Following is part of my data:
Date Elev Temp.C
1 02 January 2010 200 14.7
2 02 January 2010 300 5
3 02 January 2010 500 -2
4 02 January 2010 1000 -9.8
5 02 January 2010 2000 -7.1
I wanted to change the format of the date in to 2010-01-01 or "%Y-%m-%d". Class of data is character and I tried as follows:
data$Date<-as.Date(data$Date,format="%d%B%Y")
data$Date<-as.Date(data[["Date"]],"%d%B%Y")
data$Date<-strptime(data$Date,"%d%B%Y")
All of the above trials are displaying <NA>in the Date column. I have another data file with date format of "%m/%d/%Y", it worked fine with strptime, but for the above data set it is not working. Any idea?
The problem is related to your locale. If you look at ?strptime, you will see:
‘%B’ Full month name in the current locale. (Also matches
abbreviated name on input.)
This means, %B is sensitive to your locale. Have a look at ?locales if you are unsure what a locale is. When I asked you about the output of Sys.getlocale("LC_TIME"), you said you got "English_United States.1252". Now let's first change your locale:
Sys.setlocale("LC_TIME", "C")
Then do:
as.Date("02 January 2010", "%d %B %Y")
# [1] "2010-01-02"
Note, since there is an empty space between "02", "January" and "2010", you need to leave an empty space between %d, %B, %Y. So, don't use "%d%B%Y" as put in your post, but use "%d %B %Y".