Hi, guys, my problem is solved.
I used file.info(list.files(getwd(),full.names=TRUE)) and found out that
the said file is listed as "kim.jpg" instead of "kim.jpeg". So
kim<-readJPEG("kim.jpg") worked. Thanks for your help and sorry for my
newbie question.


On Mon, Jan 14, 2013 at 11:59 AM, Yi Yuan <lambandme@gmail.com> wrote:

> Thanks William !
>
>  file.info("E:/ home work/Rstudio/kim.jpeg")
>                                        size isdir mode mtime ctime atime
>  exe
> E:/home work/Rstudio/kim.jpeg   NA    NA <NA>  <NA>  <NA>  <NA> <NA>
>
> So R thinks this file doesn't exist? But the file is already in "E:/ home
> work/Rstudio" folder, I don't understand why file.info( ) returned such
> message. I have multiple files in this directory "E:/home work/Rstudio",
> but R shows:
> file.info("E:/home work/Rstudio")
>                                          size isdir mode
> mtime               ctime               atime exe
> E:/home work/Rstudio    0  TRUE  777 2013-01-13 22:12:58 2013-01-13
> 20:57:36 2013-01-13 22:12:58  no
>
>  Any help ?
>
> On Mon, Jan 14, 2013 at 11:44 AM, William Dunlap <wdunlap@tibco.com>wrote:
>
>> You can use file.info("myFile") to make sure the file exists and has
>> appropriate permissions ("mode"
>> in file.info's lingo, as in Unix).  E.g.,
>>
>> > file.info("c:/temp/BO.jpeg") # this one does not exist
>>                 size isdir mode mtime ctime atime  exe
>> c:/temp/BO.jpeg   NA    NA <NA>  <NA>  <NA>  <NA> <NA>
>> > file.info("c:/temp/BO.jpg") # this one exists
>>                  size isdir mode               mtime               ctime
>>               atime
>> c:/temp/BO.jpg 150536 FALSE  666 2013-01-14 08:35:32 2013-01-14 08:33:09
>> 2013-01-14 08:33:09
>>                exe
>> c:/temp/BO.jpg  no
>>
>> I can readJPEG() the file with mode 666, but not all permission
>> information is encoded in the mode.
>>
>> Bill Dunlap
>> Spotfire, TIBCO Software
>> wdunlap tibco.com
>>
>> > -----Original Message-----
>> > From: r-help-bounces@r-project.org [mailto:r-help-bounces@r-project.org]
>> On Behalf
>> > Of Jeff Newmiller
>> > Sent: Monday, January 14, 2013 8:25 AM
>> > To: Yi Yuan; r-help@r-project.org
>> > Subject: Re: [R] readJPEG function cannot open jpeg files
>> >
>> > Being unable to open a file is a related to your operating system and
>> how R interacts with
>> > that OS. If your interactive development environment (IDE, of which
>> RStudio is an
>> > example) is trying to make things simpler for you but you don't
>> understand how to use it,
>> > then you need to ask help from your RStudio support resources, not here.
>> >
>> > When posting here, you should mention your results from using base R
>> functions like
>> >
>> > ?sessionInfo
>> > ?getwd
>> > ?list.files
>> >
>> > as indicated in the Posting Guide mentioned at the bottom of every
>> R-help email.
>> >
>> > Consistent with the fact that this is an interface issue between R and
>> the OS, sometimes
>> > you will have to investigate the problem from outside R. For example,
>> you might need to
>> > investigate issues with security permissions that are OS specific and
>> completely outside
>> > the scope of this forum.
>> >
>> ---------------------------------------------------------------------------
>> > Jeff Newmiller                        The     .....       .....  Go
>> Live...
>> > DCN:<jdnewmil@dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
>> Go...
>> >                                       Live:   OO#.. Dead: OO#..  Playing
>> > Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
>> > /Software/Embedded Controllers)               .OO#.       .OO#.
>>  rocks...1k
>> >
>> ---------------------------------------------------------------------------
>> > Sent from my phone. Please excuse my brevity.
>> >
>> > Yi Yuan <lambandme@gmail.com> wrote:
>> >
>> > >I installed jpeg package and tried to use
>> > >
>> > >kim<-readJPEG("kim.jpeg") to read in a jpeg file, but R gave me an
>> > >error:
>> > >Error in readJPEG("kim.jpeg") : unable to open kim.jpeg
>> > >
>> > >I already put "kim.jpeg" in Rstudio's default working directory:
>> > >"E:\home
>> > >work\Rstudio". So I don't think it's a problem caused by omitting the
>> > >file's
>> > >path. But I tried with the full path version just in case and still got
>> > >the
>> > >"unable to open" error:
>> > >
>> > >kim<-readJPEG("E:\\ home work\\Rstudio\\kim.jpeg")
>> > >Error in readJPEG("E:\\ home work\\Rstudio\\kim.jpeg") :
>> > >  unable to open E:\ home work\Rstudio\kim.jpeg
>> > >
>> > >So now I really don't know what is wrong.
>> > >
>> > >     [[alternative HTML version deleted]]
>> > >
>> > >______________________________________________
>> > >R-help@r-project.org mailing list
>> > >https://stat.ethz.ch/mailman/listinfo/r-help
>> > >PLEASE do read the posting guide
>> > >http://www.R-project.org/posting-guide.html
>> > >and provide commented, minimal, self-contained, reproducible code.
>> >
>> > ______________________________________________
>> > R-help@r-project.org mailing list
>> > https://stat.ethz.ch/mailman/listinfo/r-help
>> > PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> > and provide commented, minimal, self-contained, reproducible code.
>>
>
>

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