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

Sun Nov 16 19:14:31 CET 2008

clair.crossupton 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-help at 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.