问题
I've some problems with my data frame in R. My data frame looks something like this:
ID TIME DAY URL_NAME VALUE TIME_SPEND
1 12:15 Monday HOME 4 30
1 13:15 Tuesday CUSTOMERS 5 21
1 15:00 Thursday PLANTS 8 8
1 16:21 Friday MANAGEMENT 1 6
....
So, I want to write the rows, containing the same "ID" into one single row. Looking something like this:
ID TIME DAY URL_NAME VALUE TIME_SPEND TIME1 DAY1 URL_NAME1 VALUE1 TIME_SPEND1 TIME2 DAY2 URL_NAME2 VALUE2 TIME_SPEND2 TIME3 DAY3 URL_NAME3 VALUE3 TIME_SPEND3
1 12:15 Monday HOME 4 30 13:15 Tuesday CUSTOMERS 5 21 15:00 Thursday PLANTS 8 8 16:21 Friday MANAGEMENT 1 6
My second problem is, that there are about 1.500.00 unique IDs and i would like to do this for the whole data frame.
I did not find any solution fitting to my problem. I would be happy about any solutions or links to handle my problem.
回答1:
I'd recommend using dcast from the "data.table" package, which would allow you to reshape multiple measure variables at once.
Example:
library(data.table)
as.data.table(mydf)[, dcast(.SD, ID ~ rowid(ID), value.var = names(mydf)[-1])]
# ID TIME_1 TIME_2 TIME_3 DAY_1 DAY_2 DAY_3 URL_NAME_1 URL_NAME_2 URL_NAME_3 VALUE_1 VALUE_2
# 1: 1 12:15 13:15 15:00 Monday Tuesday Thursday HOME CUSTOMERS PLANTS 4 5
# 2: 2 14:15 10:19 NA Tuesday Monday NA CUSTOMERS CUSTOMERS NA 2 9
# VALUE_3 TIME_SPEND_1 TIME_SPEND_2 TIME_SPEND_3
# 1: 8 30 19 40
# 2: NA 21 8 NA
Here's the sample data used:
mydf <- data.frame(
ID = c(1, 1, 1, 2, 2),
TIME = c("12:15", "13:15", "15:00", "14:15", "10:19"),
DAY = c("Monday", "Tuesday", "Thursday", "Tuesday", "Monday"),
URL_NAME = c("HOME", "CUSTOMERS", "PLANTS", "CUSTOMERS", "CUSTOMERS"),
VALUE = c(4, 5, 8, 2, 9),
TIME_SPEND = c(30, 19, 40, 21, 8)
)
mydf
# ID TIME DAY URL_NAME VALUE TIME_SPEND
# 1 1 12:15 Monday HOME 4 30
# 2 1 13:15 Tuesday CUSTOMERS 5 19
# 3 1 15:00 Thursday PLANTS 8 40
# 4 2 14:15 Tuesday CUSTOMERS 2 21
# 5 2 10:19 Monday CUSTOMERS 9 8
来源：https://stackoverflow.com/questions/41260102/merging-multiple-rows-into-single-row