About chron time matching in r

Question

I try to match two files by using the time column in r. Therefore, I choose chron time to achieve this. But when I try to convert the 'Time' column to chron time, I got the warning message that 'In convert.dates(dates., format = format[[1]], origin. = origin.): 331 months out of range set to NA' my data are as follows,

  Year Month Day Rain_mm                Time           chrontime
1   2019     1   1     0.6 01/01/2019 01:10:00 (01/01/19 01:10:00)
2   2019     1   2     0.0 02/01/2019 01:10:00 (02/01/19 01:10:00)
3   2019     1   3     0.0 03/01/2019 01:10:00 (03/01/19 01:10:00)
4   2019     1   4     0.0 04/01/2019 01:10:00 (04/01/19 01:10:00)
5   2019     1   5     0.0 05/01/2019 01:10:00 (05/01/19 01:10:00)
6   2019     1   6     0.0 06/01/2019 01:10:00 (06/01/19 01:10:00)
7   2019     1   7     3.4 07/01/2019 01:10:00 (07/01/19 01:10:00)
8   2019     1   8     5.8 08/01/2019 01:10:00 (08/01/19 01:10:00)
9   2019     1   9     0.4 09/01/2019 01:10:00 (09/01/19 01:10:00)
10  2019     1  10     0.0 10/01/2019 01:10:00 (10/01/19 01:10:00)
11  2019     1  11     0.2 11/01/2019 01:10:00 (11/01/19 01:10:00)
12  2019     1  12     2.8 12/01/2019 01:10:00 (12/01/19 01:10:00)
13  2019     1  13     2.6 13/01/2019 01:10:00             (NA NA)
14  2019     1  14     2.2 14/01/2019 01:10:00             (NA NA)
15  2019     1  15     3.2 15/01/2019 01:10:00             (NA NA)
16  2019     1  16     6.2 16/01/2019 01:10:00             (NA NA)
17  2019     1  17    12.6 17/01/2019 01:10:00             (NA NA)
18  2019     1  18     0.0 18/01/2019 01:10:00             (NA NA)
19  2019     1  19     0.0 19/01/2019 01:10:00             (NA NA)
20  2019     1  20     0.0 20/01/2019 01:10:00             (NA NA)
21  2019     1  21     7.4 21/01/2019 01:10:00             (NA NA)
22  2019     1  22     0.2 22/01/2019 01:10:00             (NA NA)
23  2019     1  23     0.0 23/01/2019 01:10:00             (NA NA)
24  2019     1  24     0.0 24/01/2019 01:10:00             (NA NA)
25  2019     1  25     0.0 25/01/2019 01:10:00             (NA NA)
26  2019     1  26     0.6 26/01/2019 01:10:00             (NA NA)
27  2019     1  27     7.6 27/01/2019 01:10:00             (NA NA)
28  2019     1  28     1.6 28/01/2019 01:10:00             (NA NA)
29  2019     1  29     0.0 29/01/2019 01:10:00             (NA NA)
30  2019     1  30     0.0 30/01/2019 01:10:00             (NA NA)
31  2019     1  31     0.0 31/01/2019 01:10:00             (NA NA)
32  2019     2   1     0.0 01/02/2019 01:10:00 (01/02/19 01:10:00)
33  2019     2   2     0.6 02/02/2019 01:10:00 (02/02/19 01:10:00)
34  2019     2   3     0.0 03/02/2019 01:10:00 (03/02/19 01:10:00)
35  2019     2   4     1.0 04/02/2019 01:10:00 (04/02/19 01:10:00)
36  2019     2   5     0.2 05/02/2019 01:10:00 (05/02/19 01:10:00)
37  2019     2   6     3.6 06/02/2019 01:10:00 (06/02/19 01:10:00)
38  2019     2   7     1.8 07/02/2019 01:10:00 (07/02/19 01:10:00)
39  2019     2   8     3.0 08/02/2019 01:10:00 (08/02/19 01:10:00)
40  2019     2   9     6.8 09/02/2019 01:10:00 (09/02/19 01:10:00)
41  2019     2  10     3.4 10/02/2019 01:10:00 (10/02/19 01:10:00)
42  2019     2  11     0.6 11/02/2019 01:10:00 (11/02/19 01:10:00)
43  2019     2  12     0.0 12/02/2019 01:10:00 (12/02/19 01:10:00)
44  2019     2  13     0.0 13/02/2019 01:10:00             (NA NA)
45  2019     2  14     0.0 14/02/2019 01:10:00             (NA NA)
46  2019     2  15     0.0 15/02/2019 01:10:00             (NA NA)
......

my codes are:

Dts <- with(DMIdata, paste(substring(Time, 1,2), substring(Time,4,5), substring(Time, 9, 10), sep='/'))    
hrs <- with(DMIdata, substring(Time, 13, 20))
DMIdata$chrontime <- chron(Dts,hrs)

I was wondering why all the dates after the 13th are set to NA in the chronic transformation? And how to improve my codes to make it work?

Thanks for any help!

akrun · Accepted Answer · 2020-08-01T17:35:12.530

library(chron)

The issue with substring is that the order chron expects for Date to be certain format specified in the ?chron

format - The dates format can be any permutation of the characters "d", "m", or "y" delimited by a separator (possibly null), e.g., "m/d/y", "d-m-y", "ymd", are all valid; the format can also be permutations of the words "day", "month" and "year" (with non-null separator), which produces the month name, e.g., "month day year" produces "April 20 1992", "day mon year" produces "20 Apr 1992".

By default, if we look at the Usage, it is mdy

chron(dates., times., format = c(dates = "m/d/y", times = "h:m:s"), out.format, origin.)

while the OP's Dts are in d/m/y. We could specify the format here

chron(Dts,hrs, format = c(dates = "d/m/y", times = "h:m:s"))
#[1] (01/01/19 01:10:00) (02/01/19 01:10:00) (03/01/19 01:10:00) (04/01/19 01:10:00) (05/01/19 01:10:00) (06/01/19 01:10:00)
#[7] (07/01/19 01:10:00) (08/01/19 01:10:00) (09/01/19 01:10:00) (10/01/19 01:10:00) (11/01/19 01:10:00) (12/01/19 01:10:00)
#[13] (13/01/19 01:10:00) (14/01/19 01:10:00) (15/01/19 01:10:00) (16/01/19 01:10:00) (17/01/19 01:10:00) (18/01/19 01:10:00)
#[19] (19/01/19 01:10:00) (20/01/19 01:10:00) (21/01/19 01:10:00) (22/01/19 01:10:00) (23/01/19 01:10:00) (24/01/19 01:10:00)
#[25] (25/01/19 01:10:00) (26/01/19 01:10:00) (27/01/19 01:10:00) (28/01/19 01:10:00) (29/01/19 01:10:00) (30/01/19 01:10:00)
#[31] (31/01/19 01:10:00) (01/02/19 01:10:00) (02/02/19 01:10:00) (03/02/19 01:10:00) (04/02/19 01:10:00) (05/02/19 01:10:00)
#[37] (06/02/19 01:10:00) (07/02/19 01:10:00) (08/02/19 01:10:00) (09/02/19 01:10:00) (10/02/19 01:10:00) (11/02/19 01:10:00)
#[43] (12/02/19 01:10:00) (13/02/19 01:10:00) (14/02/19 01:10:00) (15/02/19 01:10:00)

data

DMIdata <- structure(list(Year = c(2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 
2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 
2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 
2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 
2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 
2019L, 2019L, 2019L, 2019L), Month = c(1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), Day = c(1L, 2L, 3L, 4L, 5L, 
6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L, 15L, 16L, 17L, 18L, 
19L, 20L, 21L, 22L, 23L, 24L, 25L, 26L, 27L, 28L, 29L, 30L, 31L, 
1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L, 
15L), Rain_mm = c(0.6, 0, 0, 0, 0, 0, 3.4, 5.8, 0.4, 0, 0.2, 
2.8, 2.6, 2.2, 3.2, 6.2, 12.6, 0, 0, 0, 7.4, 0.2, 0, 0, 0, 0.6, 
7.6, 1.6, 0, 0, 0, 0, 0.6, 0, 1, 0.2, 3.6, 1.8, 3, 6.8, 3.4, 
0.6, 0, 0, 0, 0), Time = c("01/01/2019 01:10:00", "02/01/2019 01:10:00", 
"03/01/2019 01:10:00", "04/01/2019 01:10:00", "05/01/2019 01:10:00", 
"06/01/2019 01:10:00", "07/01/2019 01:10:00", "08/01/2019 01:10:00", 
"09/01/2019 01:10:00", "10/01/2019 01:10:00", "11/01/2019 01:10:00", 
"12/01/2019 01:10:00", "13/01/2019 01:10:00", "14/01/2019 01:10:00", 
"15/01/2019 01:10:00", "16/01/2019 01:10:00", "17/01/2019 01:10:00", 
"18/01/2019 01:10:00", "19/01/2019 01:10:00", "20/01/2019 01:10:00", 
"21/01/2019 01:10:00", "22/01/2019 01:10:00", "23/01/2019 01:10:00", 
"24/01/2019 01:10:00", "25/01/2019 01:10:00", "26/01/2019 01:10:00", 
"27/01/2019 01:10:00", "28/01/2019 01:10:00", "29/01/2019 01:10:00", 
"30/01/2019 01:10:00", "31/01/2019 01:10:00", "01/02/2019 01:10:00", 
"02/02/2019 01:10:00", "03/02/2019 01:10:00", "04/02/2019 01:10:00", 
"05/02/2019 01:10:00", "06/02/2019 01:10:00", "07/02/2019 01:10:00", 
"08/02/2019 01:10:00", "09/02/2019 01:10:00", "10/02/2019 01:10:00", 
"11/02/2019 01:10:00", "12/02/2019 01:10:00", "13/02/2019 01:10:00", 
"14/02/2019 01:10:00", "15/02/2019 01:10:00")), class = "data.frame", row.names = c("1", 
"2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", 
"14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", 
"25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35", 
"36", "37", "38", "39", "40", "41", "42", "43", "44", "45", "46"
))

@Alice the issue seems to be with the `format` for `Date` part as it can only match certain formats — akrun, Aug 01 '20 at 17:28
@Alice updated the post with the explanation why it didn't work for you — akrun, Aug 01 '20 at 17:31

About chron time matching in r

1 Answers1

data