NOTE: after reading this post head on over to this new one as it has wrapped this functionality (and more!) into a package.
Also: docxtractr is now on CRAN
This was asked on twitter recently:
The answer is a very cautious “yes”. Much depends on how well-formed and un-formatted the table is.
Take this really simple docx file: data.docx.
It has a single table in it:
Now, .docx files are just zipped directories, so rename that to data.zip, unzip it and navigate to data/word/document.xml and you’ll see something like this (though it’ll be more compressed):
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<w:document xmlns:wpc="http://schemas.microsoft.com/office/word/2010/wordprocessingCanvas" xmlns:mo="http://schemas.microsoft.com/office/mac/office/2008/main" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:mv="urn:schemas-microsoft-com:mac:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" xmlns:m="http://schemas.openxmlformats.org/officeDocument/2006/math" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:wp14="http://schemas.microsoft.com/office/word/2010/wordprocessingDrawing" xmlns:wp="http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawing" xmlns:w10="urn:schemas-microsoft-com:office:word" xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main" xmlns:w14="http://schemas.microsoft.com/office/word/2010/wordml" xmlns:w15="http://schemas.microsoft.com/office/word/2012/wordml" xmlns:wpg="http://schemas.microsoft.com/office/word/2010/wordprocessingGroup" xmlns:wpi="http://schemas.microsoft.com/office/word/2010/wordprocessingInk" xmlns:wne="http://schemas.microsoft.com/office/word/2006/wordml" xmlns:wps="http://schemas.microsoft.com/office/word/2010/wordprocessingShape" mc:Ignorable="w14 w15 wp14">
<w:body>
<w:tbl>
<w:tblPr>
<w:tblStyle w:val="TableGrid"/>
<w:tblW w:w="0" w:type="auto"/>
<w:tblLook w:val="04A0" w:firstRow="1" w:lastRow="0" w:firstColumn="1" w:lastColumn="0" w:noHBand="0" w:noVBand="1"/>
</w:tblPr>
<w:tblGrid>
<w:gridCol w:w="2337"/>
<w:gridCol w:w="2337"/>
<w:gridCol w:w="2338"/>
<w:gridCol w:w="2338"/>
</w:tblGrid>
<w:tr w:rsidR="00244D8A" w14:paraId="6808A6FE" w14:textId="77777777" w:rsidTr="00244D8A">
<w:tc>
<w:tcPr>
<w:tcW w:w="2337" w:type="dxa"/>
</w:tcPr>
<w:p w14:paraId="7D006905" w14:textId="77777777" w:rsidR="00244D8A" w:rsidRDefault="00244D8A">
<w:r>
<w:t>This</w:t>
</w:r>
</w:p>
</w:tc>
<w:tc>
<w:tcPr>
<w:tcW w:w="2337" w:type="dxa"/>
</w:tcPr>
<w:p w14:paraId="13C9E52C" w14:textId="77777777" w:rsidR="00244D8A" w:rsidRDefault="00244D8A">
<w:r>
<w:t>Is</w:t>
</w:r>
</w:p>
</w:tc>
...
We can easily make out a table structure with rows and columns. In the simplest cases (which is all I’ll cover in this post) where the rows and columns are uniform it’s pretty easy to grab the data:
library(xml2)
# read in the XML file
doc <- read_xml("data/word/document.xml")
# there is an egregious use of namespaces in these files
ns <- xml_ns(doc)
# extract all the table cells (this is assuming one table in the document)
cells <- xml_find_all(doc, ".//w:tbl/w:tr/w:tc", ns=ns)
# convert the cells to a matrix then to a data.frame)
dat <- data.frame(matrix(xml_text(cells), ncol=4, byrow=TRUE),
stringsAsFactors=FALSE)
# if there are column headers, make them the column name and remove that line
colnames(dat) <- dat[1,]
dat <- dat[-1,]
rownames(dat) <- NULL
dat
## This Is A Column
## 1 1 Cat 3.4 Dog
## 2 3 Fish 100.3 Bird
## 3 5 Pelican -99 Kangaroo
You’ll need to clean up the column types, but you have at least freed the data from the evil file format it was in.
If there is more than one table you can use XML node targeting to process each one separately or into a list. I’ve wrapped that functionality into a rudimentary function that will:
- auto-copy a Word doc to a temporary location
- rename it to a zip
- unzip it to a temporary location
- read in the
document.xml
- auto-determine the number of tables in the document
- auto-calculate # rows & # columns per table
- convert each table
- return all the tables into a list
- clean up the temporarily created items
library(xml2)
get_tbls <- function(word_doc) {
tmpd <- tempdir()
tmpf <- tempfile(tmpdir=tmpd, fileext=".zip")
file.copy(word_doc, tmpf)
unzip(tmpf, exdir=sprintf("%s/docdata", tmpd))
doc <- read_xml(sprintf("%s/docdata/word/document.xml", tmpd))
unlink(tmpf)
unlink(sprintf("%s/docdata", tmpd), recursive=TRUE)
ns <- xml_ns(doc)
tbls <- xml_find_all(doc, ".//w:tbl", ns=ns)
lapply(tbls, function(tbl) {
cells <- xml_find_all(tbl, "./w:tr/w:tc", ns=ns)
rows <- xml_find_all(tbl, "./w:tr", ns=ns)
dat <- data.frame(matrix(xml_text(cells),
ncol=(length(cells)/length(rows)),
byrow=TRUE),
stringsAsFactors=FALSE)
colnames(dat) <- dat[1,]
dat <- dat[-1,]
rownames(dat) <- NULL
dat
})
}
Using this multi-table Word doc – doc3:
we can extract the three tables thusly:
get_tbls("~/Dropbox/data3.docx")
## [[1]]
## This Is A Column
## 1 1 Cat 3.4 Dog
## 2 3 Fish 100.3 Bird
## 3 5 Pelican -99 Kangaroo
##
## [[2]]
## Foo Bar Baz
## 1 Aa Bb Cc
## 2 Dd Ee Ff
## 3 Gg Hh ii
##
## [[3]]
## Foo Bar
## 1 Aa Bb
## 2 Dd Ee
## 3 Gg Hh
## 4 1 2
## 5 Zz Jj
## 6 Tt ii
This function tries to calculate the rows/columns per table but it does rely on a uniform table structure.
Have an alternate method or more feature-complete way of handling Word docs as tabular data sources? Then definitely drop a note in the comments.
