windkit.shear_exponent#
- windkit.shear_exponent(da)[source]#
Compute the shear exponent from vertical wind speed profiles using finite differences in log-space.
- Parameters:
da (xarray.DataArray) – Wind speed DataArray. The DataArray must contain a height coordinate and horizontal coordinates (‘west_east’, ‘south_north’) or be convertible to that structure. Wind speeds must be positive.
- Returns:
The shear exponent computed as (d ln u) / (d ln z) at log-space midpoints between input heights. The returned DataArray has the same spatial structure as the input and only contains the points where valid shear calculations could be made.
- Return type:
- Raises:
ValueError – If the input cannot be converted to a point/vertical structure by windkit.spatial.to_point.
Notes
The function sorts profiles by (west_east, south_north, height) and computes backward finite differences along the “point” axis.
Midpoint heights are computed in log-space and assigned to the output shear DataArray.
Examples
>>> shear = shear_exponent(da)