ecef2eci: scalar output for scalar input with Numpy backend

add test for Numpy and AstroPy backends

Author: scivision

src/pymap3d/eci.py

@@ -54,25 +54,7 @@ def eci2ecef_astropy(x, y, z, t: datetime) -> tuple:
     """
     eci2ecef using Astropy
 
-    Parameters
-    ----------
-    x : float
-        ECI x-location [meters]
-    y : float
-        ECI y-location [meters]
-    z : float
-        ECI z-location [meters]
-    t : datetime.datetime
-        time of obsevation (UTC)
-
-    Results
-    -------
-    x_ecef : float
-        x ECEF coordinate
-    y_ecef : float
-        y ECEF coordinate
-    z_ecef : float
-        z ECEF coordinate
+    see eci2ecef() for description
     """
 
     gcrs = GCRS(CartesianRepresentation(x * u.m, y * u.m, z * u.m), obstime=t)
@@ -89,27 +71,7 @@ def eci2ecef_numpy(x, y, z, t: datetime) -> tuple:
     """
     eci2ecef using Numpy
 
-    less accurate than astropy, but may be good enough.
-
-    Parameters
-    ----------
-    x : float
-        ECI x-location [meters]
-    y : float
-        ECI y-location [meters]
-    z : float
-        ECI z-location [meters]
-    t : datetime.datetime
-        time of obsevation (UTC)
-
-    Results
-    -------
-    x_ecef : float
-        x ECEF coordinate
-    y_ecef : float
-        y ECEF coordinate
-    z_ecef : float
-        z ECEF coordinate
+    see eci2ecef() for description
     """
 
     x = numpy.atleast_1d(x)
@@ -165,33 +127,50 @@ def ecef2eci(x, y, z, time: datetime) -> tuple:
     """
 
     try:
-        itrs = ITRS(CartesianRepresentation(x * u.m, y * u.m, z * u.m), obstime=time)
-        gcrs = itrs.transform_to(GCRS(obstime=time))
-        eci = EarthLocation(*gcrs.cartesian.xyz)
-
-        x_eci = eci.x.value
-        y_eci = eci.y.value
-        z_eci = eci.z.value
+        return ecef2eci_astropy(x, y, z, time)
     except NameError:
-        x = numpy.atleast_1d(x)
-        y = numpy.atleast_1d(y)
-        z = numpy.atleast_1d(z)
-        gst = numpy.atleast_1d(greenwichsrt(juliandate(time)))
-        assert x.shape == y.shape == z.shape
-        assert x.size == gst.size
-
-        ecef = numpy.column_stack((x.ravel(), y.ravel(), z.ravel()))
-        eci = numpy.empty((x.size, 3))
-        for i in range(x.size):
-            eci[i, :] = R3(gst[i]).T @ ecef[i, :]
-
-        x_eci = eci[:, 0].reshape(x.shape)
-        y_eci = eci[:, 1].reshape(y.shape)
-        z_eci = eci[:, 2].reshape(z.shape)
+        return ecef2eci_numpy(x, y, z, time)
+
+
+def ecef2eci_astropy(x, y, z, t: datetime) -> tuple:
+    """ecef2eci using Astropy
+    see ecef2eci() for description
+    """
+    itrs = ITRS(CartesianRepresentation(x * u.m, y * u.m, z * u.m), obstime=t)
+    gcrs = itrs.transform_to(GCRS(obstime=t))
+    eci = EarthLocation(*gcrs.cartesian.xyz)
+
+    x_eci = eci.x.value
+    y_eci = eci.y.value
+    z_eci = eci.z.value
 
     return x_eci, y_eci, z_eci
 
 
+def ecef2eci_numpy(x, y, z, t: datetime) -> tuple:
+    """ecef2eci using Numpy
+    see ecef2eci() for description
+    """
+
+    x = numpy.atleast_1d(x)
+    y = numpy.atleast_1d(y)
+    z = numpy.atleast_1d(z)
+    gst = numpy.atleast_1d(greenwichsrt(juliandate(t)))
+    assert x.shape == y.shape == z.shape
+    assert x.size == gst.size
+
+    ecef = numpy.column_stack((x.ravel(), y.ravel(), z.ravel()))
+    eci = numpy.empty((x.size, 3))
+    for i in range(x.size):
+        eci[i, :] = R3(gst[i]).T @ ecef[i, :]
+
+    x_eci = eci[:, 0].reshape(x.shape)
+    y_eci = eci[:, 1].reshape(y.shape)
+    z_eci = eci[:, 2].reshape(z.shape)
+
+    return x_eci.squeeze()[()], y_eci.squeeze()[()], z_eci.squeeze()[()]
+
+
 def R3(x: float):
     """Rotation matrix for ECI"""
     return numpy.array(

src/pymap3d/tests/test_eci.py

@@ -55,9 +55,35 @@ def test_ecef2eci():
     # this example from Matlab ecef2eci docs
     eci = pm.ecef2eci(*ECEF, UTC)
 
-    rel = 0.01 if astropy is None else 0.0001
+    assert isinstance(eci[0], float)
+    assert isinstance(eci[1], float)
+    assert isinstance(eci[2], float)
+
+
+def test_ecef2eci_numpy():
+    pytest.importorskip("numpy")
+
+    eci = pm.eci.ecef2eci_numpy(*ECEF, UTC)
+
+    rel = 0.025
+
+    assert eci == approx(ECI, rel=rel)
+    assert isinstance(eci[0], float)
+    assert isinstance(eci[1], float)
+    assert isinstance(eci[2], float)
+
+
+def test_ecef2eci_astropy():
+    pytest.importorskip("astropy")
+
+    eci = pm.eci.ecef2eci_astropy(*ECEF, UTC)
+
+    rel = 0.0001
 
-    assert eci == approx([-2981810.6, 5207039.5, 3161595.1], rel=rel)
+    assert eci == approx(ECI, rel=rel)
+    assert isinstance(eci[0], float)
+    assert isinstance(eci[1], float)
+    assert isinstance(eci[2], float)
 
 
 def test_eci2geodetic():