Also see the blog site for this and related material.
GNU Make is a commonly used tool as part of the process for managing software projects.
Data analysis can involve many steps including reading data; cleaning and transforming data; plotting data, statistical analysis and finally writing reports. While we can try and keep track of each step manually by using good documentation and being highly organised, it can prove to be more efficient to employ computer tools to augment these practices. One such approach is to use a tool like GNU Make. Such an approach does not obviate the need to be organised and document the work but it can certainly prove helpful, especially as a project grows in size.
While it is far from perfect, make is widely used and generally proves to be useful for efficiently carrying out tasks in data analysis. Unfortunately, make does not provide standard rules for producing .Rout files from .R files, .pdf files from .Rnw files, .docx files from .Rmd files and so on.
The file common.mk can be included in a standard Makefile to facilitate a more efficient workflow.
- Download the file to a directory you use for files. Ideally,
this would something like:
- ~/lib or C:\MyLibrary
- put the following line in your Makefile
- include ~/lib/common.mk where ~ will be expanded to be your HOME directory, or
- include C:/MyLibrary/common.mk (in windows)
Note: the very simplest way to run make would be to simply create a new text file named Makefile in your working directory with a single line above including the file common.mk. If you have an R syntax file named say mySpecialAnalysis.R then, in a terminal, you can run R to produce an output file by typing 'make mySpecialAnalysis.Rout' or produce a notebook using Rmarkdown by typing 'make mySpecialAnalysis.pdf'.
However, you will miss out on the power of make which you can harness by describing the dependencies among files.
To actually use these rules in practice, we may have several prerequisite files like an R syntax file and several data files. In the Makefile we may specify the dependencies as
readData.Rout: readData.R data1.csv data2.csv oldData.RData
so we can run the syntax file by typing ‘make readData.Rout’ at the command prompt. If any of the files readData.R, data1.csv, data2.csv or oldData.RData have changed recently, and so are newer than the target file readData.Rout, then the predefined R batch command is run to get a new output file, otherwise readData.Rout is ‘up to date’.
.PHONY : all
all: test.pdf test.html test.docx test2.pdf test-stitch.Rout test-stitch.pdf
## produce pdf, html, docx from test.Rmd
test.pdf: ${@:.pdf=.Rmd}
test.html: ${@:.html=.Rmd}
test.docx: ${@:.docx=.Rmd}
## produce pdf from test2.rmd
test2.pdf: ${@:.pdf=.rmd}
## use stitch to produce pdf via rmarkdown (exactly as in RStudio)
test-stitch.pdf: ${@:.pdf=.R}
## if you have common.mk in ~/lib directory uncomment line below and comment
include common.mk
##include ~/lib/common.mk
You can then run this with the command make or make all at the shell prompt. Any target that is not up to date will be created by running the appropriate commands. Even better: set up RStudio or your favourite editor to do this at the press of a button. Note also that because of the rules defined in common.mk, you can use make to produce targets not actually defined in the Makefile. For instance, to use stitch to create pdf output newAnalysis.pdf from the file newAnalysis.R simply type make newAnalysis.pdf at the prompt.
More usually, if there is a sequence of steps relying on a data file myData.csv your Makefile may look something like
.PHONY: all
all: report.pdf
## produce report from .Rmd once previous steps carried out
report.pdf: ${@:.pdf=.Rmd} summaryAndPlots.Rout
## summarise data
summaryAndPlots.Rout: ${@:.Rout=.R} read.Rout
## read data
read.Rout: ${@:.Rout=.R} myData.csv
include ~/lib/common.mk
To use these makefile definitions you need to install
- GNU Make http://www.gnu.org/software/make/
- R http://www.r-project.org/
- latexmk http://http://www.ctan.org/pkg/latexmk/
- R packages on CRAN: rmarkdown, knitr
Note that Windows users can install Rtools (available from CRAN) to get a working version of make and may also need to install pandoc and latex to produce pdf files if they haven't already. Miktex is recommended although texlive will also work well.
- Rtools http://cran.r-project.org/bin/windows/Rtools/
- pandoc http://johnmacfarlane.net/pandoc/
- miktex http://miktex.org/
Definitions in 'common.mk' have been developed and tested on linux and tested on windows. Some tweaking may be required.