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Question

I have a data frame containing dates as characters , dd.mm.yyyy format. want to convert those in date class, format yyyy-md . as.date() is not working returning error, do not know how to convert 'dates' to class “Date”

dates <- data.frame(cbind(c("5.1.2015", "6.1.2014", "17.2.2014", "28.10.2014")))
colnames(dates) <- c("dates")
as.Date(dates, format = "%Y-%m-%d")

new_format_dates <- cbind(gsub("[[:punct:]]", "", dates[1:nrow(dates),1]))
as.Date(new_format_dates, format = "%Y-%m-%d")

So I tried to replace the . and reformat those dates under new_format_dates , returning result like [1] NA NA NA NA

Answer 1

Firstly, make your data.frames properly; don't use cbind in data.frame . Next, set the format argument of as.Date to the format you've got, including separators. If you don't know the symbol you need, check out ?strptime .

dates <- data.frame(dates = c("5.1.2015", "6.1.2014", "17.2.2014", "28.10.2014"))
dates$dates_new <- as.Date(dates$dates, format = "%d.%m.%Y")
dates
#        dates  dates_new
# 1   5.1.2015 2015-01-05
# 2   6.1.2014 2014-01-06
# 3  17.2.2014 2014-02-17
# 4 28.10.2014 2014-10-28

Answer 2

dates <- data.frame(cbind(c("5.1.2015", "6.1.2014", "17.2.2014", "28.10.2014")))
colnames(dates) <- c("dates")

dates$new_Dates <- gsub("[.]","-",dates$dates) 
dates$dates <- NULL
dates_new <- as.Date(dates$new_Dates, format = "%d-%m-%Y")

dates_new <- data.frame(dates_new)
print(dates_new)