AMAROC-841 raise warning if we do not filter but filter is set + adap…

…t test

src/ampycloud/data.py

@@ -13,11 +13,12 @@
 import logging
 import copy
 from abc import ABC, abstractmethod
+import warnings
 import numpy as np
 import pandas as pd
 
 # Import from this package
-from .errors import AmpycloudError
+from .errors import AmpycloudError, AmpycloudWarning
 from .logger import log_func_call
 from . import scaler, cluster, layer, fluffer
 from . import wmo, icao
@@ -536,6 +537,12 @@ def _calculate_sligrolay_base_height(
                 # of interest. Otherwise fall back to using all ceilos for the calculation.
                 if in_sligrolay_filtered.sum() > self.prms['MAX_HITS_OKTA0']:
                     in_sligrolay = in_sligrolay_filtered
+                else:
+                    warnings.warn(
+                        'Not enough data after filtering to calculate cloud base height, '
+                        f'will fall back to use all data in group/ slice/ layer {cid}',
+                        AmpycloudWarning
+                    )
             # Compute the base height
             pdf.iloc[ind, pdf.columns.get_loc('height_base')] = \
                 self._calculate_base_height_for_selection(in_sligrolay)

test/ampycloud/test_data.py

@@ -13,6 +13,7 @@
 import numpy as np
 import pandas as pd
 from pytest import raises, warns, mark, param
+import pytest
 
 # Import from the module to test
 from ampycloud.errors import AmpycloudError, AmpycloudWarning
@@ -454,7 +455,7 @@ def test_localized_base_hgt_calc_fallback():
     few hits after filtering by ceilo."""
 
     dynamic.AMPYCLOUD_PRMS['MAX_HITS_OKTA0'] = 3
-    dynamic.AMPYCLOUD_PRMS['BASE_LVL_HEIGHT_PERC'] = 50
+    dynamic.AMPYCLOUD_PRMS['BASE_LVL_HEIGHT_PERC'] = 1
     dynamic.AMPYCLOUD_PRMS['MSA'] = 10000
     dynamic.AMPYCLOUD_PRMS['MIN_SEP_VALS'] = [250, 1000]  # make sure there is only 1 layer.
 
@@ -464,9 +465,5 @@ def test_localized_base_hgt_calc_fallback():
     )
     chunk_filtered.find_slices()
     chunk_filtered.find_groups()
-    chunk_filtered.find_layers()
-
-    # Since the SD of the two layers is 2ft, it's highly unlikely that the following condition
-    # 1) is met if the filtering works (310+/-2 ft)
-    # 2) is not met if we don't go to the fallback behaviour 460 +/-2 ft)
-    assert chunk_filtered.layers.loc[0, 'height_base'] > 440.
+    with pytest.warns(AmpycloudWarning, match="will fall back to use all data"):
+        chunk_filtered.find_layers()