math.tau for clarity

Author: scivision

src/pymap3d/ecef.py

@@ -3,21 +3,11 @@
 import typing
 
 try:
-    from numpy import (
-        radians,
-        sin,
-        cos,
-        tan,
-        arctan as atan,
-        hypot,
-        degrees,
-        arctan2 as atan2,
-        sqrt,
-        pi,
-    )
+    from numpy import radians, sin, cos, tan, arctan as atan, hypot, degrees, arctan2 as atan2, sqrt
 except ImportError:
-    from math import radians, sin, cos, tan, atan, hypot, degrees, atan2, sqrt, pi  # type: ignore
+    from math import radians, sin, cos, tan, atan, hypot, degrees, atan2, sqrt  # type: ignore
 
+from math import pi
 from datetime import datetime
 
 from .ellipsoid import Ellipsoid
@@ -31,9 +21,6 @@
 if typing.TYPE_CHECKING:
     from numpy import ndarray
 
-# py < 3.6 compatible
-tau = 2 * pi
-
 
 __all__ = [
     "geodetic2ecef",

src/pymap3d/sidereal.py

@@ -1,6 +1,6 @@
 # Copyright (c) 2014-2018 Michael Hirsch, Ph.D.
 """ manipulations of sidereal time """
-from math import pi
+from math import tau
 from datetime import datetime
 
 from .timeconv import str2dt
@@ -128,4 +128,4 @@ def greenwichsrt(Jdate: float) -> float:
     )
 
     # 1/86400 and %(2*pi) implied by units of radians
-    return gmst_sec * (2 * pi) / 86400.0 % (2 * pi)
+    return gmst_sec * tau / 86400.0 % tau