Increment date for times after midnight [closed]

1
votes

I got this dataframe:

       bedtime           waketime
 2021-01-01 21:55:00  2021-01-02 09:00:00
 2021-01-02 00:15:00  2021-01-03 08:45:00
 2021-01-03 01:05:00  2021-01-04 08:40:00
 2021-01-04 02:01:00  2021-01-05 10:50:00
 2021-01-05 00:20:00  2021-01-06 08:45:00
 2021-01-06 02:25:00  2021-01-07 10:55:00
 2021-01-07 00:25:00  2021-01-08 06:45:00
 2021-01-08 00:10:00  2021-01-09 09:15:00
 2021-01-09 00:20:00  2021-01-10 08:15:00
 2021-01-10 00:00:00  2021-01-11 08:45:00

I want to change the date for the times after midnight (+ 1 day).

I did this with a different dataframe before with this code and it worked perfectly

df[hour(df$bedtime) < 12, "bedtime"] <- df$bedtime[hour(df$bedtime) < 12, "bedtime"] + (24*60*60)

But now I got the error "Incorrect number of dimensions".

I dont't know whats wrong with this dataframe, the variables have the same type than the others.

1
rdataframedatetimetime
Try : df[hour(df$bedtime) < 12, "bedtime"] <- df[hour(df$bedtime) < 12, "bedtime"] + (24*60*60) – Ronak Shah
Yes thats what I already tried, but the error occurs – psycho95
How do you build the dataframe? Have you got any code which can be used to reproduce the df shown in your example? – BillyBouw
Oh yes, my bad! Thank your very much, this worked! The only problem is that it doesn't work, if the dataframe contains NAs. If I can't remove those cases because they contain other important information, how can I handle this? – psycho95

1 Answers

1
votes

Try this one using which, which frees you from the NA issue.

d[] <- lapply(d, as.POSIXct)  ## first transform to POSIX if isn't yet
d <- transform(d, bedtime.old=bedtime, waketime.old=waketime)  ## copy for demonstration

ix <- which(strftime(d$bedtime, "%H") < 12)
d[ix, "bedtime"] <- d[ix, "bedtime"] + 24*60*60
d
#                bedtime            waketime         bedtime.old        waketime.old
# 1  2021-01-01 21:55:00 2021-01-02 09:00:00 2021-01-01 21:55:00 2021-01-02 09:00:00
# 2  2021-01-03 00:15:00 2021-01-03 08:45:00 2021-01-02 00:15:00 2021-01-03 08:45:00
# 3  2021-01-04 01:05:00 2021-01-04 08:40:00 2021-01-03 01:05:00 2021-01-04 08:40:00
# 4  2021-01-05 02:01:00 2021-01-05 10:50:00 2021-01-04 02:01:00 2021-01-05 10:50:00
# 5  2021-01-06 00:20:00 2021-01-06 08:45:00 2021-01-05 00:20:00 2021-01-06 08:45:00
# 6  2021-01-07 02:25:00                <NA> 2021-01-06 02:25:00                <NA>
# 7  2021-01-08 00:25:00 2021-01-08 06:45:00 2021-01-07 00:25:00 2021-01-08 06:45:00
# 8  2021-01-09 00:10:00 2021-01-09 09:15:00 2021-01-08 00:10:00 2021-01-09 09:15:00
# 9                 <NA> 2021-01-10 08:15:00                <NA> 2021-01-10 08:15:00

Data:

d <- structure(list(bedtime = c("2021-01-01 21:55:00", "2021-01-02 00:15:00", 
"2021-01-03 01:05:00", "2021-01-04 02:01:00", "2021-01-05 00:20:00", 
"2021-01-06 02:25:00", "2021-01-07 00:25:00", "2021-01-08 00:10:00", 
NA, "2021-01-10 00:00:00"), waketime = c("2021-01-02 09:00:00", 
"2021-01-03 08:45:00", "2021-01-04 08:40:00", "2021-01-05 10:50:00", 
"2021-01-06 08:45:00", NA, "2021-01-08 06:45:00", "2021-01-09 09:15:00", 
"2021-01-10 08:15:00", "2021-01-11 08:45:00")), class = "data.frame", row.names = c(NA, 
-10L))