bug?

library(foreign)
da<-read.dta(file.choose())
da

   startdat starttim    enddate endtime days hoursmin secused
1 2005-01-11        2 2005-12-15   20.19   NA       NA       9

attributes(da)

$datalabel
[1] "Example of use of date and time functions"

$time.stamp
[1] "15 Ê®¶þÔ 2005 20"

$names
[1] "startdat" "starttim" "enddate"  "endtime"  "days"     "hoursmin" "secused"

$formats
[1] "%d"    "%5.2f" "%d"    "%5.2f" "%3.0f" "%5.2f" "%4.0f"

$types
[1] 253 255 253 255 252 255 252

write.foreign(da,"c:\\da.sps","da.txt","SPSS")

then I try to run the da.sps,some errors come.I think the write.foreign function needs some improvement.
It seems SPSS does not have such date/time data format as yyyy-mm-dd.
Here is some information about the spss date/time format.

"Date/Time. Valid values include dates of the general format dd-mm-yyyy, mm/dd/yyyy, dd.mm.yyyy, yyyy/mm/dd, hh:mm:ss, and a variety of other date and time formats. Months can be represented in digits, Roman numerals, or three-letter abbreviations, or they can be fully spelled out."

Warning # 1102
An invalid numeric field has been found.  The result has been set to the
system-missing value.

Command line: 7  Current case: 1  Current splitfile group: 1
Field contents: '2005-01-11'
Record number: 1  Starting column: 1  Record length: 37

Warning # 1102
An invalid numeric field has been found.  The result has been set to the
system-missing value.

Command line: 7  Current case: 1  Current splitfile group: 1
Field contents: '2005-12-15'
Record number: 1  Starting column: 14  Record length: 37

Warning # 1102
An invalid numeric field has been found.  The result has been set to the
system-missing value.

Command line: 7  Current case: 1  Current splitfile group: 1
Field contents: 'NA'
Record number: 1  Starting column: 31  Record length: 37

Warning # 1102
An invalid numeric field has been found.  The result has been set to the
system-missing value.

Command line: 7  Current case: 1  Current splitfile group: 1
Field contents: 'NA'
Record number: 1  Starting column: 34  Record length: 37

packageDescription("foreign")

Package: foreign
Priority: recommended
Version: 0.8-11
Date: 2005-12-08
Title: Read Data Stored by Minitab, S, SAS, SPSS, Stata, Systat, dBase,
       ...
Depends: R (>= 2.2.0)
Imports: stats, methods
Maintainer: R-core <R-core at r-project.org>
Author: R-core members, Saikat DebRoy <saikat at stat.wisc.edu>, Roger
       Bivand <Roger.Bivand at nhh.no> and others: see COPYRIGHTS file in
       the sources.
Description: Functions for reading and writing data stored by
       statistical packages such as Minitab, S, SAS, SPSS, Stata,
       Systat, ..., and for reading and writing .dbf (dBase) files.
License: GPL version 2 or later
Packaged: Fri Dec 9 14:46:20 2005; ripley
Built: R 2.2.0; i386-pc-mingw32; 2005-12-10 14:23:19; windows




2005-12-15

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Deparment of Sociology
Fudan University

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Blog:http://sociology.yculblog.com