remove list input

Author: jason-rpkt

pvlib/iam.py

@@ -470,6 +470,10 @@ def interp(aoi, theta_ref, iam_ref, method='linear', normalize=True):
     pvlib.iam.sapm
     '''
     # Contributed by Anton Driesse (@adriesse), PV Performance Labs. July, 2019
+    if isinstance(theta_ref, list):
+        raise TypeError("theta_ref cannot be a list")
+    if isinstance(iam_ref, list):
+        raise TypeError("iam_ref cannot be a list")
     # Scipy doesn't give the clearest feedback, so check number of points here.
     MIN_REF_VALS = {'linear': 2, 'quadratic': 3, 'cubic': 4, 1: 2, 2: 3, 3: 4}
 
@@ -481,9 +485,6 @@ def interp(aoi, theta_ref, iam_ref, method='linear', normalize=True):
         raise ValueError("Negative value(s) found in 'iam_ref'. "
                          "This is not physically possible.")
 
-    theta_ref = np.asarray(theta_ref)
-    iam_ref = np.asarray(iam_ref)
-
     if method == "linear":
         interpolator = make_interp_spline(theta_ref, iam_ref, k=1)
 

tests/test_iam.py

@@ -171,8 +171,8 @@ def test_martin_ruiz_diffuse():
 
 def test_iam_interp():
 
-    aoi_meas = [0.0, 45.0, 65.0, 75.0]
-    iam_meas = [1.0,  0.9,  0.8,  0.6]
+    aoi_meas = np.array([0.0, 45.0, 65.0, 75.0])
+    iam_meas = np.array([1.0,  0.9,  0.8,  0.6])
 
     # simple default linear method
     aoi = 55.0
@@ -200,18 +200,18 @@ def test_iam_interp():
     assert_series_equal(iam, expected)
 
     # check beyond reference values
-    aoi = [-45, 0, 45, 85, 90, 95, 100, 105, 110]
-    expected = [0.9, 1.0, 0.9, 0.4, 0.3, 0.2, 0.1, 0.0, 0.0]
+    aoi = np.array([-45, 0, 45, 85, 90, 95, 100, 105, 110])
+    expected = np.array([0.9, 1.0, 0.9, 0.4, 0.3, 0.2, 0.1, 0.0, 0.0])
     iam = _iam.interp(aoi, aoi_meas, iam_meas)
     assert_allclose(iam, expected)
 
     # check exception clause
     with pytest.raises(ValueError):
-        _iam.interp(0.0, [0], [1])
+        _iam.interp(0.0, np.array([0]), np.array([1]))
 
     # check exception clause
     with pytest.raises(ValueError):
-        _iam.interp(0.0, [0, 90], [1, -1])
+        _iam.interp(0.0, np.array([0, 90]), np.array([1, -1]))
 
     # check linear after updating interp1d
     theta_ref = np.array([0, 60, 90])
@@ -239,6 +239,14 @@ def test_iam_interp():
     expected = 1.0 - 1e-4 * aoi**2
     np.testing.assert_allclose(iam, expected, rtol=1e-12)
 
+    # check exception clause - list input for theta_ref
+    with pytest.raises(TypeError):
+        _iam.interp(0.0, [0, 60, 90], np.array([1.0, 0.8, 0.0]))
+
+    # check exception clause - list input for iam_ref
+    with pytest.raises(TypeError):
+        _iam.interp(0.0, np.array([0, 60, 90]), [1.0, 0.8, 0.0])
+
 
 @pytest.mark.parametrize('aoi,expected', [
     (45, 0.9975036250000002),