Merge pull request #100 from rahil-makadia/dev

python level orbital element partials

Author: rahil-makadia

grss/version.txt

@@ -1 +1 @@
-4.5.0
+4.5.1

src/elements.cpp

@@ -450,7 +450,7 @@ void get_elements_partials(const real &epochMjd, const std::vector<real> &elems,
             M = std::numeric_limits<real>::quiet_NaN();
         }
     } else {
-        throw std::invalid_argument("get_cartesian_partials: invalid conversion "
+        throw std::invalid_argument("get_elements_partials: invalid conversion "
                                     "type, must be com2cart or kep2cart");
     }
     const std::vector<real> kep = {a, e, i, om, w, nu};

src/grss.cpp

@@ -398,6 +398,35 @@ PYBIND11_MODULE(libgrss, m) {
             Cometary state vector.
         )mydelimiter");
 
+    m.def(
+        "get_elements_partials",
+        [](real epochMjd, std::vector<real> elems, std::string conversion, real GM) {
+            std::vector<std::vector<real>> partials(6, std::vector<real>(6));
+            get_elements_partials(epochMjd, elems, conversion, partials, GM);
+            return partials;
+        },
+        py::arg("epochMjd"), py::arg("elems"), py::arg("conversion"),
+        py::arg("GM") = 2.9591220828559115e-4L, R"mydelimiter(
+        Calculate the partial derivatives of input ecliptic orbital elements with respect to
+        the corresponding ecliptic Cartesian state vector.
+
+        Parameters
+        ----------
+        epochMjd : real
+            Epoch in modified Julian date.
+        elems : list of real
+            Orbital elements vector (either Keplerian [a,e,i,OM,om,nu] or cometary [e,q,tp,OM,om,i]) with angles in radians.
+        conversion : str
+            Conversion type (must be either "kep2cart" or "com2cart").
+        GM : real, optional
+            Gravitational parameter of the central body, by default 0.00029591220828559115L.
+
+        Returns
+        -------
+        partials : list of list of real
+            Partial derivatives of orbital elements.
+        )mydelimiter");
+
     m.def(
         "matrix_inverse",
         [](std::vector<std::vector<real>> mat, const real &tol) {