feat(KINSOL): Switch from Eigen to KINSOL

Previously QSE solving was done using Eigen. While this worked we were limited in the ability to use previous iterations to speed up later steps. We have switched to KINSOL, from SUNDIALS, for linear solving. This has drastically speed up the process of solving for QSE abundances, primarily because the jacobian matrix does not need to be generated every single time time a QSE abundance is requested.
2025-11-19 12:06:21 -05:00
parent f7fbc6c1da
commit 442d4ed86c
12 changed files with 506 additions and 386 deletions
--- a/src/include/gridfire/utils/sundials.h
+++ b/src/include/gridfire/utils/sundials.h
@@ -0,0 +1,66 @@
+#pragma once
+#include <unordered_map>
+#include <nvector/nvector_serial.h>
+
+#include "gridfire/exceptions/error_solver.h"
+#include "sundials/sundials_nvector.h"
+
+namespace gridfire::utils {
+    inline std::unordered_map<int, std::string> cvode_ret_code_map {
+        {0, "CV_SUCCESS: The solver succeeded."},
+        {1, "CV_TSTOP_RETURN: The solver reached the specified stopping time."},
+        {2, "CV_ROOT_RETURN: A root was found."},
+        {-99, "CV_WARNING: CVODE succeeded but in an unusual manner"},
+        {-1, "CV_TOO_MUCH_WORK: The solver took too many internal steps."},
+        {-2, "CV_TOO_MUCH_ACC: The solver could not satisfy the accuracy requested."},
+        {-3, "CV_ERR_FAILURE: The solver encountered a non-recoverable error."},
+        {-4, "CV_CONV_FAILURE: The solver failed to converge."},
+        {-5, "CV_LINIT_FAIL: The linear solver's initialization function failed."},
+        {-6, "CV_LSETUP_FAIL: The linear solver's setup function failed."},
+        {-7, "CV_LSOLVE_FAIL: The linear solver's solve function failed."},
+        {-8, "CV_RHSFUNC_FAIL: The right-hand side function failed in an unrecoverable manner."},
+        {-9, "CV_FIRST_RHSFUNC_ERR: The right-hand side function failed at the first call."},
+        {-10, "CV_REPTD_RHSFUNC_ERR: The right-hand side function repeatedly failed recoverable."},
+        {-11, "CV_UNREC_RHSFUNC_ERR: The right-hand side function failed unrecoverably."},
+        {-12, "CV_RTFUNC_FAIL: The rootfinding function failed in an unrecoverable manner."},
+        {-13, "CV_NLS_INIT_FAIL: The nonlinear solver's initialization function failed."},
+        {-14, "CV_NLS_SETUP_FAIL: The nonlinear solver's setup function failed."},
+        {-15, "CV_CONSTR_FAIL : The inequality constraint was violated and the solver was unable to recover."},
+        {-16, "CV_NLS_FAIL: The nonlinear solver's solve function failed."},
+        {-20, "CV_MEM_FAIL: Memory allocation failed."},
+        {-21, "CV_MEM_NULL: The CVODE memory structure is NULL."},
+        {-22, "CV_ILL_INPUT: An illegal input was detected."},
+        {-23, "CV_NO_MALLOC: The CVODE memory structure has not been allocated."},
+        {-24, "CV_BAD_K: The value of k is invalid."},
+        {-25, "CV_BAD_T: The value of t is invalid."},
+        {-26, "CV_BAD_DKY: The value of dky is invalid."},
+        {-27, "CV_TOO_CLOSE: The time points are too close together."},
+        {-28, "CV_VECTOROP_ERR: A vector operation failed."},
+        {-29, "CV_PROJ_MEM_NULL: The projection memory structure is NULL."},
+        {-30, "CV_PROJFUNC_FAIL: The projection function failed in an unrecoverable manner."},
+        {-31, "CV_REPTD_PROJFUNC_ERR: The projection function has repeated recoverable errors."}
+    };
+
+    inline void check_cvode_flag(const int flag, const std::string& func_name) {
+        if (flag < 0) {
+            if (!cvode_ret_code_map.contains(flag)) {
+                throw exceptions::CVODESolverFailureError("CVODE error in " + func_name + ": Unknown error code: " + std::to_string(flag));
+            }
+            throw exceptions::CVODESolverFailureError("CVODE error in " + func_name + ": " + cvode_ret_code_map.at(flag));
+        }
+    }
+
+    inline N_Vector init_sun_vector(uint64_t size, SUNContext sun_ctx) {
+        #ifdef SUNDIALS_HAVE_OPENMP
+            const N_Vector vec = N_VNew_OpenMP(size, 0, sun_ctx);
+        #elif SUNDIALS_HAVE_PTHREADS
+            const N_Vector vec = N_VNew_Pthreads(size, sun_ctx);
+        #else
+            const N_Vector vec = N_VNew_Serial(static_cast<long long>(size), sun_ctx);
+        #endif
+
+        check_cvode_flag(vec == nullptr ? -1 : 0, "N_VNew");
+        return vec;
+    }
+
+}