added -nlssMaxDensity and -nlssMinSize simulation flags

Author: Willi

SimulationRuntime/c/simulation/simulation_runtime.cpp

@@ -845,6 +845,14 @@ int initRuntimeAndSimulation(int argc, char**argv, DATA *data, threadData_t *thr
     linearSparseSolverMinSize = atoi(omc_flagValue[FLAG_LSS_MIN_SIZE]);
     infoStreamPrint(LOG_STDOUT, 0, "Maximum system size for using linear sparse solver changed to %d", linearSparseSolverMinSize);
   }
+  if(omc_flag[FLAG_NLS_MAX_DENSITY]) {
+    nonlinearSparseSolverMaxDensity = atof(omc_flagValue[FLAG_NLS_MAX_DENSITY]);
+    infoStreamPrint(LOG_STDOUT, 0, "Maximum density for using non-linear sparse solver changed to %f", nonlinearSparseSolverMaxDensity);
+  }
+  if(omc_flag[FLAG_NLS_MIN_SIZE]) {
+    nonlinearSparseSolverMinSize = atoi(omc_flagValue[FLAG_NLS_MIN_SIZE]);
+    infoStreamPrint(LOG_STDOUT, 0, "Maximum system size for using non-linear sparse solver changed to %d", nonlinearSparseSolverMinSize);
+  }
   if(omc_flag[FLAG_NEWTON_XTOL]) {
     newtonXTol = atof(omc_flagValue[FLAG_NEWTON_XTOL]);
     infoStreamPrint(LOG_STDOUT, 0, "Tolerance for updating solution vector in Newton solver changed to %g", newtonXTol);

SimulationRuntime/c/simulation/solver/model_help.c

@@ -53,6 +53,8 @@
 int maxEventIterations = 20;
 double linearSparseSolverMaxDensity = 0.2;
 int linearSparseSolverMinSize = 4001;
+double nonlinearSparseSolverMaxDensity = 0.2;
+int nonlinearSparseSolverMinSize = 10001;
 double newtonXTol = 1e-12;
 double newtonFTol = 1e-12;
 const size_t SIZERINGBUFFER = 3;

SimulationRuntime/c/simulation/solver/model_help.h

@@ -77,6 +77,8 @@ extern "C" {
 extern int maxEventIterations;
 extern double linearSparseSolverMaxDensity;
 extern int linearSparseSolverMinSize;
+extern double nonlinearSparseSolverMaxDensity;
+extern int nonlinearSparseSolverMinSize;
 extern double newtonXTol;
 extern double newtonFTol;
 extern const size_t SIZERINGBUFFER;

SimulationRuntime/c/simulation/solver/nonlinearSystem.c

@@ -46,6 +46,7 @@
 #include "nonlinearSolverHomotopy.h"
 #include "simulation/simulation_info_json.h"
 #include "simulation/simulation_runtime.h"
+#include "simulation/solver/model_help.h"
 
 /* for try and catch simulationJumpBuffer */
 #include "meta/meta_modelica.h"
@@ -338,7 +339,7 @@ int initializeNonlinearSystems(DATA *data, threadData_t *threadData)
 {
   TRACE_PUSH
   int i,j;
-  int size;
+  int size, nnz;
   NONLINEAR_SYSTEM_DATA *nonlinsys = data->simulationInfo->nonlinearSystemData;
   struct dataNewtonAndHybrid *mixedSolverData;
 
@@ -363,6 +364,19 @@ int initializeNonlinearSystems(DATA *data, threadData_t *threadData)
       }
     }
 
+#if !defined(OMC_MINIMAL_RUNTIME)
+    if (nonlinsys[i].isPatternAvailable)
+    {
+      nnz = nonlinsys[i].sparsePattern.numberOfNoneZeros;
+
+      if(nnz/(double)(size*size)<=nonlinearSparseSolverMaxDensity && size >= nonlinearSparseSolverMinSize)
+      {
+        data->simulationInfo->nlsMethod = NLS_KINSOL;
+        infoStreamPrint(LOG_STDOUT, 0, "Using sparse solver kinsol for nonlinear system %d,\nbecause density of %.2f remains under threshold of %.2f and size of %d exceeds threshold of %d.\nThe maximum density and the minimal system size for using sparse solvers can be specified\nusing the runtime flags '<-nlsMaxDensity=value>' and '<-nlsMinSize=value>'.", i, nnz/(double)(size*size), nonlinearSparseSolverMaxDensity, size, nonlinearSparseSolverMinSize);
+      }
+    }
+#endif
+
     /* allocate system data */
     nonlinsys[i].nlsx = (double*) malloc(size*sizeof(double));
     nonlinsys[i].nlsxExtrapolation = (double*) malloc(size*sizeof(double));
@@ -394,6 +408,7 @@ int initializeNonlinearSystems(DATA *data, threadData_t *threadData)
       }
     }
 #endif
+
     /* allocate solver data */
     switch(data->simulationInfo->nlsMethod)
     {

SimulationRuntime/c/simulation_data.h

@@ -269,7 +269,7 @@ typedef struct NONLINEAR_SYSTEM_DATA
   int (*initialAnalyticalJacobian)(void*, threadData_t*);
   modelica_integer jacobianIndex;
 
-  SPARSE_PATTERN sparsePattern;       /* sparse pattern if no jacobian is available */
+  SPARSE_PATTERN sparsePattern;        /* sparse pattern if no jacobian is available */
   modelica_boolean isPatternAvailable;
 
   void (*residualFunc)(void**, const double*, double*, const int*);
@@ -289,15 +289,15 @@ typedef struct NONLINEAR_SYSTEM_DATA
 
   modelica_real residualError;         /* not used */
   modelica_boolean solved;             /* 1: solved in current step - else not */
-  modelica_real lastTimeSolved;         /* save last successful solved point in time */
+  modelica_real lastTimeSolved;        /* save last successful solved point in time */
 
   /* statistics */
-  unsigned long numberOfCall;           /* number of solving calls of this system */
-  unsigned long numberOfFEval;          /* number of function evaluations of this system */
-  unsigned long numberOfIterations;     /* number of iteration of non-linear solvers of this system */
-  double totalTime;                     /* save the totalTime */
-  rtclock_t totalTimeClock;             /* time clock for the totalTime  */
-  void* csvData;                        /* information to save csv data */
+  unsigned long numberOfCall;          /* number of solving calls of this system */
+  unsigned long numberOfFEval;         /* number of function evaluations of this system */
+  unsigned long numberOfIterations;    /* number of iteration of non-linear solvers of this system */
+  double totalTime;                    /* save the totalTime */
+  rtclock_t totalTimeClock;            /* time clock for the totalTime  */
+  void* csvData;                       /* information to save csv data */
 } NONLINEAR_SYSTEM_DATA;
 #else
 typedef void* NONLINEAR_SYSTEM_DATA;

SimulationRuntime/c/util/simulation_options.c

@@ -85,6 +85,8 @@ const char *FLAG_NAME[FLAG_MAX+1] = {
   /* FLAG_NEWTON_STRATEGY */       "newton",
   /* FLAG_NLS */                   "nls",
   /* FLAG_NLS_INFO */              "nlsInfo",
+  /* FLAG_NLS_MAX_DENSITY */       "nlssMaxDensity",
+  /* FLAG_NLS_MIN_SIZE */          "nlssMinSize",
   /* FLAG_NLS_LS */                "nlsLS",
   /* FLAG_NOEMIT */                "noemit",
   /* FLAG_NOEQUIDISTANT_GRID */    "noEquidistantTimeGrid",
@@ -166,6 +168,8 @@ const char *FLAG_DESC[FLAG_MAX+1] = {
   /* FLAG_NEWTON_STRATEGY */       "value specifies the damping strategy for the newton solver",
   /* FLAG_NLS */                   "value specifies the nonlinear solver",
   /* FLAG_NLS_INFO */              "outputs detailed information about solving process of non-linear systems into csv files.",
+  /* FLAG_NLS_MAX_DENSITY */       "[double (default 0.2)] value specifies the maximum density for using a non-linear sparse solver",
+  /* FLAG_NLS_MIN_SIZE */          "[int (default 10001)] value specifies the minimum system size for using a non-linear sparse solver",
   /* FLAG_NLS_LS */                "value specifies the linear solver used by the non-linear solver",
   /* FLAG_NOEMIT */                "do not emit any results to the result file",
   /* FLAG_NOEQUIDISTANT_GRID */    "stores results not in equidistant time grid as given by stepSize or numberOfIntervals, instead the variable step size of dassl is used.",
@@ -337,6 +341,12 @@ const char *FLAG_DETAILED_DESC[FLAG_MAX+1] = {
   "  * kinsol\n"
   "  * newton\n"
   "  * mixed",
+  /* FLAG_NLS_MAX_DENSITY */
+  "  Value specifies the maximum density for using a non-linear sparse solver.\n"
+  "  The value is a Double with default value 0.2.",
+  /* FLAG_NLS_MIN_SIZE */
+  "  Value specifies the minimum system size for using a non-linear sparse solver.\n"
+  "  The value is an Integer with default value 10001.",
   /* FLAG_NLS_INFO */
   "  Outputs detailed information about solving process of non-linear systems into csv files.",
   /* FLAG_NLS_LS */
@@ -457,6 +467,8 @@ const int FLAG_TYPE[FLAG_MAX] = {
   /* FLAG_NEWTON_XTOL */           FLAG_TYPE_OPTION,
   /* FLAG_NEWTON_STRATEGY */       FLAG_TYPE_OPTION,
   /* FLAG_NLS */                   FLAG_TYPE_OPTION,
+  /* FLAG_NLS_MAX_DENSITY */       FLAG_TYPE_OPTION,
+  /* FLAG_NLS_MIN_SIZE */          FLAG_TYPE_OPTION,
   /* FLAG_NLS_INFO */              FLAG_TYPE_FLAG,
   /* FLAG_NLS_LS */                FLAG_TYPE_OPTION,
   /* FLAG_NOEMIT */                FLAG_TYPE_FLAG,

SimulationRuntime/c/util/simulation_options.h

@@ -92,6 +92,8 @@ enum _FLAG
   FLAG_NEWTON_XTOL,
   FLAG_NEWTON_STRATEGY,
   FLAG_NLS,
+  FLAG_NLS_MAX_DENSITY,
+  FLAG_NLS_MIN_SIZE,
   FLAG_NLS_INFO,
   FLAG_NLS_LS,
   FLAG_NOEMIT,