[R] read "4-jan-02" as date

bogdan romocea br44114 at yahoo.com
Mon Oct 11 17:04:07 CEST 2004

Dear R users,

I have a column with dates (character) in a data frame:
12-Jan-01 11-Jan-01 10-Jan-01 9-Jan-01  8-Jan-01  5-Jan-01
and I need to convert them to (Julian) dates so that I can
sort the whole data frame by date. I thought it would be
very simple, but after checking the documentation and the
list I still don't have something that works.

1. as.Date returns the error below. What am I doing wrong?
As far as I can see the character strings are in standard
d$Date <- as.Date(d$Date, format="%d-%b-%y")
Error in fromchar(x) : character string is not in a
standard unambiguous format

2. as.date {Survival} produces this error,
d$Date <- as.date(d$Date, order = "dmy")
Error in as.date(d$Date, order = "dmy") : Cannot coerce to
date format

3. Assuming all else fails, is there a text function
similar to SCAN in SAS? Given a string like "9-Jan-01" and
"-" as separator, I'd like a function that can read the
first, second and third values (9, Jan, 01), so that I can
get Julian dates with mdy.date {survival}.

Thanks in advance,

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