===============
Hodograph Inset
===============
`Notebook <http://nbviewer.ipython.org/github/metpy/MetPy/blob/master/examples/notebooks/Hodograph_Inset.ipynb>`_

.. code:: ipython3

    import numpy as np
    import matplotlib.pyplot as plt
    from mpl_toolkits.axes_grid1.inset_locator import inset_axes
    
    from metpy.cbook import get_test_data
    from metpy.calc import get_wind_components
    from metpy.plots import SkewT, Hodograph
    from metpy.units import units
    
    %matplotlib inline

.. code:: ipython3

    # Parse the data
    p, T, Td, direc, spd = np.loadtxt(get_test_data('may3_sounding.txt'),
            usecols=(0, 2, 3, 6, 7), skiprows=4, unpack=True)

.. code:: ipython3

    # Add units to the data arrays
    p = p * units.mbar
    T = T * units.degC
    Td = Td * units.degC
    spd = spd * units.knot
    direc = direc * units.deg

.. code:: ipython3

    # Convert wind speed and direction to components
    u, v = get_wind_components(spd, direc)

.. code:: ipython3

    # Create a new figure. The dimensions here give a good aspect ratio
    fig = plt.figure(figsize=(9, 9))
    
    # Grid for plots
    skew = SkewT(fig, rotation=45)
    
    # Plot the data using normal plotting functions, in this case using
    # log scaling in Y, as dictated by the typical meteorological plot
    skew.plot(p, T, 'r')
    skew.plot(p, Td, 'g')
    skew.plot_barbs(p, u, v)
    skew.ax.set_ylim(1000, 100)
    
    # Add the relevant special lines
    skew.plot_dry_adiabats()
    skew.plot_moist_adiabats()
    skew.plot_mixing_lines()
    
    # Good bounds for aspect ratio
    skew.ax.set_xlim(-50, 60)
    
    # Create a hodograph
    ax_hod = inset_axes(skew.ax, '40%', '40%', loc=1)
    h = Hodograph(ax_hod, component_range=80.)
    h.add_grid(increment=20)
    h.plot_colormapped(u, v, spd)
    
    # Show the plot
    plt.show()



.. image:: Hodograph_Inset_files/Hodograph_Inset_4_0.png