title: Cannot upgrade octave on Mac OSX
body: <p>I have tried updating GNU Octave through homebrew. However, I receive the following errors:</p>
  
  <pre><code>adamg:~ adamg$ brew install octave
  ==&gt; Installing octave from homebrew/science
  Error: You must `brew link gmp lua` before homebrew/science/octave can be installed
  adamg:~ adamg$ brew link gmp lua
  Linking /usr/local/Cellar/gmp/6.0.0a... 
  Error: Could not symlink include/gmpxx.h
  Target /usr/local/include/gmpxx.h
  already exists. You may want to remove it:
    rm '/usr/local/include/gmpxx.h'
  
  To force the link and overwrite all conflicting files:
    brew link --overwrite gmp
  
  To list all files that would be deleted:
    brew link --overwrite --dry-run gmp
  adamg:~ adamg$ rm '/usr/local/include/gmpxx.h'
  adamg:~ adamg$ brew link gmp lua
  Linking /usr/local/Cellar/gmp/6.0.0a... 
  Error: Could not symlink share/info/gmp.info
  Target /usr/local/share/info/gmp.info
  already exists. You may want to remove it:
    rm '/usr/local/share/info/gmp.info'
  
  To force the link and overwrite all conflicting files:
    brew link --overwrite gmp
  
  To list all files that would be deleted:
    brew link --overwrite --dry-run gmp
  </code></pre>
  
  <p>I could use octave before, but it was loading version 3.8.1. Now when I try to load it, I receive the following error</p>
  
  <pre><code>adamg:~ adamg$ octave
  dyld: Library not loaded: /usr/local/lib/libhdf5.9.dylib
    Referenced from: /usr/local/Cellar/octave/3.8.1_1/bin/octave-cli-3.8.1
    Reason: image not found
  Trace/BPT trap: 5
  </code></pre>
  
  <p>Any insight into what went wrong? I am running OSX 10.11.5.</p>