Don't skip Beta calculation if some values would divide-by-zero.

If one or more values would divide by zero and needs to use a fallback Beta
value, it's still necessary to calculate the correct Beta for any other values
that would have succeeded. Previously, this used the same fallback value for all
positions if even just one failed.

Author: adamshapiro0

src/pymap3d/ecef.py

@@ -5,7 +5,7 @@
 import warnings
 
 try:
-    from numpy import asarray, finfo, where
+    from numpy import asarray, finfo, full_like, logical_and, logical_or, ndarray, where
 
     from .eci import ecef2eci, eci2ecef
 except ImportError:
@@ -144,16 +144,24 @@ def ecef2geodetic(
 
     # eqn. 4b
     try:
+        calculated_idx = full_like(z, False)
+        Beta = ndarray(z.shape)
         with warnings.catch_warnings(record=True):
             warnings.simplefilter("error")
-            Beta = atan(huE / u * z / hypot(x, y))
+            # Preempt any possible divide-by-zero errors by only calculating values that will succeed. Then, below, use
+            # the fallback Beta values for any values that would have failed.
+            xy_hypot = hypot(x, y)
+            calculated_idx = ~logical_or(isclose(u, 0), isclose(xy_hypot, 0))
+            Beta[calculated_idx] = atan(huE[calculated_idx] / u[calculated_idx] * z[calculated_idx] /
+                                        xy_hypot[calculated_idx])
     except (ArithmeticError, RuntimeWarning):
-        if any(isclose(z, 0)):
-            Beta = 0
-        elif z > 0:
-            Beta = pi / 2
-        else:
-            Beta = -pi / 2
+        pass
+
+    if not all(calculated_idx):
+        not_calculated_idx = ~calculated_idx
+        Beta[logical_and(not_calculated_idx, z > 0)] = pi / 2
+        Beta[logical_and(not_calculated_idx, z < 0)] = -pi / 2
+        Beta[logical_and(not_calculated_idx, isclose(z, 0))] = 0
 
     # eqn. 13
     dBeta = ((ell.semiminor_axis * u - ell.semimajor_axis * huE + E**2) * sin(Beta)) / (