Hi list, I have some questions regarding
1) conversion of date + time characters to chron
2) formatting chron object printing
Regarding (1), Gabor's Rnews 2004 4/1 article has been indispensible,
but I often work with files where dates and times are contained in a
single field. In this case, I would like to control input/output of
chron objects when each observation of date and time is stored as a
single string.
So here are some procedures that I've tried:
## define character vector
x <- c("07/01/2001 12:00:00","07/17/2001 15:00:00")
[1] (07/01/01 12:00:00) (07/17/01 15:00:00)
Could there be any gotchas with the third method
(as.chron(strptime(...)))? The 'tz' attribute for POSIXlt objects are
ignored, but I am not sure if there are any implications of the
'$isdst' field are for conversions. I do like this alternative for the
conciseness-flexibility tradeoff; in my experience, I have not had any
problems - but wanted to inquire if at some point the '$isdst' field (or
possibly something else) could give me trouble.
Regarding the printing of chron objects, this behavior is peculiar to me:
format(chronObj,format=c("m/d","h:m"))
[1] "(0701 1200)" "(0717 1500)"
The special characters ("/",":") are not printed - I've tried changing
the attribute of the chron object, looked at the format.chron() method
(getS3method("format","chron")), etc. and am still confused; the
chron() documentation says its specification should be similar the
input format. Could I have missed something?
Thanks!
ST