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Commit da18a66d authored by Matthieu Schaller's avatar Matthieu Schaller
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Move rho_dh into the density sub-structure. Update the pressure and... 

Move rho_dh into the density sub-structure. Update the pressure and sound-speed after kick and drift
parent 5c46ced3
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1 merge request!255Cleanup rho dh and use of the EoS functions
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with 102 additions and 68 deletions
src/const.h
+ 4
− 4
View file @ da18a66d
......@@ -40,8 +40,8 @@
#define const_isothermal_internal_energy 20.2615290634f
/* Dimensionality of the problem */
#define HYDRO_DIMENSION_3D
//#define HYDRO_DIMENSION_2D
//#define HYDRO_DIMENSION_3D
#define HYDRO_DIMENSION_2D
//#define HYDRO_DIMENSION_1D
/* Hydrodynamical adiabatic index. */
......@@ -63,8 +63,8 @@
//#define WENDLAND_C6_KERNEL
/* SPH variant to use */
//#define MINIMAL_SPH
#define GADGET2_SPH
#define MINIMAL_SPH
//#define GADGET2_SPH
//#define HOPKINS_PE_SPH
//#define DEFAULT_SPH
//#define GIZMO_SPH
......
src/hydro/Gadget2/hydro.h
+ 30
− 8
View file @ da18a66d
......@@ -195,7 +195,7 @@ __attribute__((always_inline)) INLINE static void hydro_init_part(
p->density.wcount = 0.f;
p->density.wcount_dh = 0.f;
p->rho = 0.f;
p->rho_dh = 0.f;
p->density.rho_dh = 0.f;
p->density.div_v = 0.f;
p->density.rot_v[0] = 0.f;
p->density.rot_v[1] = 0.f;
......@@ -222,20 +222,17 @@ __attribute__((always_inline)) INLINE static void hydro_end_density(
/* Final operation on the density (add self-contribution). */
p->rho += p->mass * kernel_root;
p->rho_dh -= hydro_dimension * p->mass * kernel_root;
p->density.rho_dh -= hydro_dimension * p->mass * kernel_root;
p->density.wcount += kernel_root;
/* Finish the calculation by inserting the missing h-factors */
p->rho *= h_inv_dim;
p->rho_dh *= h_inv_dim_plus_one;
p->density.rho_dh *= h_inv_dim_plus_one;
p->density.wcount *= kernel_norm;
p->density.wcount_dh *= h_inv * kernel_gamma * kernel_norm;
const float rho_inv = 1.f / p->rho;
/* Compute the derivative term */
p->rho_dh = 1.f / (1.f + hydro_dimension_inv * p->h * p->rho_dh * rho_inv);
/* Finish calculation of the velocity curl components */
p->density.rot_v[0] *= h_inv_dim_plus_one * rho_inv;
p->density.rot_v[1] *= h_inv_dim_plus_one * rho_inv;
......@@ -276,7 +273,7 @@ __attribute__((always_inline)) INLINE static void hydro_prepare_force(
const float rho_inv = 1.f / p->rho;
/* Divide the pressure by the density and density gradient */
const float P_over_rho2 = pressure * rho_inv * rho_inv * p->rho_dh;
const float P_over_rho2 = pressure * rho_inv * rho_inv;
/* Compute the sound speed */
const float soundspeed = sqrtf(hydro_gamma * pressure * rho_inv);
......@@ -285,7 +282,12 @@ __attribute__((always_inline)) INLINE static void hydro_prepare_force(
const float balsara =
abs_div_v / (abs_div_v + curl_v + 0.0001f * soundspeed / fac_mu / p->h);
/* Compute the "grad h" term */
const float grad_h_term =
1.f / (1.f + hydro_dimension_inv * p->h * p->density.rho_dh * rho_inv);
/* Update variables. */
p->force.f = grad_h_term;
p->force.P_over_rho2 = P_over_rho2;
p->force.soundspeed = soundspeed;
p->force.balsara = balsara;
......@@ -352,7 +354,7 @@ __attribute__((always_inline)) INLINE static void hydro_predict_extra(
const float rho_inv = 1.f / p->rho;
/* Divide the pressure by the density and density gradient */
const float P_over_rho2 = pressure * rho_inv * rho_inv * p->rho_dh;
const float P_over_rho2 = pressure * rho_inv * rho_inv;
/* Compute the new sound speed */
const float soundspeed = sqrtf(hydro_gamma * pressure * rho_inv);
......@@ -400,6 +402,16 @@ __attribute__((always_inline)) INLINE static void hydro_kick_extra(
/* Do not 'overcool' when timestep increases */
if (p->entropy + p->entropy_dt * half_dt < 0.5f * p->entropy)
p->entropy_dt = -0.5f * p->entropy / half_dt;
/* Compute the pressure */
const float pressure = gas_pressure_from_entropy(p->rho, p->entropy);
/* Compute the sound speed from the pressure*/
const float rho_inv = 1.f / p->rho;
const float soundspeed = sqrtf(hydro_gamma * pressure * rho_inv);
p->force.soundspeed = soundspeed;
p->force.P_over_rho2 = pressure * rho_inv * rho_inv;
}
/**
......@@ -414,6 +426,16 @@ __attribute__((always_inline)) INLINE static void hydro_convert_quantities(
/* We read u in the entropy field. We now get S from u */
p->entropy = gas_entropy_from_internal_energy(p->rho, p->entropy);
/* Compute the pressure */
const float pressure = gas_pressure_from_entropy(p->rho, p->entropy);
/* Compute the sound speed from the pressure*/
const float rho_inv = 1.f / p->rho;
const float soundspeed = sqrtf(hydro_gamma * pressure * rho_inv);
p->force.soundspeed = soundspeed;
p->force.P_over_rho2 = pressure * rho_inv * rho_inv;
}
#endif /* SWIFT_GADGET2_HYDRO_H */
src/hydro/Gadget2/hydro_debug.h
+ 2
− 2
View file @ da18a66d
......@@ -30,8 +30,8 @@ __attribute__((always_inline)) INLINE static void hydro_debug_particle(
"v_sig=%e dh/dt=%.3e t_begin=%d, t_end=%d\n",
p->x[0], p->x[1], p->x[2], p->v[0], p->v[1], p->v[2], xp->v_full[0],
xp->v_full[1], xp->v_full[2], p->a_hydro[0], p->a_hydro[1], p->a_hydro[2],
p->h, p->density.wcount, p->density.wcount_dh, p->mass, p->rho_dh, p->rho,
hydro_get_pressure(p, 0.), p->force.P_over_rho2, p->entropy,
p->h, p->density.wcount, p->density.wcount_dh, p->mass, p->density.rho_dh,
p->rho, hydro_get_pressure(p, 0.), p->force.P_over_rho2, p->entropy,
p->entropy_dt, p->force.soundspeed, p->density.div_v, p->density.rot_v[0],
p->density.rot_v[1], p->density.rot_v[2], p->force.balsara,
p->force.v_sig, p->force.h_dt, p->ti_begin, p->ti_end);
......
src/hydro/Gadget2/hydro_iact.h
+ 18
− 10
View file @ da18a66d
......@@ -59,7 +59,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
/* Compute contribution to the density */
pi->rho += mj * wi;
pi->rho_dh -= mj * (hydro_dimension * wi + ui * wi_dx);
pi->density.rho_dh -= mj * (hydro_dimension * wi + ui * wi_dx);
/* Compute contribution to the number of neighbours */
pi->density.wcount += wi;
......@@ -72,7 +72,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
/* Compute contribution to the density */
pj->rho += mi * wj;
pj->rho_dh -= mi * (hydro_dimension * wj + uj * wj_dx);
pj->density.rho_dh -= mi * (hydro_dimension * wj + uj * wj_dx);
/* Compute contribution to the number of neighbours */
pj->density.wcount += wj;
......@@ -209,13 +209,13 @@ __attribute__((always_inline)) INLINE static void runner_iact_vec_density(
/* Update particles. */
for (k = 0; k < VEC_SIZE; k++) {
pi[k]->rho += rhoi.f[k];
pi[k]->rho_dh -= rhoi_dh.f[k];
pi[k]->density.rho_dh -= rhoi_dh.f[k];
pi[k]->density.wcount += wcounti.f[k];
pi[k]->density.wcount_dh -= wcounti_dh.f[k];
pi[k]->density.div_v -= div_vi.f[k];
for (j = 0; j < 3; j++) pi[k]->density.rot_v[j] += curl_vi[j].f[k];
pj[k]->rho += rhoj.f[k];
pj[k]->rho_dh -= rhoj_dh.f[k];
pj[k]->density.rho_dh -= rhoj_dh.f[k];
pj[k]->density.wcount += wcountj.f[k];
pj[k]->density.wcount_dh -= wcountj_dh.f[k];
pj[k]->density.div_v -= div_vj.f[k];
......@@ -254,7 +254,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_density(
/* Compute contribution to the density */
pi->rho += mj * wi;
pi->rho_dh -= mj * (hydro_dimension * wi + ui * wi_dx);
pi->density.rho_dh -= mj * (hydro_dimension * wi + ui * wi_dx);
/* Compute contribution to the number of neighbours */
pi->density.wcount += wi;
......@@ -366,7 +366,7 @@ runner_iact_nonsym_vec_density(float *R2, float *Dx, float *Hi, float *Hj,
/* Update particles. */
for (k = 0; k < VEC_SIZE; k++) {
pi[k]->rho += rhoi.f[k];
pi[k]->rho_dh -= rhoi_dh.f[k];
pi[k]->density.rho_dh -= rhoi_dh.f[k];
pi[k]->density.wcount += wcounti.f[k];
pi[k]->density.wcount_dh -= wcounti_dh.f[k];
pi[k]->density.div_v -= div_vi.f[k];
......@@ -415,7 +415,11 @@ __attribute__((always_inline)) INLINE static void runner_iact_force(
kernel_deval(xj, &wj, &wj_dx);
const float wj_dr = hjd_inv * wj_dx;
/* Compute gradient terms */
/* Compute h-gradient terms */
const float f_i = pi->force.f;
const float f_j = pj->force.f;
/* Compute pressure terms */
const float P_over_rho2_i = pi->force.P_over_rho2;
const float P_over_rho2_j = pj->force.P_over_rho2;
......@@ -447,7 +451,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_force(
/* Now, convolve with the kernel */
const float visc_term = 0.5f * visc * (wi_dr + wj_dr) * r_inv;
const float sph_term =
(P_over_rho2_i * wi_dr + P_over_rho2_j * wj_dr) * r_inv;
(f_i * P_over_rho2_i * wi_dr + f_j * P_over_rho2_j * wj_dr) * r_inv;
/* Eventually got the acceleration */
const float acc = visc_term + sph_term;
......@@ -690,7 +694,11 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_force(
kernel_deval(xj, &wj, &wj_dx);
const float wj_dr = hjd_inv * wj_dx;
/* Compute gradient terms */
/* Compute h-gradient terms */
const float f_i = pi->force.f;
const float f_j = pj->force.f;
/* Compute pressure terms */
const float P_over_rho2_i = pi->force.P_over_rho2;
const float P_over_rho2_j = pj->force.P_over_rho2;
......@@ -722,7 +730,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_force(
/* Now, convolve with the kernel */
const float visc_term = 0.5f * visc * (wi_dr + wj_dr) * r_inv;
const float sph_term =
(P_over_rho2_i * wi_dr + P_over_rho2_j * wj_dr) * r_inv;
(f_i * P_over_rho2_i * wi_dr + f_j * P_over_rho2_j * wj_dr) * r_inv;
/* Eventually got the acceleration */
const float acc = visc_term + sph_term;
......
src/hydro/Gadget2/hydro_part.h
+ 6
− 3
View file @ da18a66d
......@@ -80,9 +80,6 @@ struct part {
/* Entropy time derivative */
float entropy_dt;
/* Derivative of the density with respect to smoothing length. */
float rho_dh;
union {
struct {
......@@ -93,6 +90,9 @@ struct part {
/* Number of neighbours spatial derivative. */
float wcount_dh;
/* Derivative of the density with respect to h. */
float rho_dh;
/* Particle velocity curl. */
float rot_v[3];
......@@ -106,6 +106,9 @@ struct part {
/* Balsara switch */
float balsara;
/*! "Grad h" term */
float f;
/* Pressure over density squared (including drho/dh term) */
float P_over_rho2;
......
src/hydro/Minimal/hydro.h
+ 20
− 9
View file @ da18a66d
......@@ -214,7 +214,7 @@ __attribute__((always_inline)) INLINE static void hydro_init_part(
p->density.wcount = 0.f;
p->density.wcount_dh = 0.f;
p->rho = 0.f;
p->rho_dh = 0.f;
p->density.rho_dh = 0.f;
}
/**
......@@ -240,19 +240,14 @@ __attribute__((always_inline)) INLINE static void hydro_end_density(
/* Final operation on the density (add self-contribution). */
p->rho += p->mass * kernel_root;
p->rho_dh -= hydro_dimension * p->mass * kernel_root;
p->density.rho_dh -= hydro_dimension * p->mass * kernel_root;
p->density.wcount += kernel_root;
/* Finish the calculation by inserting the missing h-factors */
p->rho *= h_inv_dim;
p->rho_dh *= h_inv_dim_plus_one;
p->density.rho_dh *= h_inv_dim_plus_one;
p->density.wcount *= kernel_norm;
p->density.wcount_dh *= h_inv * kernel_gamma * kernel_norm;
const float irho = 1.f / p->rho;
/* Compute the derivative term */
p->rho_dh = 1.f / (1.f + hydro_dimension_inv * p->h * p->rho_dh * irho);
}
/**
......@@ -276,7 +271,14 @@ __attribute__((always_inline)) INLINE static void hydro_prepare_force(
const float half_dt = (ti_current - (p->ti_begin + p->ti_end) / 2) * timeBase;
const float pressure = hydro_get_pressure(p, half_dt);
const float rho_inv = 1.f / p->rho;
/* Compute the "grad h" term */
const float grad_h_term =
1.f / (1.f + hydro_dimension_inv * p->h * p->density.rho_dh * rho_inv);
/* Update variables. */
p->force.f = grad_h_term;
p->force.pressure = pressure;
}
......@@ -379,6 +381,10 @@ __attribute__((always_inline)) INLINE static void hydro_kick_extra(
/* Do not 'overcool' when timestep increases */
if (p->u + p->u_dt * half_dt < 0.5f * p->u) p->u_dt = -0.5f * p->u / half_dt;
/* Compute the pressure */
const float pressure = gas_pressure_from_internal_energy(p->rho, p->u);
p->force.pressure = pressure;
}
/**
......@@ -392,6 +398,11 @@ __attribute__((always_inline)) INLINE static void hydro_kick_extra(
* @param p The particle to act upon
*/
__attribute__((always_inline)) INLINE static void hydro_convert_quantities(
struct part *restrict p) {}
struct part *restrict p) {
/* Compute the pressure */
const float pressure = gas_pressure_from_internal_energy(p->rho, p->u);
p->force.pressure = pressure;
}
#endif /* SWIFT_MINIMAL_HYDRO_H */
src/hydro/Minimal/hydro_debug.h
+ 1
− 1
View file @ da18a66d
......@@ -44,7 +44,7 @@ __attribute__((always_inline)) INLINE static void hydro_debug_particle(
p->x[0], p->x[1], p->x[2], p->v[0], p->v[1], p->v[2], xp->v_full[0],
xp->v_full[1], xp->v_full[2], p->a_hydro[0], p->a_hydro[1], p->a_hydro[2],
p->u, p->u_dt, p->force.v_sig, p->force.pressure, p->h, p->force.h_dt,
(int)p->density.wcount, p->mass, p->rho_dh, p->rho, p->ti_begin,
(int)p->density.wcount, p->mass, p->density.rho_dh, p->rho, p->ti_begin,
p->ti_end);
}
......
src/hydro/Minimal/hydro_iact.h
+ 7
− 7
View file @ da18a66d
......@@ -55,7 +55,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
kernel_deval(xi, &wi, &wi_dx);
pi->rho += mj * wi;
pi->rho_dh -= mj * (hydro_dimension * wi + xi * wi_dx);
pi->density.rho_dh -= mj * (hydro_dimension * wi + xi * wi_dx);
pi->density.wcount += wi;
pi->density.wcount_dh -= xi * wi_dx;
......@@ -65,7 +65,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
kernel_deval(xj, &wj, &wj_dx);
pj->rho += mi * wj;
pj->rho_dh -= mi * (hydro_dimension * wj + xj * wj_dx);
pj->density.rho_dh -= mi * (hydro_dimension * wj + xj * wj_dx);
pj->density.wcount += wj;
pj->density.wcount_dh -= xj * wj_dx;
}
......@@ -100,7 +100,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_density(
kernel_deval(xi, &wi, &wi_dx);
pi->rho += mj * wi;
pi->rho_dh -= mj * (hydro_dimension * wi + xi * wi_dx);
pi->density.rho_dh -= mj * (hydro_dimension * wi + xi * wi_dx);
pi->density.wcount += wi;
pi->density.wcount_dh -= xi * wi_dx;
}
......@@ -152,8 +152,8 @@ __attribute__((always_inline)) INLINE static void runner_iact_force(
const float wj_dr = hjd_inv * wj_dx;
/* Compute gradient terms */
const float P_over_rho2_i = pressurei / (rhoi * rhoi) * pi->rho_dh;
const float P_over_rho2_j = pressurej / (rhoj * rhoj) * pj->rho_dh;
const float P_over_rho2_i = pressurei / (rhoi * rhoi) * pi->force.f;
const float P_over_rho2_j = pressurej / (rhoj * rhoj) * pj->force.f;
/* Compute dv dot r. */
const float dvdr = (pi->v[0] - pj->v[0]) * dx[0] +
......@@ -263,8 +263,8 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_force(
const float wj_dr = hjd_inv * wj_dx;
/* Compute gradient terms */
const float P_over_rho2_i = pressurei / (rhoi * rhoi) * pi->rho_dh;
const float P_over_rho2_j = pressurej / (rhoj * rhoj) * pj->rho_dh;
const float P_over_rho2_i = pressurei / (rhoi * rhoi) * pi->force.f;
const float P_over_rho2_j = pressurej / (rhoj * rhoj) * pj->force.f;
/* Compute dv dot r. */
const float dvdr = (pi->v[0] - pj->v[0]) * dx[0] +
......
src/hydro/Minimal/hydro_part.h
+ 6
− 3
View file @ da18a66d
......@@ -93,9 +93,6 @@ struct part {
/*! Particle density. */
float rho;
/*! Derivative of density with respect to h */
float rho_dh;
/* Store density/force specific stuff. */
union {
......@@ -114,6 +111,9 @@ struct part {
/*! Derivative of the neighbour number with respect to h. */
float wcount_dh;
/*! Derivative of density with respect to h */
float rho_dh;
} density;
/**
......@@ -125,6 +125,9 @@ struct part {
*/
struct {
/*! "Grad h" term */
float f;
/*! Particle pressure. */
float pressure;
......
tests/test27cells.c
+ 2
− 6
View file @ da18a66d
......@@ -199,10 +199,8 @@ void dump_particle_fields(char *fileName, struct cell *main_cell,
hydro_get_density(&main_cell->parts[pid]),
#if defined(GIZMO_SPH)
0.f,
#elif defined(HOPKINS_PE_SPH)
main_cell->parts[pid].density.rho_dh,
#else
main_cell->parts[pid].rho_dh,
main_cell->parts[pid].density.rho_dh,
#endif
main_cell->parts[pid].density.wcount,
main_cell->parts[pid].density.wcount_dh,
......@@ -238,10 +236,8 @@ void dump_particle_fields(char *fileName, struct cell *main_cell,
cj->parts[pjd].v[2], hydro_get_density(&cj->parts[pjd]),
#if defined(GIZMO_SPH)
0.f,
#elif defined(HOPKINS_PE_SPH)
main_cell->parts[pjd].density.rho_dh,
#else
main_cell->parts[pjd].rho_dh,
main_cell->parts[pjd].density.rho_dh,
#endif
cj->parts[pjd].density.wcount, cj->parts[pjd].density.wcount_dh,
#if defined(GADGET2_SPH) || defined(DEFAULT_SPH) || defined(HOPKINS_PE_SPH)
......
tests/testInteractions.c
+ 2
− 7
View file @ da18a66d
......@@ -111,13 +111,8 @@ void dump_indv_particle_fields(char *fileName, struct part *p) {
"%13e %13e %13e %10f\n",
p->id, p->x[0], p->x[1], p->x[2], p->v[0], p->v[1], p->v[2],
p->a_hydro[0], p->a_hydro[1], p->a_hydro[2], p->rho,
#ifdef HOPKINS_PE_SPH
p->density.rho_dh,
#else
p->rho_dh,
#endif
p->density.wcount, p->density.wcount_dh, p->force.h_dt,
p->force.v_sig,
p->density.rho_dh, p->density.wcount, p->density.wcount_dh,
p->force.h_dt, p->force.v_sig,
#if defined(GADGET2_SPH)
p->density.div_v, p->density.rot_v[0], p->density.rot_v[1],
p->density.rot_v[2], p->entropy_dt
......
tests/testPair.c
+ 2
− 6
View file @ da18a66d
......@@ -138,10 +138,8 @@ void dump_particle_fields(char *fileName, struct cell *ci, struct cell *cj) {
ci->parts[pid].v[2], hydro_get_density(&ci->parts[pid]),
#if defined(GIZMO_SPH)
0.f,
#elif defined(HOPKINS_PE_SPH)
ci->parts[pid].density.rho_dh,
#else
ci->parts[pid].rho_dh,
ci->parts[pid].density.rho_dh,
#endif
ci->parts[pid].density.wcount, ci->parts[pid].density.wcount_dh,
#if defined(GADGET2_SPH) || defined(DEFAULT_SPH) || defined(HOPKINS_PE_SPH)
......@@ -164,10 +162,8 @@ void dump_particle_fields(char *fileName, struct cell *ci, struct cell *cj) {
cj->parts[pjd].v[2], hydro_get_density(&cj->parts[pjd]),
#if defined(GIZMO_SPH)
0.f,
#elif defined(HOPKINS_PE_SPH)
cj->parts[pjd].density.rho_dh,
#else
cj->parts[pjd].rho_dh,
cj->parts[pjd].density.rho_dh,
#endif
cj->parts[pjd].density.wcount, cj->parts[pjd].density.wcount_dh,
#if defined(GADGET2_SPH) || defined(DEFAULT_SPH) || defined(HOPKINS_PE_SPH)
......
tests/tolerance_27_normal.dat
+ 1
− 1
View file @ da18a66d
# ID pos_x pos_y pos_z v_x v_y v_z rho rho_dh wcount wcount_dh div_v curl_vx curl_vy curl_vz
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 2e-6 2e-5 2e-3 2e-6 2e-6 2e-6 2e-6
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-5 1e-4 2e-5 2e-5 2e-5 2e-5
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 2e-6 1e-5 1e-4 2e-5 2e-5 2e-5 2e-5
tests/tolerance_27_perturbed.dat
+ 1
− 1
View file @ da18a66d
# ID pos_x pos_y pos_z v_x v_y v_z rho rho_dh wcount wcount_dh div_v curl_vx curl_vy curl_vz
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1.2e-6 2e-6 2.1e-5 2e-3 2.1e-6 2e-6 2e-6 2e-6
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-5 1e-4 2e-5 4e-4 4e-4 4e-4
0 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-6 1e-3 1e-5 1e-4 2e-5 4e-4 4e-4 4e-4
0% or .
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