rJAVA Rstudio bug

https://github.com/rstudio/rstudio/issues/2254

set root.dir in knitr

https://philmikejones.wordpress.com/2015/05/20/set-root-directory-knitr/

library(xlsx) rJava problem in Rstudio

follow instrucitons on:
http://stackoverflow.com/questions/30738974/rjava-load-error-in-rstudio-r-after-upgrading-to-osx-yosemite

 sudo ln -s $(/usr/libexec/java_home)/jre/lib/server/libjvm.dylib /usr/local/lib/.

RStudio workspace size problem, LDKEY is too small for this problem. FEXACT error 6.

This seems to be error to show that Exact test is unnecessary, based on
http://www.datavis.ca/courses/VCD/vcd-tutorial.pdf