Improves pure-Python ECI/ECEF accuracy

src/pymap3d/__init__.py

@@ -88,7 +88,17 @@
     geoc2geod,
 )
 
-from .nvector import geodetic2nvector, nvector2geodetic, ecef2nvector, nvector2ecef
+from .nvector import (
+    geodetic2nvector,
+    nvector2geodetic,
+    ecef2nvector,
+    nvector2ecef,
+    nvector_distance,
+    nvector_interpolate,
+    nvector_mean,
+    nvector_cross_track_distance,
+    nvector_intersection,
+)
 
 from .rcurve import parallel, meridian, transverse, geocentric_radius
 
@@ -158,6 +168,11 @@
     "dca2geodetic",
     "aer2dca",
     "dca2aer",
+    "nvector_distance",
+    "nvector_interpolate",
+    "nvector_mean",
+    "nvector_cross_track_distance",
+    "nvector_intersection",
 ]
 
 

src/pymap3d/aer.py

@@ -170,9 +170,23 @@ def aer2geodetic(
     return ecef2geodetic(x, y, z, ell=ell, deg=deg)
 
 
-def eci2aer(x, y, z, lat0, lon0, h0, t: datetime, *, deg: bool = True) -> tuple:
+def eci2aer(
+    x,
+    y,
+    z,
+    lat0,
+    lon0,
+    h0,
+    t: datetime,
+    *,
+    deg: bool = True,
+    delta_ut1: float = 0.0,
+    xp: float = 0.0,
+    yp: float = 0.0,
+) -> tuple:
     """
-    takes Earth Centered Inertial x,y,z ECI coordinates of point and gives az, el, slant range from Observer
+    takes Earth Centered Inertial x,y,z ECI coordinates of point and gives az, el,
+    slant range from Observer
 
     Parameters
     ----------
@@ -193,6 +207,12 @@ def eci2aer(x, y, z, lat0, lon0, h0, t: datetime, *, deg: bool = True) -> tuple:
         Observation time
     deg : bool, optional
         true: degrees, false: radians
+    delta_ut1 : float, optional
+        UT1-UTC in seconds for the pure-Python path. Defaults to ``0.0``.
+    xp : float, optional
+        Polar motion x coordinate in arcseconds for the pure-Python path.
+    yp : float, optional
+        Polar motion y coordinate in arcseconds for the pure-Python path.
 
     Returns
     -------
@@ -204,7 +224,7 @@ def eci2aer(x, y, z, lat0, lon0, h0, t: datetime, *, deg: bool = True) -> tuple:
          slant range [meters]
     """
 
-    xe, ye, ze = eci2ecef(x, y, z, t)
+    xe, ye, ze = eci2ecef(x, y, z, t, delta_ut1=delta_ut1, xp=xp, yp=yp)
 
     return ecef2aer(xe, ye, ze, lat0, lon0, h0, deg=deg)
 
@@ -220,6 +240,9 @@ def aer2eci(
     ell: Ellipsoid | None = None,
     *,
     deg: bool = True,
+    delta_ut1: float = 0.0,
+    xp: float = 0.0,
+    yp: float = 0.0,
 ) -> tuple:
     """
     gives ECI of a point from an observer at az, el, slant range
@@ -244,6 +267,12 @@ def aer2eci(
           reference ellipsoid
     deg : bool, optional
           degrees input/output  (False: radians in/out)
+    delta_ut1 : float, optional
+        UT1-UTC in seconds for the pure-Python path. Defaults to ``0.0``.
+    xp : float, optional
+        Polar motion x coordinate in arcseconds for the pure-Python path.
+    yp : float, optional
+        Polar motion y coordinate in arcseconds for the pure-Python path.
 
     Returns
     -------
@@ -260,7 +289,7 @@ def aer2eci(
 
     x, y, z = aer2ecef(az, el, srange, lat0, lon0, h0, ell, deg=deg)
 
-    return ecef2eci(x, y, z, t)
+    return ecef2eci(x, y, z, t, delta_ut1=delta_ut1, xp=xp, yp=yp)
 
 
 def aer2ecef(

src/pymap3d/azelradec.py

@@ -28,6 +28,8 @@ def azel2radec(
     lon_deg: float,
     time: datetime,
     force_non_astropy: bool = False,
+    *,
+    delta_ut1: float = 0.0,
 ) -> tuple[float, float]:
     """
     viewing angle (az, el) to sky coordinates (ra, dec)
@@ -56,7 +58,9 @@ def azel2radec(
     """
 
     if force_non_astropy or "astropy" not in sys.modules:
-        return vazel2radec(az_deg, el_deg, lat_deg, lon_deg, time)
+        return vazel2radec(
+            az_deg, el_deg, lat_deg, lon_deg, time, delta_ut1=delta_ut1
+        )
     else:
         return azel2radec_astropy(az_deg, el_deg, lat_deg, lon_deg, time)
 
@@ -85,6 +89,8 @@ def radec2azel(
     lon_deg: float,
     time: datetime,
     force_non_astropy: bool = False,
+    *,
+    delta_ut1: float = 0.0,
 ) -> tuple[float, float]:
     """
     sky coordinates (ra, dec) to viewing angle (az, el)
@@ -113,7 +119,9 @@ def radec2azel(
     """
 
     if force_non_astropy or "astropy" not in sys.modules:
-        return vradec2azel(ra_deg, dec_deg, lat_deg, lon_deg, time)
+        return vradec2azel(
+            ra_deg, dec_deg, lat_deg, lon_deg, time, delta_ut1=delta_ut1
+        )
     else:
         return radec2azel_astropy(ra_deg, dec_deg, lat_deg, lon_deg, time)