Add EAM force field

Signed-off-by: Rafael Ravedutti <rafaelravedutti@gmail.com>

src/main.c

@@ -39,13 +39,17 @@
 #include <thermo.h>
 #include <pbc.h>
 #include <timers.h>
+#include <eam.h>
 
 #define HLINE "----------------------------------------------------------------------------\n"
 
 extern double computeForce(Parameter*, Atom*, Neighbor*, Stats*, int, int);
+extern double computeForceEam(Eam* eam, Atom *atom, Neighbor *neighbor, Stats *stats, int first_exec, int timestep);
 
 void init(Parameter *param)
 {
+    param->input_file = NULL;
+    param->force_field = FF_LJ;
     param->epsilon = 1.0;
     param->sigma6 = 1.0;
     param->rho = 0.8442;
@@ -67,6 +71,7 @@ void init(Parameter *param)
 
 double setup(
         Parameter *param,
+        Eam *eam,
         Atom *atom,
         Neighbor *neighbor,
         Stats *stats)
@@ -78,6 +83,7 @@ double setup(
     param->zprd = param->nz * param->lattice;
 
     S = getTimeStamp();
+    if(param->force_field == FF_EAM) { initEam(eam, param->input_file, param->ntypes); }
     initAtom(atom);
     initNeighbor(neighbor, param);
     initPbc();
@@ -153,9 +159,24 @@ void printAtomState(Atom *atom)
 /*     } */
 }
 
-int main (int argc, char** argv)
+int str2ff(const char *string)
+{
+    if(strncmp(string, "lj", 2) == 0) return FF_LJ;
+    if(strncmp(string, "eam", 3) == 0) return FF_EAM;
+    return -1;
+}
+
+const char* ff2str(int ff)
+{
+    if(ff == FF_LJ) { return "lj"; }
+    if(ff == FF_EAM) { return "eam"; }
+    return "invalid";
+}
+
+int main(int argc, char** argv)
 {
     double timer[NUMTIMER];
+    Eam eam;
     Atom atom;
     Neighbor neighbor;
     Stats stats;
@@ -172,6 +193,19 @@ int main (int argc, char** argv)
 
     for(int i = 0; i < argc; i++)
     {
+        if((strcmp(argv[i], "-f") == 0))
+        {
+            if((param.force_field = str2ff(argv[++i])) < 0) {
+                fprintf(stderr, "Invalid force field!\n");
+                exit(-1);
+            }
+            continue;
+        }
+        if((strcmp(argv[i], "-i") == 0))
+        {
+            param.input_file = strdup(argv[++i]);
+            continue;
+        }
         if((strcmp(argv[i], "-n") == 0) || (strcmp(argv[i], "--nsteps") == 0))
         {
             param.ntimes = atoi(argv[++i]);
@@ -192,7 +226,7 @@ int main (int argc, char** argv)
             param.nz = atoi(argv[++i]);
             continue;
         }
-        if((strcmp(argv[i], "-f") == 0))
+        if((strcmp(argv[i], "--freq") == 0))
         {
             param.proc_freq = atof(argv[++i]);
             continue;
@@ -201,17 +235,24 @@ int main (int argc, char** argv)
         {
             printf("MD Bench: A minimalistic re-implementation of miniMD\n");
             printf(HLINE);
+            printf("-f <string>:          force field (lj or eam), default lj\n");
+            printf("-i <string>:          input file for EAM\n");
             printf("-n / --nsteps <int>:  set number of timesteps for simulation\n");
             printf("-nx/-ny/-nz <int>:    set linear dimension of systembox in x/y/z direction\n");
-            printf("-f <real>:            processor frequency (GHz)\n");
+            printf("--freq <real>:        processor frequency (GHz)\n");
             printf(HLINE);
             exit(EXIT_SUCCESS);
         }
     }
 
-    setup(&param, &atom, &neighbor, &stats);
+    setup(&param, &eam, &atom, &neighbor, &stats);
     computeThermo(0, &param, &atom);
-    computeForce(&param, &atom, &neighbor, &stats, 1, 0);
+
+    if(param.force_field == FF_EAM) {
+        computeForceEam(&eam, &atom, &neighbor, &stats, 1, 0);
+    } else {
+        computeForce(&param, &atom, &neighbor, &stats, 1, 0);
+    }
 
     timer[FORCE] = 0.0;
     timer[NEIGH] = 0.0;
@@ -226,7 +267,12 @@ int main (int argc, char** argv)
             timer[NEIGH] += reneighbour(&param, &atom, &neighbor);
         }
 
-        timer[FORCE] += computeForce(&param, &atom, &neighbor, &stats, 0, n + 1);
+        if(param.force_field == FF_EAM) {
+            timer[FORCE] += computeForceEam(&eam, &atom, &neighbor, &stats, 0, n + 1);
+        } else {
+            timer[FORCE] += computeForce(&param, &atom, &neighbor, &stats, 0, n + 1);
+        }
+
         finalIntegrate(&param, &atom);
 
         if(!((n + 1) % param.nstat) && (n+1) < param.ntimes) {
@@ -238,6 +284,7 @@ int main (int argc, char** argv)
     computeThermo(-1, &param, &atom);
 
     printf(HLINE);
+    printf("Force field: %s\n", ff2str(param.force_field));
     printf("Data layout for positions: %s\n", POS_DATA_LAYOUT);
 #if PRECISION == 1
     printf("Using single precision floating point.\n");