format a Date column in a Data Frame
I've the following data from a data frame
Name,JoiningDate,AmtPaid
Joe,12/31/09,1000
Amy,10/28/09,100
John,05/06/10,200
The Joining Date is coming in as a fac开发者_如何学Gotor (when I sapply
). How can I convert this to date and then sort on JoiningDate
?
This should do it (where df is your dataframe)
df$JoiningDate <- as.Date(df$JoiningDate , format = "%m/%d/%y")
df[order(df$JoiningDate ),]
try this package, works wonders, and was made for date/time...
library(lubridate)
Portfolio$Date2 <- mdy(Portfolio.all$Date2)
The data.table
package has its IDate
class and functionalities similar to lubridate
or the zoo
package. You could do:
dt = data.table(
Name = c('Joe', 'Amy', 'John'),
JoiningDate = c('12/31/09', '10/28/09', '05/06/10'),
AmtPaid = c(1000, 100, 200)
)
require(data.table)
dt[ , JoiningDate := as.IDate(JoiningDate, '%m/%d/%y') ]
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