Test environments

local Windows 10 install, R 3.5.1
ubuntu 14.04.5 (on travis-ci), R 3.5.1
win-builder (devel)
Rhub
- Windows Server 2008 R2 SP1, R-devel, 32/64 bit
- Ubuntu Linux 16.04 LTS, R-release, GCC
- Fedora Linux, R-devel, clang, gfortran

R CMD check results

There were no ERRORs or WARNINGs or Note.