R中每秒处理时间序列数据

Process time series data for each second in R

我的数据如下所示:

# Data Sample
Time                Price    V1           Time2 V2
2016-06-20 05:09:44 2086.50   1 05:09:44.284670 -1
2016-06-20 05:09:45 2086.75   5 05:09:45.212413  1
2016-06-20 05:09:45 2086.75  10 05:09:45.212413  1
2016-06-20 05:09:45 2086.75   1 05:09:45.212413  1
2016-06-20 05:09:46 2086.75   1 05:09:46.745124  1
2016-06-20 05:09:46 2086.75   1 05:09:46.745124  1
2016-06-20 05:09:46 2086.75   1 05:09:46.819954  1
2016-06-20 05:09:49 2086.75   1 05:09:49.279392  1
2016-06-20 05:09:49 2086.75   1 05:09:49.279392  1
2016-06-20 05:09:49 2086.75   1 05:09:49.352346  1
2016-06-20 05:09:49 2086.50   2 05:09:49.964023 -1
2016-06-20 05:09:49 2086.50   1 05:09:49.964023 -1
2016-06-20 05:09:55 2086.50   1 05:09:55.343324 -1
2016-06-20 05:09:57 2086.75   1 05:09:57.551886  1
2016-06-20 05:09:57 2086.75   1 05:09:57.650549  1
2016-06-20 05:09:57 2086.75   1 05:09:57.654352  1
2016-06-20 05:09:57 2086.75   1 05:09:57.654352  1
2016-06-20 05:09:57 2086.75   1 05:09:57.726578  1

我想清理数据,以便在每一秒内对所有 V1 求和。 所以我想要的输出看起来像:

# Desired Example
Time                V1    
2016-06-20 05:09:44  1 
2016-06-20 05:09:45 16
2016-06-20 05:09:46  3
2016-06-20 05:09:47  0
2016-06-20 05:09:48  0
2016-06-20 05:09:49  6
2016-06-20 05:09:50  0
2016-06-20 05:09:51  0
2016-06-20 05:09:52  0
2016-06-20 05:09:53  0
2016-06-20 05:09:54  0
2016-06-20 05:09:55  1
2016-06-20 05:09:56  0
2016-06-20 05:09:57  5

我将第 "Time" 列转换为字符并将它们拆分并在列表中处理它们。但是,数据很大,计算时间太长。有没有办法通过动物园中的某些功能来做到这一点?

下面是使用 dput 的类似数据集:

结构(列表(V3 = c(2086.5, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.5, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75, 2086.75), V4 = c(1L, 5L, 10L, 1L, 6L, 8L, 1L, 4L, 6L, 2L, 8L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 8L, 1L, 1L, 1L, 4L, 2L, 1L, 1L, 1L, 1L, 1L, 1L), V6 = c("05:09:44.284670", "05:09:45.212413", "05:09:45.212413", "05:09:45.212413", "05:09:45.212413", "05:09:45.299104", "05:09:45.299104", "05:09:45.301513", "05:09:45.301513", "05:09:45.389110", "05:09:45.392840", "05:09:45.475688", "05:09:45.543980", "05:09:46.745124", "05:09:46.745124", "05:09:46.819954", "05:09:49.279392", "05:09:49.279392", "05:09:49.352346", "05:09:49.964023", "05:09:49.964023", "05:09:49.964023", "05:09:49.964023", "05:09:55.343324", "05:09:57.551886", "05:09:57.650549", "05:09:57.654352", "05:09:57.654352", "05:09:57.726578", "05:09:57.728848", "05:09:58.286788", "05:10:00.390708", "05:10:00.473617", "05:10:00.494903", "05:10:00.564042", "05:10:08.24907", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.633247", "05:10:09.830544", "05:10:09.924001", "05:10:09.924001", "05:10:09.924001", “05:10:09.924001”,“05:10:09.924001”),V7 = c(-1L,1L,1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, -1L, -1L, -1L, -1L, -1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, -1L, 1L, 1L, 1L, 1L, 1L, 1L)), .Names = c("V3", "V4", "V6", "V7"), row.names = c(NA, 50L), class = "data.frame")

data.table 非常快。尝试:

library(data.table)
library(lubridate)

mydata<-data.table(mydata)
mydata$Time<-ymd_hms(mydata$Time)
setkey(mydata, Time)

mydata.summed<-mydata[, .(V1 = sum(V1)), by = Time] # sums by each second

mydata2<-data.table(Time = seq(min(mydata$Time), max(mydata$Time), by = 1))
#create a new data.table to fill in the seconds you do not have values for

mydata<-mydata.summed[mydata2]
#merge them. see ?data.table for more information here

mydata[is.na(mydata)]<-0
#change the NAs that were created by the merge to 0

head(mydata, 10)

                  Time V1
1: 2016-06-20 05:09:44  1
2: 2016-06-20 05:09:45 16
3: 2016-06-20 05:09:46  3
4: 2016-06-20 05:09:47  0
5: 2016-06-20 05:09:48  0
6: 2016-06-20 05:09:49  6
7: 2016-06-20 05:09:50  0
8: 2016-06-20 05:09:51  0
9: 2016-06-20 05:09:52  0
10: 2016-06-20 05:09:53  0