feat(mean_field): added initial implementation

note this implementation lacks many tests

libmeanfield/interface/utils/misc.cppm

@@ -0,0 +1,101 @@
+module;
+#include <string_view>
+#include <functional>
+#include <expected>
+
+#include <mfem.hpp>
+
+#include "xad_promote_polyfill.h"
+#include <XAD/XAD.hpp>
+
+export module mean_field:utils.misc;
+import :boundary.contexts;
+
+export namespace mean_field::utils {
+    constexpr double APPROX_MAX_ACCEPTABLE_POTENTIAL_ERROR_SI_BURNING = 1e-4;
+
+
+    bool is_vacuum(const mfem::ElementTransformation &Tr, mfem::Array<mfem::Vector*> elvec) {
+        if (Tr.Attribute == 3) {
+            const int size_elvec = elvec.Size();
+            for (int i = 0; i < size_elvec; i++) {
+                if (elvec[i]) {
+                    *elvec[i] = 0.0;
+                }
+            }
+            return true;
+        }
+        return false;
+    }
+
+    constexpr std::string_view ANSI_GREEN = "\033[32m";
+    constexpr std::string_view ANSI_RED = "\033[31m";
+    constexpr std::string_view ANSI_YELLOW = "\033[33m";
+    constexpr std::string_view ANSI_BLUE = "\033[34m";
+    constexpr std::string_view ANSI_MAGENTA = "\033[35m";
+    constexpr std::string_view ANSI_CYAN = "\033[36m";
+    constexpr std::string_view ANSI_RESET = "\033[0m";
+    constexpr std::string_view ANSI_BCYAN = "\033[1;36m";
+
+
+    constexpr double G = 1.0;
+    constexpr double MASS = 1.0;
+    constexpr double RADIUS = 1.0;
+
+    [[maybe_unused]] constexpr char HOST[10] = "localhost";
+    [[maybe_unused]] constexpr int PORT = 19916;
+
+
+    template<typename T>
+    concept is_xad =
+            std::is_same_v<T, xad::AReal<long double> >
+            || std::is_same_v<T, xad::AReal<double> >
+            || std::is_same_v<T, xad::AReal<float> >;
+
+    template<typename T>
+    concept is_real = std::is_floating_point_v<T> || is_xad<T>;
+
+    template<is_real T>
+    using EOS_P = std::function<T(const T& rho, const T& temp)>;
+
+    enum class DOMAINS : uint8_t {
+        CORE = 1 << 0,
+        ENVELOPE = 1 << 1,
+        VACUUM = 1 << 2,
+        STELLAR = CORE | ENVELOPE,
+        ALL = CORE | ENVELOPE | VACUUM
+    };
+
+
+    DOMAINS operator|(
+        DOMAINS lhs,
+        DOMAINS rhs
+    );
+
+    DOMAINS operator&(
+        DOMAINS lhs,
+        DOMAINS rhs
+    );
+
+    void populate_element_mask(
+        const mfem::Mesh* mesh,
+        DOMAINS domain,
+        mfem::Array<int> &mask
+    );
+
+    void populate_domain_tdofs(
+        const mfem::ParFiniteElementSpace *fes,
+        const mfem::Array<int> &element_mask,
+        mfem::Array<int> &ess_tdof
+    );
+
+    std::expected<boundary::Bounds, boundary::BoundsError> discover_bounds(
+        const mfem::Mesh *mesh,
+        int vacuum_attr
+    );
+
+    int get_mesh_order(
+        const mfem::Mesh &mesh
+    );
+
+}