update fs coeffs, add fs tests

Author: wholmgren

pvlib/atmosphere.py

@@ -406,12 +406,12 @@ def first_solar_spectral_correction(pw, airmass_absolute, module_type=None,
 
     _coefficients = {}
     _coefficients['cdte'] = (
-        0.8752, -0.04588, -0.01559, 0.08751, 0.09158, -0.002295)
+        0.87102, -0.040543, -0.00929202, 0.10052, 0.073062, -0.0034187)
     _coefficients['monosi'] = (
-        0.8478, -0.03326, -0.0022953, 0.1565, 0.01566, -0.001712)
+        0.86588, -0.021637, -0.0030218, 0.12081, 0.017514, -0.0012610)
     _coefficients['xsi'] = _coefficients['monosi']
     _coefficients['polysi'] = (
-        0.83019, -0.04063, -0.005281, 0.1695, 0.02974, -0.001676)
+        0.84674, -0.028568, -0.0051832, 0.13669, 0.029234, -0.0014207)
     _coefficients['multisi'] = _coefficients['polysi']
 
     if module_type is not None and coefficients is None:

pvlib/test/test_atmosphere.py

@@ -6,6 +6,7 @@
 
 from nose.tools import raises
 from nose.tools import assert_almost_equals
+from numpy.testing import assert_allclose
 
 from pvlib.location import Location
 from pvlib import solarposition
@@ -75,4 +76,44 @@ def test_gueymard94_pw():
         [  0.1       ,   0.33702061,   1.12340202,   0.1       ,
          1.12040963,   3.73469877,   0.1       ,   3.44859767,  11.49532557])
 
-    np.testing.assert_allclose(pws, expected, atol=0.01)
+    assert_allclose(pws, expected, atol=0.01)
+
+
+def test_first_solar_spectral_correction():
+    ams = np.array([1, 3, 5])
+    pws = np.array([1, 3, 5])
+    ams, pws = np.meshgrid(ams, pws)
+
+    expect = {}
+    expect['cdte'] = np.array(
+        [[ 0.99134828,  0.97701063,  0.93975103],
+         [ 1.02852847,  1.01874908,  0.98604776],
+         [ 1.04722476,  1.03835703,  1.00656735]])
+    expect['monosi'] = np.array(
+        [[ 0.9782842 ,  1.02092726,  1.03602157],
+         [ 0.9859024 ,  1.0302268 ,  1.04700244],
+         [ 0.98885429,  1.03351495,  1.05062687]])
+    expect['polysi'] = np.array(
+        [[ 0.9774921 ,  1.01757872,  1.02649543],
+         [ 0.98947361,  1.0314545 ,  1.04226547],
+         [ 0.99403107,  1.03639082,  1.04758064]])
+
+    def run_fs_test(module_type):
+        out = atmosphere.first_solar_spectral_correction(pws, ams, module_type)
+        assert_allclose(out, expect[module_type], atol=0.001)
+
+    for module_type in expect.keys():
+        yield run_fs_test, module_type
+
+
+def test_first_solar_spectral_correction_supplied():
+    # use the cdte coeffs
+    coeffs = (0.87102, -0.040543, -0.00929202, 0.10052, 0.073062, -0.0034187)
+    out = atmosphere.first_solar_spectral_correction(1, 1, coefficients=coeffs)
+    expected = 0.99134828
+    assert_allclose(out, expected, atol=1e-3)
+
+
+@raises(TypeError)
+def test_first_solar_spectral_correction_ambiguous():
+    atmosphere.first_solar_spectral_correction(1, 1)