fulltext (version 0.1.8)

ft_extract: Extract text from a single pdf document

Description

ft_extract attemps to make it easy to extract text from PDFs, using a variety of extraction tools. Inputs can be either paths to PDF files, or the output of ft_get (class ft_data).

Usage

ft_extract(x, which = "xpdf", ...)
# S3 method for gs_char
print(x, ...)
# S3 method for xpdf_char
print(x, ...)

Arguments

x

Path to a pdf file, or an object of class ft_data, the output from ft_get

which

One of gs or xpdf (default).

...

further args passed on

Value

An object of class gs_char, xpdf_char

Details

For xpdf, you can pass on addition options via flags. See Examples. Right now, you can't pass options to Ghostscript if you're using the gs option.

xpdf installation: See http://www.foolabs.com/xpdf/download.html for instructions on how to download and install xpdf. For OSX, you an also get xpdf via homebrew.

ghostscript installation: See http://www.ghostscript.com/doc/9.16/Install.htm for instructions on how to download and install ghostscript

Examples

# NOT RUN {
path <- system.file("examples", "example1.pdf", package = "fulltext")

(res_xpdf <- ft_extract(path)) # xpdf is the default
(res_xpdf <- ft_extract(path, "xpdf"))
(res_gs <- ft_extract(path, "gs"))

# pass on options to xpdf
## preserve layout from pdf
ft_extract(path, "xpdf", "-layout")
## preserve table structure as much as possible
ft_extract(path, "xpdf", "-table")
## last page to convert is page 2
ft_extract(path, "xpdf", "-l 2")
## first page to convert is page 3
ft_extract(path, "xpdf", "-f 3")

# use on output of ft_get() to extract pdf to text
## arxiv
res <- ft_get('cond-mat/9309029', from = "arxiv")
res2 <- ft_extract(res)
res$arxiv$data
res2$arxiv$data
res2$arxiv$data$data[[1]]$data

## biorxiv
res <- ft_get('10.1101/012476')
res2 <- ft_extract(res)
res$biorxiv$data
res2$biorxiv$data
res2$biorxiv$data$data[[1]]$data
# }