Snapshot optimized solver and audit diagnostics before numerical experiments

sandbox.cpp

@@ -3,6 +3,7 @@
 #include <iostream>
 #include <numbers>
 #include <stdexcept>
+#include <string_view>
 #include <utility>
 
 #include <mfem.hpp>
@@ -52,6 +53,20 @@ int main(
     int argc,
     char **argv
 ) {
+    bool geometryPreflight = true;
+    for (int i = 1; i < argc; ++i) {
+        const std::string_view option(argv[i]);
+        if (option == "--skip-preflight") geometryPreflight = false;
+        else if (option == "--preflight") geometryPreflight = true;
+        else if (option == "--help") {
+            std::cout << "Usage: sandbox [--skip-preflight|--preflight]\n"
+                         "Trial geometry validation and backtracking remain enabled.\n";
+            return 0;
+        } else {
+            std::cerr << "Unknown sandbox option: " << option << '\n';
+            return 2;
+        }
+    }
     mfem::Mpi::Init(argc, argv);
     int exitCode = 0;
 
@@ -77,13 +92,16 @@ int main(
 
         constexpr double radius                = utils::RADIUS;
         constexpr double mass                  = utils::MASS;
-        constexpr double angularMomentum       = 0.1;
+        constexpr double angularMomentum       = 0.00;
         constexpr double gravitationalConstant = utils::G;
         const double polytropicConstant =
             2.0 * gravitationalConstant * radius * radius / std::numbers::pi_v<double>;
+        // const double polytropicConstant = 0.3639391; // Use for n=3 test
+
         std::println("K = {}", polytropicConstant);
         const double centralDensity =
             std::numbers::pi_v<double> * mass / (4.0 * radius * radius * radius);
+        //const double centralDensity =12.9351146; // use for n=3 test
 
         auto stellarModel = model::StellarModel(
             eos::Polytrope({.n = 1.0, .K = polytropicConstant}),
@@ -201,9 +219,10 @@ int main(
                       .absoluteTolerance = 0.0,
                       .maximumIterations = 200
             },
-            .backtracking = {}
+            .backtracking = {.geometryPreflight = geometryPreflight}
         });
 
+        if (rank == 0) std::cout << "Geometry preflight: " << (geometryPreflight ? "enabled" : "skipped") << '\n';
         auto equilibriumSolver  = solver::make(context, nonlinearSolver, observer);
         const auto evaluateStart = std::chrono::steady_clock::now();
         auto report              = equilibriumSolver.evaluate();