title: After installing rpy2 the library for R is pointing to miniconda
body: <p>I was trying to use <code>rpy2</code> to interoperate <code>R</code> and <code>python</code> in <code>jupyter</code>. It was just a curiosity experiment.  It is not working due to package imports.</p>
  <p>But what is <em>not</em> an experiment is to be able to install packages in <code>R</code> . I can no longer do so after installing <code>rpy2</code>.  The following is happening in <code>R</code>:</p>
  <pre><code>&gt; install.packages('ggplot2')
  
   .. various errors including 
  
  In file included from /Users/steve/miniconda3/lib/R/include/R.h:50:
  /Users/steve/miniconda3/bin/../include/c++/v1/cmath:317:9: error: no member named 'signbit' in the global namespace
  </code></pre>
  <p>Why is <code>miniconda3</code> in the picture <em>at all</em> here?</p>
  <p>Later we see:</p>
  <pre><code>ERROR: compilation failed for package ‘isoband’
  * removing ‘/Users/steve/miniconda3/lib/R/library/isoband’
  ERROR: dependency ‘isoband’ is not available for package ‘
  </code></pre>
  <p>Why is the <code>R</code> library directory now pointed to <code>miniconda3</code> ?   How do I get back to the normal R libraries location?</p>