Raise warning for data points less than or equal to 5e3.

Update test to check for data points less than 5e3 and the associated warning.

harmonica/_equivalent_sources/gradient_boosted.py

@@ -14,6 +14,7 @@
 
 from .cartesian import EquivalentSources
 from .utils import cast_fit_input, predict_numba_parallel
+import warnings
 
 
 class EquivalentSourcesGB(EquivalentSources):
@@ -275,7 +276,7 @@ def _create_windows(self, coordinates, shuffle=True):
  coordinates : tuple
  Arrays with the coordinates of each data point. Should be in the
  following order: (``easting``, ``northing``, ``upward``).
- shuffle_windows : bool
+ shuffle : bool
  Enable or disable the random shuffling of windows order. It's is
  highly recommended to enable shuffling for better fitting results.
  This argument is mainly included for testing purposes. Default to
@@ -290,7 +291,7 @@ def _create_windows(self, coordinates, shuffle=True):
  the same as the one in ``data_windows_nonempty``.
  data_windows_nonempty : list
  List containing arrays with the indices of the data points that
- under each window. The order of the windows is randomly shuffled if
+ fall under each window. The order of the windows is randomly shuffled if
  ``shuffle_windows`` is True, although the order of the windows is
  the same as the one in ``source_windows_nonempty``.
  """
@@ -302,6 +303,12 @@ def _create_windows(self, coordinates, shuffle=True):
  if self.window_size == "default":
  area = (region[1] - region[0]) * (region[3] - region[2])
  ndata = coordinates[0].size
+ if ndata <= 5e3:
+ warnings.warn(f"Found {ndata} number of coordinates (<= 5e3). Only one window will be used.")
+ source_windows_nonempty = [np.arange(self.points_[0].size)]
+ data_windows_nonempty = [np.arange(ndata)]
+ self.window_size_ = None
+ return source_windows_nonempty, data_windows_nonempty
  points_per_m2 = ndata / area
  window_area = 5e3 / points_per_m2
  self.window_size_ = np.sqrt(window_area)

harmonica/tests/test_gradient_boosted_eqs.py

@@ -382,9 +382,9 @@ def test_window_size_less_than_5000():
  eqs.points_ = eqs._build_points(
  grid_coords
  ) # need to build sources first before creating windows.
- eqs._create_windows(grid_coords)
- expected_window_size = np.sqrt(5e3 / (64**2 / 10e3**2))
- npt.assert_allclose(eqs.window_size_, expected_window_size)
+ with pytest.warns(UserWarning, match=f"Found {64**2} number of coordinates"):
+  eqs._create_windows(grid_coords)
+ assert eqs.window_size_ is None
 
 def test_window_size():
  region = (0, 10e3, -5e3, 5e3)