=========================
Dewpoint and Mixing Ratio
=========================
`Notebook <http://nbviewer.ipython.org/github/metpy/MetPy/blob/master/examples/notebooks/Dewpoint_and_Mixing_Ratio.ipynb>`_

The goal of this notebook is to show an example using the units support
in MetPy. In this example, we calculate the dewpoint, corresponding to a
fixed value of mixing ratio, at two different surface pressure values.

.. code:: ipython3

    # First import our calculation functions, as well as unit support
    import metpy.calc as mcalc
    from metpy.units import units

.. code:: ipython3

    # Create a test value of mixing ratio in grams per kilogram
    mixing = 10 * units('g/kg')
    print(mixing)


.. parsed-literal::

    10.0 gram / kilogram


.. code:: ipython3

    # Now throw that value with units into the function to calculate
    # the corresponding vapor pressure, given a surface pressure of 1000 mb
    e = mcalc.vapor_pressure(1000. * units.mbar, mixing)
    print(e)


.. parsed-literal::

    15825.67178529092 gram * millibar / kilogram


.. code:: ipython3

    # Take the odd units and force them to millibars
    print(e.to(units.mbar))


.. parsed-literal::

    15.82567178529092 millibar


.. code:: ipython3

    # Take the raw vapor pressure and throw into the dewpoint function
    td = mcalc.dewpoint(e)
    print(td)


.. parsed-literal::

    13.856458659577921 degC


.. code:: ipython3

    # Which can of course be converted to Farenheit
    print(td.to('degF'))


.. parsed-literal::

    56.94162598724023 degF


.. code:: ipython3

    # Now do the same thing for 850 mb, approximately the pressure of Denver
    e = mcalc.vapor_pressure(850. * units.mbar, mixing)
    print(e.to(units.mbar))


.. parsed-literal::

    13.451821017497283 millibar


.. code:: ipython3

    # And print the corresponding dewpoint
    td = mcalc.dewpoint(e)
    print(td, td.to('degF'))


.. parsed-literal::

    11.378824018637602 degC 52.48188363354765 degF