0:10,YES
1/1/2015 0:11,NO
1/1/2015 0:12,NO
1/1/2015 0:13,NO
1/1/2015 0:14,YES
1/1/2015 0:15,NO
1/1/2015 0:16,NO
1/1/2015 0:17,NO",header=TRUE,sep=",")

library(data.table)
setDT(DF)
#create grouping variable
DF[, period := rev(cumsum(rev(alarm == "YES")))]

DF[, datetime := as.POSIXct(datetime, "%m/%d/%Y %H:%M", tz = "UTC")]

#split-apply-combine operation
Res <- DF[, .(start = min(datetime),
       end = max(datetime)),
   by = period]

#possibly you need to add a minute here, don't know from your description    
Res[, length := difftime(end, start, unit = "hour")]

Res[, period := max(period) - period + 1]
#   period               start                 end           length
#1:      1 2015-01-01 00:00:00 2015-01-01 00:10:00 0.16666667 hours
#2:      2 2015-01-01 00:11:00 2015-01-01 00:14:00 0.05000000 hours
#3:      3 2015-01-01 00:15:00 2015-01-01 00:17:00 0.03333333 hours

Answer 2

config.logger = Logger.new(STDOUT)
config.logger.level = Logger.const_get('INFO')
config.log_level = :info

创建一个值以在R中显示事件的时间

2 个答案: