[R] Where is gdata?

[Gabor Grothendieck]

On Mon, Nov 29, 2010 at 3:44 AM, Stephen Liu <satimis at yahoo.com> wrote:
> Hi Liviu,
>
>> Not if you
>> library(gdata)
>> first. Then
>> ?read.xls
>
>> should work.
>
> Yes, I did.
>
>
> I found something strange here which I can't explain.
>
> Win 7 64bit
> R 32/64 bit
>
> Just rebooted Win 7 and R
>
>> library(gdata)
> gdata: Unable to locate valid perl interpreter
> gdata:
> gdata: read.xls() will be unable to read Excel XLS and XLSX files
> gdata: unless the 'perl=' argument is used to specify the location of a
> gdata: valid perl intrpreter.
> gdata:
> gdata: (To avoid display of this message in the future, please ensure
> gdata: perl is installed and available on the executable search path.)
> gdata: Unable to load perl libaries needed by read.xls()
> gdata: to support 'XLX' (Excel 97-2004) files.
>
> gdata: Unable to load perl libaries needed by read.xls()
> gdata: to support 'XLSX' (Excel 2007+) files.
>
> gdata: Run the function 'installXLSXsupport()'
> gdata: to automatically download and install the perl
> gdata: libaries needed to support Excel XLS and XLSX formats.
>
> Attaching package: 'gdata'
>
> The following object(s) are masked from 'package:utils':
>
>     object.size

This is just a message that it can't find perl.  If you don't need to
use read.xls then you don't need perl so you can  ignore the message.
If you do need to use read.xls then install perl and once you have
done that then run installXLSXsupport().

>
>
> It complains.
>
>
>> ?read.xls
> starting httpd help server ... done
>
> "Read Excel files"
>
>
> Both 32 and 64 bit R worked.
>
>
> If there is NO complaint on running;
>
>> library(gdata)
>
> Then
>> ?read.xls
>
> can't work.

Can you clarify when ?read.xls works for you and when it does not?

>
>
> Perl seems has been installed.  But I can't recall, when and how;
>
> C:\>dir C:\Users\satimiswin764\Documents\R\win-library\2.12\gdata\
> .....
> 11/22/2010  10:44 AM    <DIR>          perl
> 11/22/2010  10:44 AM    <DIR>          R
> 11/22/2010  10:44 AM    <DIR>          unitTests
> 11/22/2010  10:44 AM    <DIR>          xls


The gdata\perl folder contains perl libraries that come with gdata.
Perl itself is not distributed with gdata and you don't need perl at
all to use gdata except for read.xls and related functions.

My understanding is that this question has nothing to do with perl nor
with read.xls and that the problem is that you seem to be able to run
this:

library(gdata)
?read.xls

and sometimes it works and at other times it does not work.  Is that
right?  Does it occur with any other package?  How about removing
gdata and reinstalling it?

remove.packages("gdata")
... exit R and check if gdata has been removed ...
... restart R ...
install.packages("gdata")


-- 
Statistics & Software Consulting
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