title: how to install geoviews in python?
body: <p>i was trying to install geoviews using pip but got errors.</p>
  
  <pre><code>C:\Users\jainil&gt;pip install geoviews==1.6.2
  Collecting geoviews==1.6.2
    Using cached https://files.pythonhosted.org/packages/5d/76/7aa62a5dfdec25ab9f921223bd26507bb603bc5f08a4a7057d3f5e24f42b/geoviews-1.6.2-py2.py3-none-any.whl
  Requirement already satisfied: numpy&gt;=1.0 in c:\users\jainil\anaconda3\lib\site-packages (from geoviews==1.6.2) (1.16.4)
  Requirement already satisfied: holoviews&gt;=1.11.1 in c:\users\jainil\anaconda3\lib\site-packages (from geoviews==1.6.2) (1.12.3)
  Requirement already satisfied: bokeh&gt;=1.0.0 in c:\users\jainil\anaconda3\lib\site-packages (from geoviews==1.6.2) (1.2.0)
  Collecting cartopy&gt;=0.16.0 (from geoviews==1.6.2)
    Using cached https://files.pythonhosted.org/packages/e5/92/fe8838fa8158931906dfc4f16c5c1436b3dd2daf83592645b179581403ad/Cartopy-0.17.0.tar.gz
    Installing build dependencies ... done
    Getting requirements to build wheel ... error
    ERROR: Complete output from command 'C:\Users\jainil\Anaconda3\python.exe' 'C:\Users\jainil\Anaconda3\lib\site-packages\pip\_vendor\pep517\_in_process.py' get_requires_for_build_wheel 'C:\Users\jainil\AppData\Local\Temp\tmp25d9ovmd':
    ERROR: setup.py:171: UserWarning: Unable to determine GEOS version. Ensure you have 3.3.3 or later installed, or installation may fail.
      '.'.join(str(v) for v in GEOS_MIN_VERSION), ))
    Proj 4.9.0 must be installed.
    ----------------------------------------
  ERROR: Command "'C:\Users\jainil\Anaconda3\python.exe' 'C:\Users\jainil\Anaconda3\lib\site-packages\pip\_vendor\pep517\_in_process.py' get_requires_for_build_wheel 'C:\Users\jainil\AppData\Local\Temp\tmp25d9ovmd'" failed with error code 1 in C:\Users\jainil\AppData\Local\Temp\pip-install-sjcurctz\cartopy
  </code></pre>
  
  <p>ok it is solved.</p>