more updates -> testing
[physik/posic.git] / moldyn.c
index 505f496..eb2c606 100644 (file)
--- a/moldyn.c
+++ b/moldyn.c
@@ -41,6 +41,7 @@ int moldyn_init(t_moldyn *moldyn,int argc,char **argv) {
 
 int moldyn_shutdown(t_moldyn *moldyn) {
 
+       moldyn_log_shutdown(moldyn);
        link_cell_shutdown(moldyn);
        moldyn_log_shutdown(moldyn);
        rand_close(&(moldyn->random));
@@ -251,11 +252,12 @@ int add_atom(t_moldyn *moldyn,int element,double mass,u8 bnum,u8 attr,
        moldyn->atom=ptr;
 
        atom=moldyn->atom;
-       atom->r=*r;
-       atom->v=*v;
-       atom->element=element;
-       atom->bnum=bnum;
-       atom->attr=attr;
+       atom[count-1].r=*r;
+       atom[count-1].v=*v;
+       atom[count-1].element=element;
+       atom[count-1].mass=mass;
+       atom[count-1].bnum=bnum;
+       atom[count-1].attr=attr;
 
        return 0;
 }
@@ -326,6 +328,12 @@ int scale_velocity(t_moldyn *moldyn) {
        /*
         * - velocity scaling (E = 3/2 N k T), E: kinetic energy
         */
+
+       if(moldyn->t==0.0) {
+               printf("[moldyn] no velocity scaling for T = 0 K\n");
+               return -1;
+       }
+
        e=0.0;
        for(i=0;i<moldyn->count;i++)
                e+=0.5*atom[i].mass*v3_absolute_square(&(atom[i].v));
@@ -382,15 +390,19 @@ t_3dvec get_total_p(t_moldyn *moldyn) {
        return p_total;
 }
 
-double estimate_time_step(t_moldyn *moldyn,double nn_dist,double t) {
+double estimate_time_step(t_moldyn *moldyn,double nn_dist) {
 
        double tau;
 
-       tau=0.05*nn_dist/(sqrt(3.0*K_BOLTZMANN*t/moldyn->atom[0].mass));
-       tau*=1.0E-9;
-       if(tau<moldyn->tau)
-               printf("[moldyn] warning: time step  (%f > %.15f)\n",
-                      moldyn->tau,tau);
+       /* nn_dist is the nearest neighbour distance */
+
+       if(moldyn->t==5.0) {
+               printf("[moldyn] i do not estimate timesteps below %f K!\n",
+                      MOLDYN_CRITICAL_EST_TEMP);
+               return 23.42;
+       }
+
+       tau=(0.05*nn_dist*moldyn->atom[0].mass)/sqrt(3.0*K_BOLTZMANN*moldyn->t);
 
        return tau;     
 }
@@ -582,11 +594,13 @@ int moldyn_integrate(t_moldyn *moldyn) {
        unsigned int e,m,s,v;
        t_3dvec p;
        t_moldyn_schedule *schedule;
+       t_atom *atom;
 
        int fd;
        char fb[128];
 
        schedule=&(moldyn->schedule);
+       atom=moldyn->atom;
 
        /* initialize linked cell method */
        link_cell_init(moldyn);
@@ -695,7 +709,7 @@ int velocity_verlet(t_moldyn *moldyn) {
                v3_add(&(atom[i].r),&(atom[i].r),&delta);
                v3_scale(&delta,&(atom[i].f),0.5*tau_square/atom[i].mass);
                v3_add(&(atom[i].r),&(atom[i].r),&delta);
-               v3_per_bound(&(atom[i].r),&(moldyn->dim));
+               check_per_bound(moldyn,&(atom[i].r));
 
                /* velocities */
                v3_scale(&delta,&(atom[i].f),0.5*tau/atom[i].mass);
@@ -755,7 +769,7 @@ int potential_force_calc(t_moldyn *moldyn) {
 
                /* 2 body pair potential/force */
                if(atom[i].attr&(ATOM_ATTR_2BP|ATOM_ATTR_3BP)) {
-               
+       
                        link_cell_neighbour_index(moldyn,
                                (atom[i].r.x+moldyn->dim.x/2)/lc->x,
                                (atom[i].r.y+moldyn->dim.y/2)/lc->y,
@@ -889,7 +903,6 @@ int harmonic_oscillator(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 
        v3_sub(&distance,&(ai->r),&(aj->r));
        
-       v3_per_bound(&distance,&(moldyn->dim));
        if(bc) check_per_bound(moldyn,&distance);
        d=v3_norm(&distance);
        if(d<=moldyn->cutoff) {
@@ -933,7 +946,7 @@ int lennard_jones(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
                d=+h1-h2;
                d*=eps;
                v3_scale(&force,&distance,d);
-               v3_add(&(ai->f),&(aj->f),&force);
+               v3_add(&(ai->f),&(ai->f),&force);
        }
 
        return 0;