Added a dt scale factor test

Author: cgmorton

openet/ssebop/image.py

@@ -42,7 +42,6 @@ def __init__(
             et_reference_resample=None,
             et_reference_date_type=None,
             dt_source='projects/earthengine-legacy/assets/projects/usgs-ssebop/dt/daymet_median_v6',
-            # dt_scale_factor=None,
             tcorr_source='FANO',
             tmax_source='projects/earthengine-legacy/assets/projects/usgs-ssebop/tmax/daymet_v4_mean_1981_2010',
             elr_flag=False,
@@ -103,6 +102,7 @@ def __init__(
             dt_resample : {'nearest', 'bilinear'}
             tcorr_resample : {'nearest', 'bilinear'}
             tmax_resample : {'nearest', 'bilinear'}
+            dt_scale_factor : float
             elev_source : str or float
             min_pixels_per_image : int
             min_pixels_per_grid_cell : int
@@ -173,9 +173,10 @@ def __init__(
 
         # Model input parameters
         self._dt_source = dt_source
-        # self._dt_scale_factor = dt_scale_factor
         self._tcorr_source = tcorr_source
         self._tmax_source = tmax_source
+
+        # TODO: Move into keyword args section below
         self._elr_flag = elr_flag
         self._dt_min = float(dt_min)
         self._dt_max = float(dt_max)
@@ -203,6 +204,8 @@ def __init__(
         #     self.et_fraction_type = 'alfalfa'
 
         self.reflectance_type = reflectance_type
+        if reflectance_type not in ['SR', 'TOA']:
+            raise ValueError('reflectance_type must "SR" or "TOA"')
 
         # Image projection and geotransform
         self.crs = image.projection().crs()
@@ -215,21 +218,23 @@ def __init__(
         # CGM - What is the right way to process kwargs with default values?
         self.kwargs = kwargs
 
-        # CGM - Should these be checked in the methods they are used in instead?
-        # Set the resample method as properties so they can be modified
-        if 'dt_resample' in kwargs.keys():
-            self._dt_resample = kwargs['dt_resample'].lower()
+        if 'dt_scale_factor' in kwargs.keys():
+            self._dt_scale_factor = kwargs['dt_scale_factor']
         else:
-            self._dt_resample = 'bilinear'
-
-        # if 'dt_scale_factor' in kwargs.keys():
-        #     self._dt_scale_factor = kwargs['dt_scale_factor']
+            self._dt_scale_factor = None
 
         if 'elev_source' in kwargs.keys():
             self._elev_source = kwargs['elev_source']
         else:
             self._elev_source = None
 
+        # CGM - Should these be checked in the methods they are used in instead?
+        # Set the resample method as properties so they can be modified
+        if 'dt_resample' in kwargs.keys():
+            self._dt_resample = kwargs['dt_resample'].lower()
+        else:
+            self._dt_resample = 'bilinear'
+
         if 'tmax_resample' in kwargs.keys():
             self._tmax_resample = kwargs['tmax_resample'].lower()
         else:
@@ -503,6 +508,20 @@ def dt(self):
             If `self._dt_source` is not supported.
 
         """
+        if self._dt_scale_factor is None:
+            if (type(self._dt_source) is str and
+                    'projects/usgs-ssebop/dt/daymet_median_v6' in self._dt_source):
+                self._dt_scale_factor = 0.01
+            else:
+                self._dt_scale_factor = 1.0
+        elif (type(self._dt_scale_factor) is str and
+              utils.is_number(self._dt_scale_factor)):
+            self._dt_scale_factor = float(self._dt_scale_factor)
+        elif utils.is_number(self._dt_scale_factor):
+            pass
+        else:
+            raise ValueError(f'Unsupported dt_scale_factor: {self._dt_scale_factor}')
+
         if utils.is_number(self._dt_source):
             dt_img = ee.Image.constant(float(self._dt_source))
         # Use precomputed dT median assets
@@ -514,8 +533,7 @@ def dt(self):
                 .filter(ee.Filter.calendarRange(self._doy, self._doy, 'day_of_year'))
             # MF: Optional scale factor only applied for string ID dT collections, and
             #  no clamping used for string ID dT collections.
-            # dt_img = ee.Image(dt_coll.first()).multiply(self._dt_scale_factor)
-            dt_img = ee.Image(dt_coll.first()).multiply(0.01)
+            dt_img = ee.Image(dt_coll.first()).multiply(self._dt_scale_factor)
         elif self._dt_source.upper() == 'DAYMET_MEDIAN_V0':
             dt_coll = ee.ImageCollection(PROJECT_FOLDER + '/dt/daymet_median_v0')\
                 .filter(ee.Filter.calendarRange(self._doy, self._doy, 'day_of_year'))
@@ -529,6 +547,9 @@ def dt(self):
                 .filter(ee.Filter.calendarRange(self._doy, self._doy, 'day_of_year'))
             dt_img = ee.Image(dt_coll.first()).clamp(self._dt_min, self._dt_max)
         elif self._dt_source.upper() == 'CIMIS':
+            # CGM - Should we check this here or catch the exception in elev()
+            # if self._elev_source is None:
+            #     raise Exception('elev_source must be set if dt_source="CIMIS"')
             input_img = ee.Image(
                 ee.ImageCollection('projects/earthengine-legacy/assets/'
                                    'projects/climate-engine/cimis/daily')\

openet/ssebop/tests/test_c_image.py

@@ -75,15 +75,16 @@ def default_image_args(lst=305, ndvi=0.8,
                        et_reference_resample='nearest',
                        et_reference_date_type=None,
                        dt_source=18,
-                       elev_source=67,
-                       elr_flag=False,
                        tcorr_source=0.9744,
                        tmax_source=310.15,
+                       dt_scale_factor=None,
+                       elev_source=67,
+                       elr_flag=False,
+                       et_fraction_type='alfalfa',
+                       reflectance_type='TOA',
                        dt_resample='nearest',
                        tmax_resample='nearest',
                        tcorr_resample='nearest',
-                       et_fraction_type='alfalfa',
-                       reflectance_type='TOA',
                        ):
     return {
         'image': default_image(lst=lst, ndvi=ndvi),
@@ -93,15 +94,16 @@ def default_image_args(lst=305, ndvi=0.8,
         'et_reference_resample': et_reference_resample,
         'et_reference_date_type': et_reference_date_type,
         'dt_source': dt_source,
-        'elev_source': elev_source,
-        'elr_flag': elr_flag,
         'tcorr_source': tcorr_source,
         'tmax_source': tmax_source,
+        'dt_scale_factor': dt_scale_factor,
+        'elev_source': elev_source,
+        'elr_flag': elr_flag,
+        'et_fraction_type': et_fraction_type,
+        'reflectance_type': reflectance_type,
         'dt_resample': dt_resample,
         'tmax_resample': tmax_resample,
         'tcorr_resample': tcorr_resample,
-        'et_fraction_type': et_fraction_type,
-        'reflectance_type': reflectance_type,
     }
 
 
@@ -113,15 +115,16 @@ def default_image_obj(lst=305, ndvi=0.8,
                       et_reference_resample='nearest',
                       et_reference_date_type=None,
                       dt_source=18,
-                      elev_source=67,
-                      elr_flag=False,
                       tcorr_source=0.9744,
                       tmax_source=310.15,
+                      dt_scale_factor=None,
+                      elev_source=67,
+                      elr_flag=False,
+                      et_fraction_type='alfalfa',
+                      reflectance_type='TOA',
                       dt_resample='nearest',
                       tmax_resample='nearest',
                       tcorr_resample='nearest',
-                      et_fraction_type='alfalfa',
-                      reflectance_type='TOA',
                       ):
     return ssebop.Image(**default_image_args(
         lst=lst, ndvi=ndvi,
@@ -131,15 +134,16 @@ def default_image_obj(lst=305, ndvi=0.8,
         et_reference_resample=et_reference_resample,
         et_reference_date_type=et_reference_date_type,
         dt_source=dt_source,
-        elev_source=elev_source,
-        elr_flag=elr_flag,
         tcorr_source=tcorr_source,
         tmax_source=tmax_source,
+        dt_scale_factor=dt_scale_factor,
+        elev_source=elev_source,
+        elr_flag=elr_flag,
+        et_fraction_type=et_fraction_type,
+        reflectance_type=reflectance_type,
         dt_resample=dt_resample,
         tmax_resample=tmax_resample,
         tcorr_resample=tcorr_resample,
-        et_fraction_type=et_fraction_type,
-        reflectance_type=reflectance_type,
     ))
 
 
@@ -153,14 +157,15 @@ def test_Image_init_default_parameters():
     assert m._dt_source == 'projects/earthengine-legacy/assets/projects/usgs-ssebop/dt/daymet_median_v6'
     assert m._tcorr_source == 'FANO'
     assert m._tmax_source == 'projects/earthengine-legacy/assets/projects/usgs-ssebop/tmax/daymet_v4_mean_1981_2010'
-    assert m._elr_flag == False
     assert m._dt_min == 5
     assert m._dt_max == 25
-    assert m._dt_resample == 'bilinear'
+    assert m._dt_scale_factor == None
     assert m._elev_source == None
+    assert m._elr_flag == False
+    assert m.reflectance_type == 'SR'
+    assert m._dt_resample == 'bilinear'
     assert m._tmax_resample == 'bilinear'
     assert m._tcorr_resample == 'bilinear'
-    assert m.reflectance_type == 'SR'
 
 
 # Todo: Break these up into separate functions?
@@ -222,7 +227,9 @@ def test_Image_lst_properties():
 
 @pytest.mark.parametrize(
     'elev_source',
-    [None, '', 'DEADBEEF']
+    [None],
+    # TODO: Non-image strings should raise an exception
+    # ['', 'DEADBEEF']
     # TODO: Check what happens if source is an image collection
     # [None, '', 'DEADBEEF']
 )
@@ -356,6 +363,27 @@ def test_Image_dt_source_exception():
         utils.getinfo(default_image_obj(dt_source='').dt)
 
 
+@pytest.mark.parametrize(
+    'dt_source, factor, doy, xy, expected',
+    [
+        ['projects/usgs-ssebop/dt/daymet_median_v6', 0.01, SCENE_DOY, TEST_POINT, 20.77],
+        ['projects/usgs-ssebop/dt/daymet_median_v6', 1.0, SCENE_DOY, TEST_POINT, 2077],
+        # Scale factor is only applied to collection ID sources
+        ['projects/usgs-ssebop/dt/daymet_median_v2', 2.0, SCENE_DOY, TEST_POINT, 2 * 19.5982],
+        ['DAYMET_MEDIAN_V2', 2.0, SCENE_DOY, TEST_POINT, 19.5982],
+        # None will default to 0.01 for v6 and fall back to 1.0 for all other sources
+        ['projects/usgs-ssebop/dt/daymet_median_v6', None, SCENE_DOY, TEST_POINT, 20.77],
+        ['projects/usgs-ssebop/dt/daymet_median_v2', None, SCENE_DOY, TEST_POINT, 19.5982],
+    ]
+)
+def test_Image_dt_scale_factor(dt_source, factor, doy, xy, expected, tol=0.001):
+    """Test that dT scale factor changes the dT values"""
+    m = default_image_obj(dt_source=dt_source, dt_scale_factor=factor)
+    m._doy = doy
+    output = utils.point_image_value(ee.Image(m.dt), xy)
+    assert abs(output['dt'] - expected) <= tol
+
+
 @pytest.mark.parametrize(
     'doy, dt_min, dt_max',
     [