smooth_n_point doesn't work with temperature units

[kgoebber]

So with our units work I just uncovered that having temperature units will not work with the n-point smoother due to the peculiarities of add temperatures together. See example for error.

Will work to pass non-unit arrays to smooth data, would just need to reattach units. Could work to make this happen behind the scenes pretty easily, but wanted to document here through stripping and reapplying units within the smooth_n_point function.

from metpy.calc as smooth_n_point

T = np.array([[ 2.73,  3.43,  6.53,  7.13,  4.83,  4.13,  5.53,  5.43,  4.03,  4.03,  4.83],
 [ 3.73,  4.93,  6.13,  6.63,  8.23,  6.73,  5.63,  3.13,  4.83,  5.73,  5.83],
 [ 3.03,  4.83,  6.03,  7.23,  7.63,  6.93,  6.53,  5.43,  6.53,  6.53,  6.13],
 [ 3.33,  4.63,  7.23,  6.73,  6.23,  5.43,  5.73,  7.03,  7.13,  7.53,  7.53],
 [ 3.93,  3.03,  7.43,  9.23,  9.23,  6.43,  7.93,  8.03,  7.73,  8.13,  8.33],
 [ 5.33,  5.23,  4.63,  7.03,  8.03,  7.13,  9.13,  9.83,  9.83,  9.73,  9.43],
 [ 5.23,  5.43,  5.43,  7.13,  7.43,  8.13,  8.23,  8.23,  7.93,  8.53, 11.63],
 [ 4.73,  5.23,  5.43,  5.53,  6.73,  4.93,  5.93,  7.23,  9.73,  9.23, 11.93],
 [ 4.33,  5.83,  4.03,  6.13,  6.23,  5.03,  7.43,  7.73, 10.83, 12.93, 15.43],
 [ 8.53,  6.83,  4.43,  5.33,  4.53,  5.43,  5.23,  7.03, 11.13, 14.13, 15.53],
 [ 8.53,  7.33,  8.33,  4.53,  5.03,  7.43,  8.73,  9.23, 11.43, 14.73, 16.83]]) * units.degC

smooth_T = smooth_n_point(T, 9, 1)

I don't know if this came up in previous version (don't know that I tried to smooth temperature data as I primarily have smoothed height data for contouring purposes.

[dopplershift]

Pretty sure this has likely always been broken.