[R] readPDF() -- unsure how to install xpdf to make this work?

Sun Nov 16 21:40:52 CET 2008

Hi Uwe, that is what i have now done, following the sugestion from
Joris, but unfortuantly that hasn't worked.

Cheers,
Tony Breyal

Ps. i would like to appologise, i am replying to these posts through
google.groups.co.uk and there is a delay beween me posting a reply and
that post appearing in the thread.

On 16 Nov, 20:34, Uwe Ligges <lig... at statistik.tu-dortmund.de> wrote:
> Tony Breyal wrote:
> > Hi,
>
> > Uwe -- ahh, thank you kindly, I was able to do a web search after
> > reading your post above in order to find a guide on how to set the
> > path in windows (i wasn't aware that this is how a file is made
> > avaiable to the system). I haven't got it to work yet, but at least
> > i'm on the right track! also just after reading your post, i've
> > discoverd the system() function in R, what wonderful thing that is!
>
> > Clair -- I'm still working on getting the files to be accessable to
> > the system, but in the mean time i have just discovered the system()
> > function in R which is work around for the moment... so using your
> > example, you could do:
> > ## R code
> >> system(paste('"C:/Program Files/xpdf/pdftotext.exe"', '"C:/Documents and Settings/clair/Desktop/test/r-intro.pdf"'), wait=FALSE)
>
> > the above will create a new text document in your c:/../test folder.
>
> > Now obviously, we want to use the readPDF() function in package: tm.
> > so on my uni laptop, running windows XP, this is what i have done:
>
> > 1. Click through: start >> control panel >> system
> > 2. Click the Advanced tab.
> > 3. Click Environment variables.
> > 4. Click New (under 'system') to add a new variable name and value.
> >   4a. name: pdftotext
> >   4b. value: C:\Program Files\xpdf\pdftotext.exe
> > 5. Click New (under 'system') to add a new variable name and value.
> >   4a. name: pdfinfo
> >   4b. value: C:\Program Files\xpdf\pdfinfo.exe
>
> No, instead of 4 and 5, change the environemnt variable PATH to
>
> PATH
> ...[all what is already in there]...;C:\Program Files\xpdf
>
> Uwe Ligges
>
>
>
> > In theory, i think, that should work. however so far it hasn't, so not
> > quite sure what to do. but at least in the mean time we have the system
> > () function as a work around. If you can figure out what i'm doing
> > wrong (probably something obvious knowing me!) please do let me know.
>
> > Cheers,
> > Tony Breyal
>
> > On 16 Nov, 18:14, Uwe Ligges <lig... at statistik.tu-dortmund.de> wrote:
> >> clair.crossup... at googlemail.com wrote:
> >>> I never said it *should* work.
> >>> I was simply trying something out that works on other types of files
> >>> I've needed in the past (eg: html, csv, dat, etc.). I don't know the
> >>> details of the pdf format, but I thought it was worth a try, certainly
> >>> no harm in experimenting, and hence I learned that pdfs aren't stored
> >>> in the same way that other files i've used in the past are. that's
> >>> fine, good to learn new things.
> >>> As for trying the readPDF() function, yes, I have downloaded and used
> >>> xpdf to convert pdfs into plain text since reading the OP email.
> >>> However, ow you can make xpdf available to the system so that readPDF
> >>> () works in R? i don't know, hence why I posted in this thread.
> >>> You clearly seem to have a solution, fancy sharing?
> >> Sure, I thought that could not be a real question:
> >> Set your environment variable PATH so that it additionally points to the
> >> directory where these tools are installed. As you would do for any other
> >> software that is to be called without knowledge where it is installed.
>
> >> Uwe Ligges
>
> >>> Clair Crossupton xx
> >>> On 16 Nov, 12:34, Uwe Ligges <lig... at statistik.tu-dortmund.de> wrote:
> >>>> clair.crossup... at googlemail.com wrote:
> >>>>> Hello, I was just wondering if you had found a solution? I am having
> >>>>> the same difficulty of converting pdf's into plain text documents in
> >>>>> R. I originally thought I could use the readLines() function, but as
> >>>>> you can see below that did not work.
> >>>> Why the hell should it? It is designed to read *text* files. And what
> >>>> you get below is exactly how your PDF file looks like if you read it as
> >>>> text which it is NOT. Why do you not also go the readPDF() way (and yes,
> >>>> it is not always possible nor reliable to go that way).
> >>>> Uwe Ligges
> >>>>> R> my.destfile <- "C:\\Documents and Settings\\clair\\Desktop\\test\\r-
> >>>>> intro.pdf"
> >>>>> R> my.url <- "http://cran.r-project.org/doc/manuals/R-intro.pdf"
> >>>>> R> download.file(url = my.url, destfile=my.destfile, mode='wb')
> >>>>> R> txt <- readLines(my.destfile)
> >>>>> R> txt
> >>>>> [1]
> >>>>> "%PDF-1.4"
> >>>>> [2]
> >>>>> "%ÐÔÅØ"
> >>>>> [3] "1 0 obj
> >>>>> <<"
> >>>>> [4] "/Length 587
> >>>>> "
> >>>>> [5] "/Filter /
> >>>>> FlateDecode"
> >>>>> [6]
> >>>>> ">>"
> >>>>> [7]
> >>>>> "stream"
> >>>>> [8] "xÚmTM ¢@\020½ó+z\017&ÎÁ±?\024tBL\020$ñ°ãd4›½*´.‰\002\001<øï·_•èÌf
> >>>>> \017’W¯_wÕ«îrðãc;Šòê`GæUŠOÛV×&³£øç¾ö\006ƒ¤Ê®\027[vïÖæ6ïWÛ7ñÑTÙÖvb
> >>>>> \030¯“uYt/N¼.³ó5·½êÿ¢¥=\025åS‚<b¸³¿G› "
> >>>>> Warm Regards,
> >>>>> Clair
> >>>>> On 13 Nov, 15:10, Tony Breyal <tony.bre... at googlemail.com> wrote:
> >>>>>> Dear R-Help,
> >>>>>> I need to convert a set of '.pdf' files into an equivalent set of
> >>>>>> '.txt' files. This is so that i can do some text mining on the
> >>>>>> content.
> >>>>>> In the latest R-News letter (http://cran.r-project.org/doc/Rnews/
> >>>>>> Rnews_2008-2.pdf), the package 'tm' for text mining is mentioned. In
> >>>>>> that lovely package, there is a function called 'readPDF()'. In order
> >>>>>> to use this, ?readPDF says
> >>>>>>     "Note that this PDF reader needs both the tools pdftotext and
> >>>>>> pdfinfo installed and accessable on your system."
> >>>>>> These tools are available fromhttp://www.foolabs.com/xpdf/download.html
> >>>>>> I am able to download this and use it easily from a dos window to
> >>>>>> convert a pdf file into a txt file.
> >>>>>> Question: how do i make these tools available to R, so that i can use
> >>>>>> the readPDF() function?
> >>>>>> Thank you in advance for any help, and I hope the above made sense.
> >>>>>> Tony Breyal
> >>>>>> ###OS = Windows Vista Ultimate>> sessionInfo()
> >>>>>> R version 2.8.0 (2008-10-20)
> >>>>>> i386-pc-mingw32
> >>>>>> locale:
> >>>>>> LC_COLLATE=English_United Kingdom.1252;LC_CTYPE=English_United Kingdom.
> >>>>>> 1252;LC_MONETARY=English_United Kingdom.
> >>>>>> 1252;LC_NUMERIC=C;LC_TIME=English_United Kingdom.1252
> >>>>>> attached base packages:
> >>>>>> [1] grid      stats     graphics  grDevices utils     datasets
> >>>>>> methods   base
> >>>>>> other attached packages:
> >>>>>> [1] tm_0.3-1           XML_1.98-1         Snowball_0.0-3
> >>>>>> RWeka_0.3-14       rJava_0.6-0        Matrix_0.999375-16
> >>>>>> lattice_0.17-15    filehash_2.0
> >>>>>> loaded via a namespace (and not attached):
> >>>>>> [1] proxy_0.4-1
> >>>>>> ______________________________________________
> >>>>>> R-h... at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> >>>>>> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> >>>>>> and provide commented, minimal, self-contained, reproducible code.
> >>>>> ------------------------------------------------------------------------
> >>>>> ______________________________________________
> >>>>> R-h... at r-project.org mailing list
> >>>>>https://stat.ethz.ch/mailman/listinfo/r-help
> >>>>> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> >>>>> and provide commented, minimal, self-contained, reproducible code.
> >>>> ______________________________________________
> >>>> R-h... at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> >>>> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> >>>> and provide commented, minimal, self-contained, reproducible code.
> >>> ______________________________________________
> >>> R-h... at r-project.org mailing list
> >>>https://stat.ethz.ch/mailman/listinfo/r-help
> >>> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> >>> and provide commented, minimal, self-contained, reproducible code.
> >> ______________________________________________
> >> R-h... at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> >> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> >> and provide commented, minimal, self-contained, reproducible code.
>
> > ______________________________________________
> > R-h... at r-project.org mailing list
> >https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-h... at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.