anchor.diff:  # install conda
   ENV PATH /conda/bin:$PATH
   RUN echo 'export PATH=/conda/bin:$PATH' > /etc/profile.d/conda.sh && \
  -    curl https://repo.continuum.io/miniconda/Miniconda2-latest-Linux-x86_64.sh \
  +    curl https://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh \
           -o ~/miniconda.sh && \
       /bin/bash ~/miniconda.sh -b -p /conda && \
       rm ~/miniconda.sh
  
positive.code: 
  # install cdf, spacepy, and magpy
  RUN cd /tmp && \ 
      wget http://cdaweb.gsfc.nasa.gov/pub/software/cdf/dist/cdf36_4/linux/cdf36_4-dist-all.tar.gz && \
      tar zxvf cdf36_4-dist-all.tar.gz && \
      cd cdf36* && \
      make OS=linux ENV=gnu CURSES=yes FORTRAN=no UCOPTIONS=-O2 SHARED=yes all && \
      make INSTALLDIR=/usr/local/cdf install && \
      cd /tmp && \
      pip install spacepy && \
      pip install geomagpy && \
      cd /tmp && \
      rm -rf /tmp/cdf36*
  
  
  USER magpy_user
  
negative.code: 
  # install obspy and dependencies via conda
  RUN conda config --add channels obspy && \
      conda install --yes jupyter obspy matplotlib && \
      conda clean -i -l -t -y && \
      useradd \
          -c 'Docker image user' \
  