xarray.Variable.rolling_window

xarray.Variable.rolling_window#

Variable.rolling_window(dim, window, window_dim, *, center=False, fill_value=<NA>, **kwargs)[source]#

Make a rolling_window along dim and add a new_dim to the last place.

Parameters:

  • dim (str) – Dimension over which to compute rolling_window. For nd-rolling, should be list of dimensions.

  • window (int) – Window size of the rolling For nd-rolling, should be list of integers.

  • window_dim (str) – New name of the window dimension. For nd-rolling, should be list of strings.

  • center (bool, default: False) – If True, pad fill_value for both ends. Otherwise, pad in the head of the axis.

  • fill_value – value to be filled.

  • **kwargs – Keyword arguments that should be passed to the underlying array type’s sliding_window_view function.

Returns:

  • Variable that is a view of the original array with a added dimension of

  • size w.

  • The return dim (self.dims + (window_dim, ))

  • The return shape (self.shape + (window, ))

See also

numpy.lib.stride_tricks.sliding_window_view, dask.array.lib.stride_tricks.sliding_window_view

Examples

>>> v = Variable(("a", "b"), np.arange(8).reshape((2, 4)))
>>> v.rolling_window("b", 3, "window_dim")
<xarray.Variable (a: 2, b: 4, window_dim: 3)> Size: 192B
array([[[nan, nan,  0.],
        [nan,  0.,  1.],
        [ 0.,  1.,  2.],
        [ 1.,  2.,  3.]],

       [[nan, nan,  4.],
        [nan,  4.,  5.],
        [ 4.,  5.,  6.],
        [ 5.,  6.,  7.]]])

>>> v.rolling_window("b", 3, "window_dim", center=True)
<xarray.Variable (a: 2, b: 4, window_dim: 3)> Size: 192B
array([[[nan,  0.,  1.],
        [ 0.,  1.,  2.],
        [ 1.,  2.,  3.],
        [ 2.,  3., nan]],

       [[nan,  4.,  5.],
        [ 4.,  5.,  6.],
        [ 5.,  6.,  7.],
        [ 6.,  7., nan]]])