anchor.diff:  
   # update the R packages we will need for knitr
   RUN DEBIAN_FRONTEND=noninteractive wget \
  -   https://archive.linux.duke.edu/cran/src/contrib/knitr_1.16.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/yaml_2.1.14.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/Rcpp_0.12.11.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/htmltools_0.3.6.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/caTools_1.17.1.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/bitops_1.0-6.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/digest_0.6.12.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/stringr_1.2.0.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/markdown_0.8.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/highr_0.6.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/formatR_1.5.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/evaluate_0.10.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/mime_0.5.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/stringi_1.1.5.tar.gz \
  -   https://archive.linux.duke.edu/cran/src/contrib/magrittr_1.5.tar.gz
  +   https://mirrors.nics.utk.edu/cran/src/contrib/knitr_1.16.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/yaml_2.1.14.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/Rcpp_0.12.11.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/htmltools_0.3.6.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/caTools_1.17.1.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/bitops_1.0-6.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/digest_0.6.12.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/stringr_1.2.0.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/markdown_0.8.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/highr_0.6.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/formatR_1.5.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/evaluate_0.10.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/mime_0.5.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/stringi_1.1.5.tar.gz \
  +   https://mirrors.nics.utk.edu/cran/src/contrib/magrittr_1.5.tar.gz
   
   
   RUN DEBIAN_FRONTEND=noninteractive R CMD INSTALL \
  
positive.code: 
  # Cliburn Chan requested these:
  RUN DEBIAN_FRONTEND=noninteractive wget \
     https://archive.linux.duke.edu/cran/src/contrib/RColorBrewer_1.1-2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/maps_3.2.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/zoo_1.8-0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/gcookbook_1.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/corrplot_0.77.tar.gz 
  
  
  RUN DEBIAN_FRONTEND=noninteractive R CMD INSTALL \
  
negative.code: 
  # install templates and examples from Reed and the Tufte package
  RUN DEBIAN_FRONTEND=noninteractive wget \
     https://mirrors.nics.utk.edu/cran/src/contrib/BHH2_2016.05.31.tar.gz
     
  RUN DEBIAN_FRONTEND=noninteractive R CMD INSTALL \
     BHH2_2016.05.31.tar.gz
  