Question

I am importing some data from NOAA and it has dates and times in separate columns. I searched for an elegant way to append a single datetime column in my R dataframe but was unable. I found a stack exchange question about the inverse but not this one. Is there a simple as.Date command I could run? I am simply using read.table for a downloaded text file and it imports just find.

Buoy data is here:
http://www.ndbc.noaa.gov/data/realtime2/51202.txt

>yr mo  dy  hr  mn  degT    m.s m.s.1   m   sec sec.1 degT.1    hPa degC    degC.1  degC.2  nmi hPa.1   ft
>2012   1   16  3   55  MM  MM  MM  1.4 10  7.2 339 MM  MM  23.9    MM  MM  MM  MM

Answer 1

You can use ISOdatetime, which is just a simple wrapper to as.POSIXct. Make sure to specify the sec argument as zero.

Data$timestamp <- with(Data, ISOdatetime(YY,MM,DD,hh,mm,0))