def push_relativistic(self,dt,E,B=None):
if B:
blah = 0
#t = 0.5*dt*self.chargeOverMass*B
#s = 2.0*t/(1.0 + np.dot(t,t))
#V_minus = self.velocity + 0.5*dt*self.chargeOverMass*E
#V_prime = V_minus + np.cross(V_minus,t)
#V_plus = V_minus + np.cross(V_prime,s)
#self.velocity = V_plus + 0.5*dt*self.chargeOverMass*E
else:
momentum = particleUtils.velocityToMomentum(self.mass,self.velocity)
momentum = momentum + dt*self.charge*E
self.velocity = particleUtils.momentumToVelocity(self.mass,momentum)
self.position = self.position + dt*self.velocity
def push_relativistic(self, dt, E, B=None):
if B:
blah = 0
#t = 0.5*dt*self.chargeOverMass*B
#s = 2.0*t/(1.0 + np.dot(t,t))
#V_minus = self.velocity + 0.5*dt*self.chargeOverMass*E
#V_prime = V_minus + np.cross(V_minus,t)
#V_plus = V_minus + np.cross(V_prime,s)
#self.velocity = V_plus + 0.5*dt*self.chargeOverMass*E
else:
momentum = particleUtils.velocityToMomentum(
self.mass, self.velocity)
momentum = momentum + dt * self.charge * E
self.velocity = particleUtils.momentumToVelocity(
self.mass, momentum)
self.position = self.position + dt * self.velocity
electricFieldAtPoint_R_Rpush = esSolve.electricFieldAtPoint(
electricFieldOnGrid_R, [DX], [X0], electron_R_Rpush.position)
electricFieldAtPoint_R_NRpush = esSolve.electricFieldAtPoint(
electricFieldOnGrid_R, [DX], [X0], electron_R_NRpush.position)
if step == 0:
# Back velocity up 1/2 step
electron_NR.velocity = electron_NR.velocity - 0.5 * DT_NR * (
charge / mass) * electricFieldAtPoint_NR
electron_R_NRpush.velocity = electron_R_NRpush.velocity - 0.5 * DT_R * (
charge / mass) * electricFieldAtPoint_R_NRpush
momentum_0 = particleUtils.velocityToMomentum(
electron_R_Rpush.mass, electron_R_Rpush.velocity)
momentum_minusHalf = momentum_0 - 0.5 * DT_R * electron_R_Rpush.charge * electricFieldAtPoint_R_Rpush
electron_R_Rpush.velocity = particleUtils.momentumToVelocity(
electron_R_Rpush.mass, momentum_minusHalf)
elif step == steps:
# Advance velocity by 1/2 step
electron_NR.velocity = electron_NR.velocity + 0.5 * DT_NR * (
charge / mass) * electricFieldAtPoint_NR
electron_R_NRpush.velocity = electron_R_NRpush.velocity + 0.5 * DT_R * (
charge / mass) * electricFieldAtPoint_R_NRpush
momentum_N = particleUtils.velocityToMomentum(
electron_R_Rpush.mass, electron_R_Rpush.velocity)
momentum_plusHalf = momentum_N + 0.5 * DT_R * electron_R_Rpush.charge * electricFieldAtPoint_R_Rpush
electron_R_Rpush.velocity = particleUtils.momentumToVelocity(
electron_R_Rpush.mass, momentum_plusHalf)
else:
velocities_R_NRpush = [electron_R_NRpush.velocity[0]]
for step in xrange(steps+1):
# Compute E at particle position
electricFieldAtPoint_NR = esSolve.electricFieldAtPoint(electricFieldOnGrid_NR,[DX],[X0],electron_NR.position)
electricFieldAtPoint_R_Rpush = esSolve.electricFieldAtPoint(electricFieldOnGrid_R,[DX],[X0],electron_R_Rpush.position)
electricFieldAtPoint_R_NRpush = esSolve.electricFieldAtPoint(electricFieldOnGrid_R,[DX],[X0],electron_R_NRpush.position)
if step == 0:
# Back velocity up 1/2 step
electron_NR.velocity = electron_NR.velocity - 0.5*DT_NR*(charge/mass)*electricFieldAtPoint_NR
electron_R_NRpush.velocity = electron_R_NRpush.velocity - 0.5*DT_R*(charge/mass)*electricFieldAtPoint_R_NRpush
momentum_0 = particleUtils.velocityToMomentum(electron_R_Rpush.mass,electron_R_Rpush.velocity)
momentum_minusHalf = momentum_0 - 0.5*DT_R*electron_R_Rpush.charge*electricFieldAtPoint_R_Rpush
electron_R_Rpush.velocity = particleUtils.momentumToVelocity(electron_R_Rpush.mass,momentum_minusHalf)
elif step == steps:
# Advance velocity by 1/2 step
electron_NR.velocity = electron_NR.velocity + 0.5*DT_NR*(charge/mass)*electricFieldAtPoint_NR
electron_R_NRpush.velocity = electron_R_NRpush.velocity + 0.5*DT_R*(charge/mass)*electricFieldAtPoint_R_NRpush
momentum_N = particleUtils.velocityToMomentum(electron_R_Rpush.mass,electron_R_Rpush.velocity)
momentum_plusHalf = momentum_N + 0.5*DT_R*electron_R_Rpush.charge*electricFieldAtPoint_R_Rpush
electron_R_Rpush.velocity = particleUtils.momentumToVelocity(electron_R_Rpush.mass,momentum_plusHalf)
else:
# Push particle
electron_NR.push(DT_NR,electricFieldAtPoint_NR)
electron_R_Rpush.push_relativistic(DT_R,electricFieldAtPoint_R_Rpush)
electron_R_NRpush.push(DT_R,electricFieldAtPoint_R_NRpush)