double rate(double energy)
{
double R=rate_vs_electron_energy->call(energy);
if( R!=R ) //R is nan, energy is too high
{
throw gen_exception("energy too high for bremsstrahlung table:", energy);
}
return R;
}
static void gen_mtvscr(DisasContext *ctx)
{
TCGv_ptr p;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
p = gen_avr_ptr(rB(ctx->opcode));
gen_helper_mtvscr(cpu_env, p);
tcg_temp_free_ptr(p);
}
static void gen_mfvscr(DisasContext *ctx)
{
TCGv_i32 t;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
tcg_gen_movi_i64(cpu_avrh[rD(ctx->opcode)], 0);
t = tcg_temp_new_i32();
tcg_gen_ld_i32(t, cpu_env, offsetof(CPUPPCState, vscr));
tcg_gen_extu_i32_i64(cpu_avrl[rD(ctx->opcode)], t);
tcg_temp_free_i32(t);
}
static void gen_vsbox(DisasContext *ctx)
{
TCGv_ptr ra, rd;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
ra = gen_avr_ptr(rA(ctx->opcode));
rd = gen_avr_ptr(rD(ctx->opcode));
gen_helper_vsbox(rd, ra);
tcg_temp_free_ptr(ra);
tcg_temp_free_ptr(rd);
}
static void gen_vmrgow(DisasContext *ctx)
{
int VT, VA, VB;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
VT = rD(ctx->opcode);
VA = rA(ctx->opcode);
VB = rB(ctx->opcode);
tcg_gen_deposit_i64(cpu_avrh[VT], cpu_avrh[VB], cpu_avrh[VA], 32, 32);
tcg_gen_deposit_i64(cpu_avrl[VT], cpu_avrl[VB], cpu_avrl[VA], 32, 32);
}
static void gen_lvsr(DisasContext *ctx)
{
TCGv_ptr rd;
TCGv EA;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
EA = tcg_temp_new();
gen_addr_reg_index(ctx, EA);
rd = gen_avr_ptr(rD(ctx->opcode));
gen_helper_lvsr(rd, EA);
tcg_temp_free(EA);
tcg_temp_free_ptr(rd);
}
gsl::vector force(gsl::vector &position, gsl::vector &momentum, double time, int charge)
{
//values
double momentum_squared=momentum.sum_of_squares();
double momentum_magnitude=sqrt(momentum_squared);
double G=gamma(momentum_squared);
double inverse_gamma=1.0/G;
//electric field
gsl::vector force=charge*E_field->get(position, time);
//magnetic field
gsl::vector B=charge*B_field->get(position, time);
force[0]+=inverse_gamma*(momentum[1]*B[2]-momentum[2]*B[1]);
force[1]+=inverse_gamma*(momentum[2]*B[0]-momentum[0]*B[2]);
force[2]+=inverse_gamma*(momentum[0]*B[1]-momentum[1]*B[0]);
//ionization friction
double friction=-1;
if(charge==-1)
{
if(remove_moller==0 or remove_moller==1) //if not removing moller losses, or constant min_energy
{
friction=electron_table.electron_lookup(momentum_squared);
}
else if(remove_moller==2) //variable min energy
{
friction=electron_table.electron_lookup_variable_RML(momentum_squared, min_energy);
}
}
else
{
throw gen_exception("positrons not implemented");
////positrons not implemented
//friction=ionization.positron_lookup(momentum_squared);
}
//friction*=0.2;
if(friction>0) //don't want weird stuff
{
force[0]-=friction*momentum[0]/momentum_magnitude;
force[1]-=friction*momentum[1]/momentum_magnitude;
force[2]-=friction*momentum[2]/momentum_magnitude;
}
return force;
}
static void gen_vsldoi(DisasContext *ctx)
{
TCGv_ptr ra, rb, rd;
TCGv_i32 sh;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
ra = gen_avr_ptr(rA(ctx->opcode));
rb = gen_avr_ptr(rB(ctx->opcode));
rd = gen_avr_ptr(rD(ctx->opcode));
sh = tcg_const_i32(VSH(ctx->opcode));
gen_helper_vsldoi (rd, ra, rb, sh);
tcg_temp_free_ptr(ra);
tcg_temp_free_ptr(rb);
tcg_temp_free_ptr(rd);
tcg_temp_free_i32(sh);
}
static void gen_vmrgew(DisasContext *ctx)
{
TCGv_i64 tmp;
int VT, VA, VB;
if (unlikely(!ctx->altivec_enabled)) {
gen_exception(ctx, POWERPC_EXCP_VPU);
return;
}
VT = rD(ctx->opcode);
VA = rA(ctx->opcode);
VB = rB(ctx->opcode);
tmp = tcg_temp_new_i64();
tcg_gen_shri_i64(tmp, cpu_avrh[VB], 32);
tcg_gen_deposit_i64(cpu_avrh[VT], cpu_avrh[VA], tmp, 0, 32);
tcg_gen_shri_i64(tmp, cpu_avrl[VB], 32);
tcg_gen_deposit_i64(cpu_avrl[VT], cpu_avrl[VA], tmp, 0, 32);
tcg_temp_free_i64(tmp);
}
void charged_particle_RungeKuttaDP(electron_T *particle)
// run Dormand-Prince Runge-Kutta with continuous extension, does not rely on the FSAL property
{
if(particle->pos_K_interpolant.size()==0)
//need to initialize particle
{
particle->pos_K_interpolant.reserve(8);
particle->mom_K_interpolant.reserve(8);
for(int i=0; i<8; i++)
{
particle->pos_K_interpolant.push_back(gsl::vector({0,0,0}));
particle->mom_K_interpolant.push_back(gsl::vector({0,0,0}));
}
}
bool acceptable=false;
//print("run:", particle.next_timestep);//(sqrt(particle.momentum.sum_of_squares()+1)-1)*510);
int N=0;
while(not acceptable)
{
N++;
particle->timestep=particle->next_timestep;
if(particle->timestep>maximum_timestep)
{
particle->timestep=maximum_timestep;
}
if(particle->timestep != particle->timestep)
{
throw gen_exception("timestep is Nan");
}
gsl::vector pos_step=particle->position;
gsl::vector mom_step=particle->momentum;
double time=particle->current_time;
gsl::vector K_1_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_1_mom=force(pos_step, mom_step, time, particle->charge); //note that this is a bit redundant. We could calculate this once at the beginning. It doesn't change if stepsize changes
K_1_pos*=particle->timestep;
K_1_mom*=particle->timestep;
pos_step=K_1_pos*(1.0/5.0);
mom_step=K_1_mom*(1.0/5.0);
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep*(1.0/5.0);
gsl::vector K_2_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_2_mom=force(pos_step, mom_step, time, particle->charge);
K_2_pos*=particle->timestep;
K_2_mom*=particle->timestep;
pos_step=K_1_pos*(3.0/40.0);
mom_step=K_1_mom*(3.0/40.0);
pos_step.mult_add( K_2_pos, (9.0/40.0) );
mom_step.mult_add( K_2_mom, (9.0/40.0) );
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep*3.0/10.0;
gsl::vector K_3_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_3_mom=force(pos_step, mom_step, time, particle->charge);
K_3_pos*=particle->timestep;
K_3_mom*=particle->timestep;
pos_step=K_1_pos*(44.0/45.0);
mom_step=K_1_mom*(44.0/45.0);
pos_step.mult_add( K_2_pos, -(56.0/15.0) );
mom_step.mult_add( K_2_mom, -(56.0/15.0) );
pos_step.mult_add( K_3_pos, (32.0/9.0) );
mom_step.mult_add( K_3_mom, (32.0/9.0) );
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep*(4.0/5.0);
gsl::vector K_4_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_4_mom=force(pos_step, mom_step, time, particle->charge);
K_4_pos*=particle->timestep;
K_4_mom*=particle->timestep;
pos_step=K_1_pos*(19372.0/6561.0);
mom_step=K_1_mom*(19372.0/6561.0);
pos_step.mult_add( K_2_pos, -(25360.0/2187.0) );
mom_step.mult_add( K_2_mom, -(25360.0/2187.0) );
pos_step.mult_add( K_3_pos, (64448.0/6561.0) );
mom_step.mult_add( K_3_mom, (64448.0/6561.0) );
pos_step.mult_add( K_4_pos, -(212.0/729.0) );
mom_step.mult_add( K_4_mom, -(212.0/729.0) );
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep*8.0/9.0;
gsl::vector K_5_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_5_mom=force(pos_step, mom_step, time, particle->charge);
K_5_pos*=particle->timestep;
K_5_mom*=particle->timestep;
pos_step=K_1_pos*(9017.0/3168.0);
mom_step=K_1_mom*(9017.0/3168.0);
pos_step.mult_add( K_2_pos, -(355.0/33.0) );
mom_step.mult_add( K_2_mom, -(355.0/33.0) );
pos_step.mult_add( K_3_pos, (46732.0/5247.0) );
mom_step.mult_add( K_3_mom, (46732.0/5247.0) );
pos_step.mult_add( K_4_pos, (49.0/176.0) );
mom_step.mult_add( K_4_mom, (49.0/176.0) );
pos_step.mult_add( K_5_pos, -(5103.0/18656.0) );
mom_step.mult_add( K_5_mom, -(5103.0/18656.0) );
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep;
gsl::vector K_6_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_6_mom=force(pos_step, mom_step, time, particle->charge);
K_6_pos*=particle->timestep;
K_6_mom*=particle->timestep;
pos_step=K_1_pos*(35.0/384.0);
mom_step=K_1_mom*(35.0/384.0);
//K2 is zero
pos_step.mult_add( K_3_pos, (500.0/1113.0) );
mom_step.mult_add( K_3_mom, (500.0/1113.0) );
pos_step.mult_add( K_4_pos, (125.0/192.0) );
mom_step.mult_add( K_4_mom, (125.0/192.0) );
pos_step.mult_add( K_5_pos, -(2187.0/6784.0) );
mom_step.mult_add( K_5_mom, -(2187.0/6784.0) );
pos_step.mult_add( K_6_pos, (11.0/84.0) );
mom_step.mult_add( K_6_mom, (11.0/84.0) );
pos_step+=particle->position;
mom_step+=particle->momentum;
time=particle->current_time + particle->timestep;
gsl::vector K_7_pos=mom_step*(1.0/gamma(mom_step));
gsl::vector K_7_mom=force(pos_step, mom_step, time, particle->charge);
K_7_pos*=particle->timestep;
K_7_mom*=particle->timestep;
gsl::vector pos_O4=K_1_pos*(5179.0/57600.0);
gsl::vector mom_O4=K_1_mom*(5179.0/57600.0);
//pos_O4.mult_add( K_2_pos, 0.0 );
//mom_O4.mult_add( K_2_mom, 0.0 );
pos_O4.mult_add( K_3_pos, (7571.0/16695.0) );
mom_O4.mult_add( K_3_mom, (7571.0/16695.0) );
pos_O4.mult_add( K_4_pos, (393.0/640.0) );
mom_O4.mult_add( K_4_mom, (393.0/640.0) );
pos_O4.mult_add( K_5_pos, -(92097.0/339200.0) );
mom_O4.mult_add( K_5_mom, -(92097.0/339200.0) );
pos_O4.mult_add( K_6_pos, (187.0/2100.0) );
mom_O4.mult_add( K_6_mom, (187.0/2100.0) );
pos_O4.mult_add( K_7_pos, (1.0/40.0) );
mom_O4.mult_add( K_7_mom, (1.0/40.0) );
//pos_O4+=particle.position; //don't need to do this
//mom_O4+=particle.momentum;
gsl::vector pos_O5=K_1_pos*(35.0/384.0);
gsl::vector mom_O5=K_1_mom*(35.0/384.0);
//pos_O5.mult_add( K_2_pos, 0.0 );
//mom_O5.mult_add( K_2_mom, 0.0 );
pos_O5.mult_add( K_3_pos, (500.0/1113.0) );
mom_O5.mult_add( K_3_mom, (500.0/1113.0) );
pos_O5.mult_add( K_4_pos, (125.0/192.0) );
mom_O5.mult_add( K_4_mom, (125.0/192.0) );
pos_O5.mult_add( K_5_pos, -(2187.0/6784.0) );
mom_O5.mult_add( K_5_mom, -(2187.0/6784.0) );
pos_O5.mult_add( K_6_pos, (11.0/84.0) );
mom_O5.mult_add( K_6_mom, (11.0/84.0) );
//pos_O5.mult_add( K_7_pos, 0.0 );
//mom_O5.mult_add( K_7_mom, 0.0 );
pos_O4-=pos_O5;//for calculating the error
mom_O4-=mom_O5;
double pos_error_sq=pos_O4.sum_of_squares();
double mom_error_sq=mom_O4.sum_of_squares();
double max_pos_error_sq=rel_tol*rel_tol*pos_O5.sum_of_squares();
double max_mom_error_sq=rel_tol*rel_tol*mom_O5.sum_of_squares();
double err_f=std::min(max_pos_error_sq/pos_error_sq, max_mom_error_sq/mom_error_sq );//note the inverses
pos_O5+=particle->position;
mom_O5+=particle->momentum;
//double pos_error_sq=pos_O4.sum_of_squares();
//double mom_error_sq=mom_O4.sum_of_squares();
//pos_error_sq=pos_tol*pos_tol/pos_error_sq;
//mom_error_sq=mom_tol*mom_tol/mom_error_sq;
if(err_f>1)//error is good, exit
{
//set timestep
particle->interpolant_timestep=particle->timestep;
particle->next_timestep=particle->timestep*kappa*std::pow( std::sqrt(err_f), 0.25);
particle->pos_K_interpolant[0]=particle->position;
particle->mom_K_interpolant[0]=particle->momentum;
particle->pos_K_interpolant[1]=K_1_pos;
particle->mom_K_interpolant[1]=K_1_mom;
particle->pos_K_interpolant[2]=K_2_pos;
particle->mom_K_interpolant[2]=K_2_mom;
particle->pos_K_interpolant[3]=K_3_pos;
particle->mom_K_interpolant[3]=K_3_mom;
particle->pos_K_interpolant[4]=K_4_pos;
particle->mom_K_interpolant[4]=K_4_mom;
particle->pos_K_interpolant[5]=K_5_pos;
particle->mom_K_interpolant[5]=K_5_mom;
particle->pos_K_interpolant[6]=K_6_pos;
particle->mom_K_interpolant[6]=K_6_mom;
particle->pos_K_interpolant[7]=K_7_pos;
particle->mom_K_interpolant[7]=K_7_mom;
particle->current_time+=particle->timestep;
particle->position=pos_O5;
particle->momentum=mom_O5;
acceptable=true;
}
else
{//repeat with new timestep
if(N>100)
{
throw gen_exception("error in Dormand-Prince RK: ", N);
}
//print(pos_O4.sum_of_squares(), mom_O4.sum_of_squares(), max_pos_error_sq, max_mom_error_sq);
particle->next_timestep=particle->timestep*kappa*std::pow( std::sqrt(err_f), 0.20);
acceptable=false;
}
}
}
