anchor.diff:  # install nbresuse to show users memory usage
   RUN pip install git+https://github.com/data-8/nbresuse.git@2f9144f
   RUN jupyter serverextension enable  --sys-prefix --py nbresuse && \
  -	jupyter nbextension     install --sys-prefix --py nbresuse && \
  -	jupyter nbextension     enable  --sys-prefix --py nbresuse
  +    jupyter nbextension     install --sys-prefix --py nbresuse && \
  +    jupyter nbextension     enable  --sys-prefix --py nbresuse
   
   # install nbgitpuller
   RUN jupyter serverextension enable  --sys-prefix --py nbgitpuller
  
positive.code: RUN apt-get install --yes neurodebian
  RUN apt-get update && apt-get install --yes fsl-complete
  
  # install R
  RUN apt-get install --yes \
              libgdal-dev \
              libproj-dev \
              r-base \
              r-base-dev \
              r-cran-base64enc \
              r-cran-broom \
              r-cran-crayon \
              r-cran-curl \
              r-cran-devtools \
              r-cran-digest \
              r-cran-dplyr \
              r-cran-evaluate \
              r-cran-ggplot2 \
              r-cran-htmlwidgets \
              r-cran-httr \
              r-cran-mapproj \
              r-cran-maptools \
  
negative.code: 
  # github ref is version 1.3-2
  RUN Rscript -e "devtools::install_github('cran/rgdal', ref = '8ae242d', upgrade_dependencies = FALSE)"
  
  ENV RSTUDIO_URL https://download2.rstudio.org/rstudio-server-1.1.453-amd64.deb
  ENV RSTUDIO_CHECKSUM 3c546fa9067f48ed1a342f810fca8be6
  
  # install rstudio
  RUN curl --silent --location --fail ${RSTUDIO_URL} > /tmp/rstudio.deb && \
      echo "${RSTUDIO_CHECKSUM} /tmp/rstudio.deb" | md5sum -c - && \
      dpkg -i /tmp/rstudio.deb && \
      rm /tmp/rstudio.deb
  
  RUN echo 'PATH=${PATH}:/usr/lib/rstudio-server/bin' > \
  	/etc/profile.d/site-rstudio.sh
  
  RUN apt-get purge && apt-get clean
  
  