feat(poly): added first pass implimentation of 3D constrained lane-emden solver

This has not currently been tested and this commit should not be viewed as scientifically complete

src/poly/coeff/public/polyCoeff.h

@@ -1,8 +1,35 @@
+#ifndef POLYCOEFF_H
+#define POLYCOEFF_H
+
 #include "mfem.hpp"
 #include <cmath>
 
-double xi_coeff_func(const mfem::Vector &x);
+namespace polycoeff
+{
+  /**
+   * @brief Computes the xi coefficient function.
+   * 
+   * @param x Input vector.
+   * @return double The computed xi coefficient.
+   */
+    double xi_coeff_func(const mfem::Vector &x);
 
-void vec_xi_coeff_func(const mfem::Vector &x, mfem::Vector &v);
+  /**
+   * @brief Computes the vector xi coefficient function.
+   * 
+   * @param x Input vector.
+   * @param v Output vector to store the computed xi coefficient.
+   */
+    void vec_xi_coeff_func(const mfem::Vector &x, mfem::Vector &v);
 
-double theta_initial_guess(const mfem::Vector &x, double root);
+  /**
+   * @brief Computes the initial guess for theta.
+   * 
+   * @param x Input vector.
+   * @param root Root value used in the computation.
+   * @return double The initial guess for theta.
+   */
+    double theta_initial_guess(const mfem::Vector &x, double root);
+} // namespace polyCoeff
+
+#endif // POLYCOEFF_H