Rcpp: Trouble with linking to Shogun C++ files

Question

I am writing an R package and I am trying to include some of the functionality of the Shogun toolbox for machine learning . I first included the shogun folder which contains the C++ functions in the /inst/include/ folder. I then added the following statements to my Makevars and Makevars.win files:

PKG_CPPFLAGS =  -I../inst/include/

I then tried a test so in a file called test.cpp which I placed in /src , and which includes the following:

#include <shogun/lib/config.h>

and I get the error: test.cpp: fatal error: shogun/lib/config.h: No such file or directory compilation terminated.

What am I doing wrong?

Answer 1

You are trying to create a header only package out of a library that is not header only.

That is to say in the /inst/include/ you have a mixture of .h and .cpp . To rectify this, you should only retain the .h files in /inst/include/ . Keep a copy of the .h and .cpp together files in /src .

The best package to model your package after is RcppMLPACK1 with its use of inst/include/ , src/ , plugin manager definition , and linking plus cxx flags .

However, you might just want to create a package that links to system's libraries. eg RcppMLPACK2 . This package uses configure.ac , which is the master autoconf to generate configure to ensure the necessary paths are present. Note of extensions to autoconf in the m4 directory