spec and ext rebin_contres tests

measure_extinction/tests/test_rebin.py

@@ -0,0 +1,78 @@
+import numpy as np
+import astropy.units as u
+
+from measure_extinction.stardata import SpecData
+from measure_extinction.extdata import ExtData
+from measure_extinction.merge_obsspec import _wavegrid
+
+
+def test_spec_rebin_constres():
+    spec = SpecData("TEST")
+
+    # fake some simple data
+    # flux values alternate between 1 and 2
+    tres = 1000
+    twaves, tmp, tmp = _wavegrid(tres, [1.001, 10.0])
+    spec.waves = twaves * u.micron
+    n_test = len(twaves)
+    a = np.full((n_test // 2), 1.0)
+    b = np.full((n_test // 2), 2.0)
+    spec.fluxes = np.empty((a.size + b.size), dtype=a.dtype)
+    spec.fluxes[0::2] = a
+    spec.fluxes[1::2] = b
+    spec.fluxes *= u.erg / ((u.cm ** 2) * u.s * u.angstrom)
+    spec.uncs = spec.fluxes * 0.05
+    spec.npts = np.full((n_test), 1)
+
+    # rebin it using the ExtData member function
+    gres = tres / 2.0
+    rwaverange = [1.0, 10.0] * u.micron
+    spec.rebin_constres(rwaverange, gres)
+
+    ndelt = spec.waves[1:] - spec.waves[0:-1]
+    nwave = 0.5 * (spec.waves[1:] + spec.waves[0:-1])
+    nres = nwave / ndelt
+
+    # not quite the same, but very close
+    np.testing.assert_allclose(nres, np.full(len(nres), gres), rtol=0.001)
+
+    # test all but the end elements as edge effects mean they will be different
+    np.testing.assert_equal(spec.fluxes[1:-1].value, np.full(len(nres) - 1, 1.2))
+
+
+def test_ext_rebin_constres():
+    ext = ExtData()
+
+    # fake some simple data
+    # ext values alternate between 1 and 2
+    tres = 1000
+    twaves, tmp, tmp = _wavegrid(tres, [1.001, 10.0])
+    ext.waves["TEST"] = twaves * u.micron
+    n_test = len(twaves)
+    a = np.full((n_test // 2), 1.0)
+    b = np.full((n_test // 2), 2.0)
+    ext.exts["TEST"] = np.empty((a.size + b.size), dtype=a.dtype)
+    ext.exts["TEST"][0::2] = a
+    ext.exts["TEST"][1::2] = b
+    ext.uncs["TEST"] = ext.exts["TEST"] * 0.05
+    ext.npts["TEST"] = np.full((n_test), 1)
+
+    # rebin it using the ExtData member function
+    gres = tres / 2.0
+    rwaverange = [1.0, 10.0] * u.micron
+    ext.rebin_constres("TEST", rwaverange, gres)
+
+    ndelt = ext.waves["TEST"][1:] - ext.waves["TEST"][0:-1]
+    nwave = 0.5 * (ext.waves["TEST"][1:] + ext.waves["TEST"][0:-1])
+    nres = nwave / ndelt
+
+    # not quite the same, but very close
+    np.testing.assert_allclose(nres, np.full(len(nres), gres), rtol=0.001)
+
+    # test all but the end elements as edge effects mean they will be different
+    # weighted average with fractional weights gives 1.2 (equal weights would give 1.5)
+    np.testing.assert_equal(ext.exts["TEST"][1:-1], np.full(len(nres) - 1, 1.2))
+
+
+if __name__ == "__main__":
+    test_spec_rebin_constres()