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40 static char *SRCID_random_h = "$Id$";
46 #ident "@(#) random.h 1.5 12/16/92"
47 #endif /* HAVE_IDENT */
51 extern real gauss(real am, real sd, int *ig);
52 /* Generate a gaussian number with:
53 * am = center of the distribution
54 * sd = standard deviation
55 * ig = the random number seed.
58 extern int make_seed(void);
59 /* Make a random seed: (time+getpid) % 1000000 */
61 extern real rando(int *ig);
62 /* Generate a random number 0 <= r < 1. ig is the (address of) the
66 extern void grp_maxwell(t_block *grp,real tempi[],int nrdf[],int seed,
67 t_atoms *atoms,rvec v[]);
68 /* Generate for each group in grp a temperature.
69 * When seed = -1, set the seed to make_seed.
72 extern void maxwell_speed(real tempi,int nrdf,int seed,
73 t_atoms *atoms, rvec v[]);
74 /* Generate velocites according to a maxwellian distribution */
76 extern real calc_cm(FILE *log,int natoms,real mass[],rvec x[],rvec v[],
77 rvec xcm,rvec vcm,rvec acm,matrix L);
78 /* Calculate the c.o.m. position, velocity, acceleration and the
79 * moment of Inertia. Returns the total mass.
82 extern void stop_cm(FILE *log,int natoms,real mass[],rvec x[],rvec v[]);
84 #endif /* _random_h */