我有一个类似于这样的数据框:
在此过程中,我还希望将“Measurement”列旋转为其各个类别的单独列,并计算每个类别的数量。 我的期望输出结果为:
我尝试了类似以下的方法来获取日期范围。
请提供一些关于此事的指导。
Datetime <- c("2015-12-31 08:30:13", "2015-12-31 12:45:00", "2016-01-01 02:53:20", "2016-01-01 03:22:18",
"2016-01-01 09:42:10", "2016-01-01 20:55:50", "2016-01-01 21:14:10", "2016-01-02 05:42:16",
"2016-01-02 08:31:15", "2016-01-02 09:13:10", "2016-01-03 00:45:14", "2016-01-03 05:56:00",
"2016-01-03 13:44:00", "2016-01-03 14:41:20", "2016-01-03 15:33:10", "2016-01-04 04:24:00",
"2016-01-04 17:24:12", "2016-01-04 17:28:16", "2016-01-04 18:22:34", "2016-01-05 02:34:31")
Measurement <- c("Length","Breadth","Height","Length",
"Breadth","Breadth","Breadth","Length",
"Length","Breadth","Height","Height",
"Height","Length","Height","Length",
"Length","Breadth","Breadth","Breadth")
df1 <- data.frame(Datetime,Measurement)
我将尝试对这种格式的日期进行子集划分
Day1 = December 31st,2015 at 6:30AM to January 1st 2016 6:30AM
Day2 = January 1st,2015 at 6:30AM to January 2nd 2016 6:30AM
etc..
在此过程中,我还希望将“Measurement”列旋转为其各个类别的单独列,并计算每个类别的数量。 我的期望输出结果为:
Days Length Breadth Height
Day1 2 1 1
Day2 1 3 0
Day3 1 1 2
Day4 2 0 2
Day5 1 3 0
我尝试了类似以下的方法来获取日期范围。
today <- as.POSIXlt(Sys.time())
today$mday <- today$mday + (today$wday-(today$wday+27))
today$hour = "6";today$min = "30";today$sec = "0"
Back1Day <- today
Back1Day$mday <- today$mday-1
如何根据这个问题进行子集。我尝试使用dcast进行操作,但是没有成功。
df2 <- dcast(df1, Datetime ~ Measurement)
请提供一些关于此事的指导。