tm (version 0.3-4.1)

readPDF: Read In a PDF Document

Description

Returns a function which reads in a portable document format (PDF) document extracting both its text and its meta data.

Usage

readPDF(PdfinfoOptions = "", PdftotextOptions = "", ...)

Arguments

PdfinfoOptions

options passed over to pdfinfo.

PdftotextOptions

options passed over to pdftotext.

...

arguments for the generator function.

Value

• A function with the signature elem, language, load, id:
• elem
  A list with the two named elements content and uri. The first element must hold the document to be read in, the second element must hold a call to extract this document. The call is evaluated upon a request for load on demand.
• language
  A character vector giving the text's language.
• load
  A logical value indicating whether the document corpus should be immediately loaded into memory.
• id
  A character vector representing a unique identification string for the returned text document.
• The function returns a PlainTextDocument representing the text and meta data in content.

Details

Formally this function is a function generator, i.e., it returns a function (which reads in a text document) with a well-defined signature, but can access passed over arguments (e.g., options to pdfinfo or pdftotext) via lexical scoping.

Note that this PDF reader needs both the tools pdftotext and pdfinfo installed and accessable on your system.

See Also

Use getReaders to list available reader functions.

Examples

f <- system.file("texts", "pdf", "pdfarchiving.pdf", package = "tm")
pdf <- readPDF(PdftotextOptions = "-layout")(elem = list(uri = substitute(file(f))), load = TRUE, language = "en_US", id = "id1")
meta(pdf)