Styjun

I'm trying to figure out the way of creating sequence of dates and time in this format: 2018-01-01 01:00 till 2018-03-30 01:00
for each Patient and fill the new empty value with random numbers.

My data look like :

Patients temperature 
Patient1 37 
Patient2 36
Patient3 35.4

I want to get the data looks like

Patients temperature Time 
Patient1 37 2018-01-01 01:00
Patient2 36 2018-01-01 01:00
Patient3 35.4 2018-01-01 01:00
Patient1 NA 2018-01-01 02:00
Patient2 NA 2018-01-01 02:00
Patient3 NA 2018-01-01 02:00
Patient1 NA 2018-01-01 03:00
Patient2 NA 2018-01-01 03:00
Patient3 NA 2018-01-01 03:00

So the Time variable will be till 2018-03-30 01:00 and the temperature can be NA and then I generate random numbers but not repeating the same values of the temperature of each Patient.

I tried this commands but didn't work and I don't know how to assign the time to each Patient

Time <- seq (from=as.POSIXct("2018-1-1 01:00"), to=as.POSIXct("2018-3-30 01:00", tz="UTC"), by="hour")

And I tried too this command but I got error message:

dt = data.table(ID = Sensor7$StationID,Time = seq (from=as.POSIXct("2018-01-01 02:00"), to=as.POSIXct("2018-03-30 01:00",format = "%Y-%m-%d %H:%M",by="hour")))

But it gave me error message:

Error in seq.POSIXt(from = as.POSIXct("2018-01-01 00:00"), to = as.POSIXct("2018-03-30 23:00", : 
 exactly two of 'to', 'by' and 'length.out' / 'along.with' must be specified

Does anyone have any idea how to get the data in the format I'm looking for pleas?

You weren't too far off. Try this:

# I reproduce your data:

library(data.table)
data = data.table::fread(input = 
"Patients,temperature 
Patient1,37 
Patient2,36
Patient3,35.4")

library(dplyr)

Time <- seq (from=as.POSIXct("2018-1-1 01:00"), to=as.POSIXct("2018-3-30 01:00", tz="UTC"), by="hour")

And this should do what you want:

data %>% 
 group_by(Patients) %>% 
 do(data.frame("temperature" = c(.data$temperature, rep(NA,length(Time) - nrow(.data))), Time))

Here's one way:

dat = data.frame(Patients=paste0("Patients", 1:3), temperature=c(37,36,35.4))

Time = seq(as.POSIXct("2018-01-01 01:00"), as.POSIXct("2018-03-30 01:00"), by="hour")

new.data = data.frame(
 Patient = rep(dat$Patients, each=length(Time)),
 Time = rep(Time, length(dat$Patients))
)

I'm not sure how you want to generate the random values, but here's a generic method:

new.data$Random.Temperature = rnorm(nrow(new.data), 35, 1)