void polymodel(void)
{
gsl_interp_accel *pmsplacc = gsl_interp_accel_alloc();
bodyptr p;
real rad, phi, vel, psi, vr, vp, a, E, J;
vector rhat, vtmp, vper;
for (p = btab; p < NthBody(btab, nbody); p = NextBody(p)) {
rad = rad_m(xrandom(0.0, mtot));
phi = gsl_spline_eval(pmspline, (double) rad, pmsplacc);
vel = pick_v(phi);
psi = pick_psi();
vr = vel * rcos(psi);
vp = vel * rsin(psi);
Mass(p) = mtot / nbody;
pickshell(rhat, NDIM, 1.0);
MULVS(Pos(p), rhat, rad);
pickshell(vtmp, NDIM, 1.0);
a = dotvp(vtmp, rhat);
MULVS(vper, rhat, - a);
ADDV(vper, vper, vtmp);
a = absv(vper);
MULVS(vper, vper, vp / a);
MULVS(Vel(p), rhat, vr);
ADDV(Vel(p), Vel(p), vper);
Phi(p) = phi;
E = phi + 0.5 * rsqr(vel);
J = rad * ABS(vp);
Aux(p) = Kprime * rpow(phi1 - E, npol - 1.5) * rpow(J, 2 * mpol);
}
gsl_interp_accel_free(pmsplacc);
}
local void testdata(void) {
real rsc, vsc, r, v, x, y;
bodyptr p;
float scale = 1.0f;
float vscale = 1.0f;
float mscale = 1.0f;
if (nbody < 1) // check for silly values
error("%s: absurd value for nbody\n", getargv0());
bodytab = (bodyptr) allocate(nbody * sizeof(body));
// alloc space for bodies
rsc = (3 * PI) / 16; // set length scale factor
vsc = rsqrt(1.0 / rsc); // find speed scale factor
for (p = bodytab; p < bodytab+nbody; p++) { // loop over particles
Type(p) = BODY; // tag as a body
//Mass(p) = 1.0 / nbody; // set masses equal
// Set mass randomly, like in brute
Mass(p) = (rand() / (float) RAND_MAX) * mscale;
x = xrandom(0.0, MFRAC); // pick enclosed mass
r = 1.0 / rsqrt(rpow(x, -2.0/3.0) - 1); // find enclosing radius
pickshell(Pos(p), NDIM, rsc * r); // pick position vector
do { // select from fn g(x)
x = xrandom(0.0, 1.0); // for x in range 0:1
y = xrandom(0.0, 0.1); // max of g(x) is 0.092
} while (y > x*x * rpow(1 - x*x, 3.5)); // using von Neumann tech
v = x * rsqrt(2.0 / rsqrt(1 + r*r)); // find resulting speed
pickshell(Vel(p), NDIM, vsc * v); // pick velocity vector
}
tnow = 0.0; // set elapsed model time
}
void picktriad(vector x, vector y, vector z)
{
real a;
pickshell(x, NDIM, 1.0);
pickshell(z, NDIM, 1.0);
CROSSVP(y, x, z);
a = absv(y);
DIVVS(y, y, a);
CROSSVP(z, x, y);
}
void makedisk(bool randspin)
{
int i;
bodyptr bp;
double m, r, v, phi;
matrix xmat, zmat;
vector tmpv;
for (i = 0; i < ndisk; i++) { // loop initializing bodies
bp = NthBody(disk, i); // set ptr to body number i
m = mdtab[NTAB-1] * ((double) i + 0.5) / ndisk;
r = gsl_interp_eval(rm_spline, mdtab, rdtab, m, NULL);
v = gsl_interp_eval(vr_spline, rdtab, vctab, r, NULL);
phi = xrandom(0.0, 2 * M_PI);
Pos(bp)[0] = r * sin(phi);
Pos(bp)[1] = r * cos(phi);
Pos(bp)[2] = 0.0;
Vel(bp)[0] = v * cos(phi);
Vel(bp)[1] = - v * sin(phi);
Vel(bp)[2] = 0.0;
pickshell(AuxVec(bp), NDIM, 1.0);
if (randspin) {
xmatrix(xmat, acos(AuxVec(bp)[2]));
zmatrix(zmat, atan2(AuxVec(bp)[0], AuxVec(bp)[1]));
MULMV(tmpv, xmat, Pos(bp));
MULMV(Pos(bp), zmat, tmpv);
MULMV(tmpv, xmat, Vel(bp));
MULMV(Vel(bp), zmat, tmpv);
}
}
}
void gspsphere(void)
{
real gamma0, mcut, r, sig2, eint = 0.0;
static real *sig2tab = NULL;
bodyptr bp;
nbody = getiparam("nbody");
assert(nbody > 0);
gamma0 = getdparam("gamma");
mcut = getdparam("mcut");
assert(0.0 < mcut && mcut <= 1.0);
if (sig2tab == NULL)
sig2tab = calc_sig2_gsp(gsp, ggsp, 0.0);
if (btab == NULL)
btab = (bodyptr) allocate(nbody * SizeofBody);
for (bp = btab; bp < NthBody(btab, nbody); bp = NextBody(bp)) {
Mass(bp) = gsp->mtot / nbody;
r = r_mass_gsp(gsp, xrandom(0.0, mcut * gsp->mtot));
pickshell(Pos(bp), NDIM, r);
CLRV(Vel(bp));
Rho(bp) = rho_gsp(gsp, r);
sig2 = sig2_gsp(gsp, ggsp, 0.0, sig2tab, r);
EntFunc(bp) = sig2 / rpow(Rho(bp), gamma0 - 1);
Uintern(bp) = sig2 / (gamma0 - 1);
eint += Mass(bp) * Uintern(bp);
}
eprintf("[%s: thermal energy = %f]\n", getargv0(), eint);
}
void pickvec(vector x, bool cf)
{
dprintf(1,"pickvec: cf = %d\t", cf);
if (cf) /* cent. concentrated? */
pickshell(x, NDIM, xrandom(0.0, 1.0)); /* pick from M(r) = r */
else
pickball(x, NDIM, 1.0); /* use uniform distr. */
dprintf(1,"x = [%8.4f,%8.4f,%8.4f]\n", x[0], x[1], x[2]);
}
void plummodel(real mfrac)
{
real rsc, vsc, r, v, x, y;
bodyptr p;
if (mfrac < 0 || mfrac > 1) // check for silly values
error("%s: absurd value for mfrac\n", getprog());
rsc = (3 * PI) / 16; // set length scale factor
vsc = rsqrt(1.0 / rsc); // and speed scale factor
for (p = btab; p < NthBody(btab,nbody); p = NextBody(p)) {
// loop over particles
Mass(p) = 1.0 / nbody; // set masses equal
x = xrandom(0.0, mfrac); // pick enclosed mass
r = 1.0 / rsqrt(rpow(x, -2.0/3.0) - 1); // find enclosing radius
pickshell(Pos(p), NDIM, rsc * r); // pick position vector
do { // use von Neumann rejection
x = xrandom(0.0, 1.0); // for x in range 0:1
y = xrandom(0.0, 0.1); // max of g(x) is 0.092
} while (y > x*x * rpow(1 - x*x, 3.5)); // select from g(x)
v = x * rsqrt(2.0 / rsqrt(1 + r*r)); // find resulting speed
pickshell(Vel(p), NDIM, vsc * v); // pick velocity vector
Phi(p) = -1.0 / (rsc * rsqrt(rsqr(r) + 1)); // compute model potential
}
}
void polymodel1(void)
{
bodyptr p;
real r, x, v;
for (p = btab; p < NthBody(btab, nbody); p = NextBody(p)) {
Mass(p) = 1.0 / nbody;
r = xrandom(0.0, 2.0);
pickshell(Pos(p), 3, r);
x = SQRT2 * rcos(PI * (2.0 - xrandom(0.0, 1.0)) / 4.0);
v = (xrandom(-1.0, 1.0) < 0.0 ? -1.0 : 1.0) *
(1 - x*x) * rsqrt(rlog(2 / r));
MULVS(Vel(p), Pos(p), v/r);
Phi(p) = 0.5 * rlog(r / 2.0) - 0.5;
}
bodyfields[4] = NULL; // don't output Aux data
}
