def no_collapse_expect_out(num_times,expect_out):
##Calculates xpect.values at times tlist if no collapse ops. given
#
#------------------------------------
opt=odeconfig.options
if odeconfig.tflag in array([1,10,11]):
ODE=ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params('+odeconfig.string+')', '<string>', 'exec')
exec(code)
elif odeconfig.tflag==2:
ODE=ode(cRHStd)
elif odeconfig.tflag in array([20,22]):
ODE=ode(tdRHStd)
elif odeconfig.tflag==3:
ODE=ode(pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
ODE.set_integrator('zvode',method=opt.method,order=opt.order,atol=opt.atol,rtol=opt.rtol,nsteps=opt.nsteps,first_step=opt.first_step,min_step=opt.min_step,max_step=opt.max_step) #initialize ODE solver for RHS
ODE.set_initial_value(odeconfig.psi0,odeconfig.tlist[0]) #set initial conditions
for jj in range(odeconfig.e_num):
expect_out[jj][0]=mc_expect(odeconfig.e_ops_data[jj],odeconfig.e_ops_ind[jj],odeconfig.e_ops_ptr[jj],odeconfig.e_ops_isherm[jj],odeconfig.psi0)
for k in range(1,num_times):
ODE.integrate(odeconfig.tlist[k],step=0) #integrate up to tlist[k]
if ODE.successful():
state=ODE.y/norm(ODE.y)
for jj in range(odeconfig.e_num):
expect_out[jj][k]=mc_expect(odeconfig.e_ops_data[jj],odeconfig.e_ops_ind[jj],odeconfig.e_ops_ptr[jj],odeconfig.e_ops_isherm[jj],state)
else:
raise ValueError('Error in ODE solver')
return expect_out #return times and expectiation values
def d1_psi_heterodyne(A, psi):
"""
not working/tested
Todo: cythonize
"""
e1 = mc_expect(A[0].data, A[0].indices, A[0].indptr, 0, psi)
B = A[0].T.conj()
e2 = mc_expect(B.data, B.indices, B.indptr, 0, psi)
return ( e2 * spmv(A[0].data, A[0].indices, A[0].indptr, psi)
- 0.5 * spmv(A[2].data, A[2].indices, A[2].indptr, psi)
- 0.5 * e1 * e2 * psi)
def d1_psi_heterodyne(A, psi):
"""
not working/tested
Todo: cythonize
"""
e1 = mc_expect(A[0].data, A[0].indices, A[0].indptr, 0, psi)
B = A[0].T.conj()
e2 = mc_expect(B.data, B.indices, B.indptr, 0, psi)
return (e2 * spmv(A[0].data, A[0].indices, A[0].indptr, psi) -
0.5 * spmv(A[2].data, A[2].indices, A[2].indptr, psi) -
0.5 * e1 * e2 * psi)
def no_collapse_expect_out(num_times, expect_out):
##Calculates xpect.values at times tlist if no collapse ops. given
#
#------------------------------------
opt = odeconfig.options
if odeconfig.tflag in array([1, 10, 11]):
ODE = ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params(' + odeconfig.string + ')',
'<string>', 'exec')
exec(code)
elif odeconfig.tflag == 2:
ODE = ode(cRHStd)
elif odeconfig.tflag in array([20, 22]):
ODE = ode(tdRHStd)
elif odeconfig.tflag == 3:
ODE = ode(pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
ODE.set_integrator('zvode',
method=opt.method,
order=opt.order,
atol=opt.atol,
rtol=opt.rtol,
nsteps=opt.nsteps,
first_step=opt.first_step,
min_step=opt.min_step,
max_step=opt.max_step) #initialize ODE solver for RHS
ODE.set_initial_value(odeconfig.psi0,
odeconfig.tlist[0]) #set initial conditions
for jj in range(odeconfig.e_num):
expect_out[jj][0] = mc_expect(odeconfig.e_ops_data[jj],
odeconfig.e_ops_ind[jj],
odeconfig.e_ops_ptr[jj],
odeconfig.e_ops_isherm[jj],
odeconfig.psi0)
for k in range(1, num_times):
ODE.integrate(odeconfig.tlist[k], step=0) #integrate up to tlist[k]
if ODE.successful():
state = ODE.y / norm(ODE.y)
for jj in range(odeconfig.e_num):
expect_out[jj][k] = mc_expect(odeconfig.e_ops_data[jj],
odeconfig.e_ops_ind[jj],
odeconfig.e_ops_ptr[jj],
odeconfig.e_ops_isherm[jj],
state)
else:
raise ValueError('Error in ODE solver')
return expect_out #return times and expectiation values
def run(self):
if odeconfig.c_num == 0:
if odeconfig.ntraj != 1: #check if ntraj!=1 which is pointless for no collapse operators
odeconfig.ntraj = 1
print(
'No collapse operators specified.\nRunning a single trajectory only.\n'
)
if odeconfig.e_num == 0: # return psi Qobj at each requested time
self.psi_out = no_collapse_psi_out(self.num_times,
self.psi_out)
else: # return expectation values of requested operators
self.expect_out = no_collapse_expect_out(
self.num_times, self.expect_out)
elif odeconfig.c_num != 0:
self.seed = array([
int(ceil(random.rand() * 1e4)) for ll in range(odeconfig.ntraj)
])
if odeconfig.e_num == 0:
mc_alg_out = zeros((self.num_times), dtype=ndarray)
mc_alg_out[0] = odeconfig.psi0
else:
#PRE-GENERATE LIST OF EXPECTATION VALUES
mc_alg_out = []
for i in range(odeconfig.e_num):
if odeconfig.e_ops_isherm[
i]: #preallocate real array of zeros
mc_alg_out.append(zeros(self.num_times))
else: #preallocate complex array of zeros
mc_alg_out.append(zeros(self.num_times, dtype=complex))
mc_alg_out[i][0] = mc_expect(odeconfig.e_ops_data[i],
odeconfig.e_ops_ind[i],
odeconfig.e_ops_ptr[i],
odeconfig.e_ops_isherm[i],
odeconfig.psi0)
#set arguments for input to monte-carlo
args = (mc_alg_out, odeconfig.options, odeconfig.tlist,
self.num_times, self.seed)
if not odeconfig.options.gui:
self.parallel(args, self)
else:
if qutip.settings.qutip_gui == "PYSIDE":
from PySide import QtGui, QtCore
elif qutip.settings.qutip_gui == "PYQT4":
from PyQt4 import QtGui, QtCore
from gui.ProgressBar import ProgressBar, Pthread
app = QtGui.QApplication.instance(
) #checks if QApplication already exists (needed for iPython)
if not app: #create QApplication if it doesnt exist
app = QtGui.QApplication(sys.argv)
thread = Pthread(target=self.parallel, args=args, top=self)
self.bar = ProgressBar(self, thread, odeconfig.ntraj,
self.cpus)
QtCore.QTimer.singleShot(0, self.bar.run)
self.bar.show()
self.bar.activateWindow()
self.bar.raise_()
app.exec_()
return
def d2_psi_heterodyne(A, psi):
"""
not working/tested
Todo: cythonize
"""
e1 = mc_expect(A[0].data, A[0].indices, A[0].indptr, 0, psi)
return spmv(A[0].data, A[0].indices, A[0].indptr, psi) - e1 * psi
def d2_psi_heterodyne(A, psi):
"""
not working/tested
Todo: cythonize
"""
e1 = mc_expect(A[0].data, A[0].indices, A[0].indptr, 0, psi)
return spmv(A[0].data, A[0].indices, A[0].indptr, psi) - e1 * psi
def d2_psi_homodyne(A, psi):
"""
OK
Todo: cythonize
"""
e1 = mc_expect(A[1].data, A[1].indices, A[1].indptr, 0, psi)
return spmv(A[0].data, A[0].indices, A[0].indptr, psi) - 0.5 * e1 * psi
def d2_psi_homodyne(A, psi):
"""
OK
Todo: cythonize
"""
e1 = mc_expect(A[1].data, A[1].indices, A[1].indptr, 0, psi)
return (spmv(A[0].data, A[0].indices, A[0].indptr, psi) - 0.5 * e1 * psi)
def __init__(self):
#-----------------------------------#
# INIT MC CLASS
#-----------------------------------#
#----MAIN OBJECT PROPERTIES--------------------#
##holds instance of the ProgressBar class
self.bar=None
##holds instance of the Pthread class
self.thread=None
#Number of completed trajectories
self.count=0
##step-size for count attribute
self.step=1
##Percent of trajectories completed
self.percent=0.0
##used in implimenting the command line progress ouput
self.level=0.1
##times at which to output state vectors or expectation values
##number of time steps in tlist
self.num_times=len(odeconfig.tlist)
#holds seed for random number generator
self.seed=None
#holds expected time to completion
self.st=None
#number of cpus to be used
self.cpus=odeconfig.options.num_cpus
#set output variables, even if they are not used to simplify output code.
self.psi_out=None
self.expect_out=None
self.collapse_times_out=None
self.which_op_out=None
#FOR EVOLUTION FOR NO COLLAPSE OPERATORS
if odeconfig.c_num==0:
if odeconfig.e_num==0:
##Output array of state vectors calculated at times in tlist
self.psi_out=array([Qobj()]*self.num_times)#preallocate array of Qobjs
elif odeconfig.e_num!=0:#no collpase expectation values
##List of output expectation values calculated at times in tlist
self.expect_out=[]
for i in range(odeconfig.e_num):
if odeconfig.e_ops_isherm[i]:#preallocate real array of zeros
self.expect_out.append(zeros(self.num_times))
else:#preallocate complex array of zeros
self.expect_out.append(zeros(self.num_times,dtype=complex))
self.expect_out[i][0]=mc_expect(odeconfig.e_ops_data[i],odeconfig.e_ops_ind[i],odeconfig.e_ops_ptr[i],odeconfig.e_ops_isherm[i],odeconfig.psi0)
#FOR EVOLUTION WITH COLLAPSE OPERATORS
elif odeconfig.c_num!=0:
#preallocate #ntraj arrays for state vectors, collapse times, and which operator
self.collapse_times_out=zeros((odeconfig.ntraj),dtype=ndarray)
self.which_op_out=zeros((odeconfig.ntraj),dtype=ndarray)
if odeconfig.e_num==0:# if no expectation operators, preallocate #ntraj arrays for state vectors
self.psi_out=array([zeros((self.num_times),dtype=object) for q in range(odeconfig.ntraj)])#preallocate array of Qobjs
else: #preallocate array of lists for expectation values
self.expect_out=[[] for x in range(odeconfig.ntraj)]
def d1_psi_homodyne(A, psi):
"""
OK
Todo: cythonize
"""
e1 = mc_expect(A[1].data, A[1].indices, A[1].indptr, 0, psi)
return 0.5 * (e1 * spmv(A[0].data, A[0].indices, A[0].indptr, psi) - spmv(
A[2].data, A[2].indices, A[2].indptr, psi) - 0.25 * e1**2 * psi)
def d1_psi_homodyne(A, psi):
"""
OK
Todo: cythonize
"""
e1 = mc_expect(A[1].data, A[1].indices, A[1].indptr, 0, psi)
return 0.5 * (e1 * spmv(A[0].data, A[0].indices, A[0].indptr, psi) -
spmv(A[2].data, A[2].indices, A[2].indptr, psi) -
0.25 * e1**2 * psi)
def run(self):
if odeconfig.c_num==0:
if odeconfig.ntraj!=1:#check if ntraj!=1 which is pointless for no collapse operators
odeconfig.ntraj=1
print('No collapse operators specified.\nRunning a single trajectory only.\n')
if odeconfig.e_num==0:# return psi Qobj at each requested time
self.psi_out=_no_collapse_psi_out(self.num_times,self.psi_out)
else:# return expectation values of requested operators
self.expect_out=_no_collapse_expect_out(self.num_times,self.expect_out)
elif odeconfig.c_num!=0:
self.seed=random_integers(1e8,size=odeconfig.ntraj)
if odeconfig.e_num==0:
mc_alg_out=zeros((self.num_times),dtype=ndarray)
if odeconfig.options.mc_avg: #output is averaged states, so use dm
mc_alg_out[0]=odeconfig.psi0*odeconfig.psi0.conj().T
else: #output is not averaged, so write state vectors
mc_alg_out[0]=odeconfig.psi0
else:
#PRE-GENERATE LIST OF EXPECTATION VALUES
mc_alg_out=[]
for i in range(odeconfig.e_num):
if odeconfig.e_ops_isherm[i]:#preallocate real array of zeros
mc_alg_out.append(zeros(self.num_times))
else:#preallocate complex array of zeros
mc_alg_out.append(zeros(self.num_times,dtype=complex))
mc_alg_out[i][0]=mc_expect(odeconfig.e_ops_data[i],odeconfig.e_ops_ind[i],odeconfig.e_ops_ptr[i],odeconfig.e_ops_isherm[i],odeconfig.psi0)
#set arguments for input to monte-carlo
args=(mc_alg_out,odeconfig.options,odeconfig.tlist,self.num_times,self.seed)
if not odeconfig.options.gui:
self.parallel(args,self)
else:
if qutip.settings.qutip_gui=="PYSIDE":
from PySide import QtGui,QtCore
elif qutip.settings.qutip_gui=="PYQT4":
from PyQt4 import QtGui,QtCore
from gui.ProgressBar import ProgressBar,Pthread
app=QtGui.QApplication.instance()#checks if QApplication already exists (needed for iPython)
if not app:#create QApplication if it doesnt exist
app = QtGui.QApplication(sys.argv)
thread=Pthread(target=self.parallel,args=args,top=self)
self.bar=ProgressBar(self,thread,odeconfig.ntraj,self.cpus)
QtCore.QTimer.singleShot(0,self.bar.run)
self.bar.show()
self.bar.activateWindow()
self.bar.raise_()
app.exec_()
return
def mc_alg_evolve(nt,args):
"""
Monte-Carlo algorithm returning state-vector or expectation values at times tlist for a single trajectory.
"""
#get input data
mc_alg_out,opt,tlist,num_times,seeds=args
#number of operators of each type
num_expect=odeconfig.e_num
num_collapse=odeconfig.c_num
collapse_times=[] #times at which collapse occurs
which_oper=[] # which operator did the collapse
#SEED AND RNG AND GENERATE
random.seed(seeds[nt])
rand_vals=random.rand(2)#first rand is collapse norm, second is which operator
#CREATE ODE OBJECT CORRESPONDING TO DESIRED TIME-DEPENDENCE
if odeconfig.tflag in array([1,10,11]):
ODE=ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params('+odeconfig.string+')', '<string>', 'exec')
exec(code)
elif odeconfig.tflag==2:
ODE=ode(cRHStd)
elif odeconfig.tflag in array([20,22]):
ODE=ode(tdRHStd)
elif odeconfig.tflag==3:
ODE=ode(pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
#initialize ODE solver for RHS
ODE.set_integrator('zvode',method=opt.method,order=opt.order,atol=opt.atol,rtol=opt.rtol,nsteps=opt.nsteps,
first_step=opt.first_step,min_step=opt.min_step,max_step=opt.max_step)
#set initial conditions
ODE.set_initial_value(odeconfig.psi0,tlist[0])
#RUN ODE UNTIL EACH TIME IN TLIST
cinds=arange(num_collapse)
for k in range(1,num_times):
#ODE WHILE LOOP FOR INTEGRATE UP TO TIME TLIST[k]
while ODE.successful() and ODE.t<tlist[k]:
last_t=ODE.t;last_y=ODE.y
ODE.integrate(tlist[k],step=1) #integrate up to tlist[k], one step at a time.
psi_nrm2=norm(ODE.y,2)**2
if psi_nrm2<=rand_vals[0]:# <== collpase has occured
collapse_times.append(ODE.t)
#some string based collapse operators
if odeconfig.tflag in array([1,11]):
n_dp=[mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_const_inds]
exec(odeconfig.col_expect_code) #calculates the expectation values for time-dependent norm collapse operators
n_dp=array(n_dp)
#some Python function based collapse operators
elif odeconfig.tflag in array([2,20,22]):
n_dp=[mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_const_inds]
n_dp+=[abs(odeconfig.c_funcs[i](ODE.t,odeconfig.c_func_args))**2*mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_td_inds]
n_dp=array(n_dp)
#all constant collapse operators.
else:
n_dp=array([mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in range(num_collapse)])
#determine which operator does collapse
kk=cumsum(n_dp/sum(n_dp))
j=cinds[kk>=rand_vals[1]][0]
which_oper.append(j) #record which operator did collapse
if j in odeconfig.c_const_inds:
state=spmv(odeconfig.c_ops_data[j],odeconfig.c_ops_ind[j],odeconfig.c_ops_ptr[j],ODE.y)
else:
if odeconfig.tflag in array([1,11]):
exec(odeconfig.col_spmv_code)#calculates the state vector for collapse by a time-dependent collapse operator
else:
state=odeconfig.c_funcs[j](ODE.t,odeconfig.c_func_args)*spmv(odeconfig.c_ops_data[j],odeconfig.c_ops_ind[j],odeconfig.c_ops_ptr[j],ODE.y)
state_nrm=norm(state,2)
ODE.set_initial_value(state/state_nrm,ODE.t)
rand_vals=random.rand(2)
#-------------------------------------------------------
###--after while loop--####
psi=copy(ODE.y)
if ODE.t>last_t:
psi=(psi-last_y)/(ODE.t-last_t)*(tlist[k]-last_t)+last_y
epsi=psi/norm(psi,2)
if num_expect==0:
mc_alg_out[k]=epsi
else:
for jj in range(num_expect):
mc_alg_out[jj][k]=mc_expect(odeconfig.e_ops_data[jj],odeconfig.e_ops_ind[jj],odeconfig.e_ops_ptr[jj],odeconfig.e_ops_isherm[jj],epsi)
#RETURN VALUES
if num_expect==0:
mc_alg_out=array([Qobj(k,odeconfig.psi0_dims,odeconfig.psi0_shape,fast='mc') for k in mc_alg_out])
return nt,mc_alg_out,array(collapse_times),array(which_oper)
else:
return nt,mc_alg_out,array(collapse_times),array(which_oper)
def _mc_alg_evolve(nt, args):
"""
Monte-Carlo algorithm returning state-vector or expectation values at times tlist for a single trajectory.
"""
#get input data
mc_alg_out, opt, tlist, num_times, seeds = args
collapse_times = [] #times at which collapse occurs
which_oper = [] # which operator did the collapse
#SEED AND RNG AND GENERATE
prng = RandomState(seeds[nt])
rand_vals = prng.rand(
2) #first rand is collapse norm, second is which operator
#CREATE ODE OBJECT CORRESPONDING TO DESIRED TIME-DEPENDENCE
if odeconfig.tflag in array([1, 10, 11]):
ODE = ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params(' + odeconfig.string + ')',
'<string>', 'exec')
exec(code)
elif odeconfig.tflag == 2:
ODE = ode(_cRHStd)
elif odeconfig.tflag in array([20, 22]):
ODE = ode(_tdRHStd)
elif odeconfig.tflag == 3:
ODE = ode(_pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
#initialize ODE solver for RHS
ODE.set_integrator('zvode',
method=opt.method,
order=opt.order,
atol=opt.atol,
rtol=opt.rtol,
nsteps=opt.nsteps,
first_step=opt.first_step,
min_step=opt.min_step,
max_step=opt.max_step)
#set initial conditions
ODE.set_initial_value(odeconfig.psi0, tlist[0])
#make array for collapse operator inds
cinds = arange(odeconfig.c_num)
#RUN ODE UNTIL EACH TIME IN TLIST
for k in range(1, num_times):
#ODE WHILE LOOP FOR INTEGRATE UP TO TIME TLIST[k]
while ODE.t < tlist[k]:
t_prev = ODE.t
y_prev = ODE.y
norm2_prev = norm(ODE.y, 2)**2
ODE.integrate(
tlist[k],
step=1) #integrate up to tlist[k], one step at a time.
if not ODE.successful():
raise Exception("ZVODE failed!")
#check if ODE jumped over tlist[k], if so, integrate until tlist exactly
if ODE.t > tlist[k]:
ODE.set_initial_value(y_prev, t_prev)
ODE.integrate(tlist[k], step=0)
if not ODE.successful():
raise Exception("ZVODE failed!")
norm2_psi = norm(ODE.y, 2)**2
if norm2_psi <= rand_vals[0]: # <== collpase has occured
#find collpase time to within specified tolerance
#---------------------------------------------------
ii = 0
t_final = ODE.t
while ii < odeconfig.norm_steps:
ii += 1
#t_guess=t_prev+(rand_vals[0]-norm2_prev)/(norm2_psi-norm2_prev)*(t_final-t_prev)
t_guess = t_prev + log(norm2_prev / rand_vals[0]) / log(
norm2_prev / norm2_psi) * (t_final - t_prev)
ODE.set_initial_value(y_prev, t_prev)
ODE.integrate(t_guess, step=0)
if not ODE.successful():
raise Exception(
"ZVODE failed after adjusting step size!")
norm2_guess = norm(ODE.y, 2)**2
if abs(rand_vals[0] -
norm2_guess) < odeconfig.norm_tol * rand_vals[0]:
break
elif (norm2_guess < rand_vals[0]):
# t_guess is still > t_jump
t_final = t_guess
norm2_psi = norm2_guess
else:
# t_guess < t_jump
t_prev = t_guess
y_prev = ODE.y
norm2_prev = norm2_guess
if ii > odeconfig.norm_steps:
raise Exception(
"Norm tolerance not reached. Increase accuracy of ODE solver or Odeoptions.norm_steps."
)
#---------------------------------------------------
collapse_times.append(ODE.t)
#some string based collapse operators
if odeconfig.tflag in array([1, 11]):
n_dp = [
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_const_inds
]
_locals = locals()
exec(
odeconfig.col_expect_code, globals(), _locals
) #calculates the expectation values for time-dependent norm collapse operators
n_dp = array(_locals['n_dp'])
#some Python function based collapse operators
elif odeconfig.tflag in array([2, 20, 22]):
n_dp = [
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_const_inds
]
n_dp += [
abs(odeconfig.c_funcs[i](ODE.t, odeconfig.c_func_args))
**2 * mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_td_inds
]
n_dp = array(n_dp)
#all constant collapse operators.
else:
n_dp = array([
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in range(odeconfig.c_num)
])
#determine which operator does collapse
kk = cumsum(n_dp / sum(n_dp))
j = cinds[kk >= rand_vals[1]][0]
which_oper.append(j) #record which operator did collapse
if j in odeconfig.c_const_inds:
state = spmv(odeconfig.c_ops_data[j],
odeconfig.c_ops_ind[j],
odeconfig.c_ops_ptr[j], ODE.y)
else:
if odeconfig.tflag in array([1, 11]):
_locals = locals()
exec(
odeconfig.col_spmv_code, globals(), _locals
) #calculates the state vector for collapse by a time-dependent collapse operator
state = _locals['state']
else:
state = odeconfig.c_funcs[j](
ODE.t, odeconfig.c_func_args) * spmv(
odeconfig.c_ops_data[j],
odeconfig.c_ops_ind[j], odeconfig.c_ops_ptr[j],
ODE.y)
state = state / norm(state, 2)
ODE.set_initial_value(state, ODE.t)
rand_vals = prng.rand(2)
#-------------------------------------------------------
###--after while loop--####
out_psi = ODE.y / norm(ODE.y, 2)
if odeconfig.e_num == 0:
if odeconfig.options.mc_avg:
mc_alg_out[k] = out_psi * out_psi.conj().T
else:
mc_alg_out[k] = out_psi
else:
for jj in range(odeconfig.e_num):
mc_alg_out[jj][k] = mc_expect(odeconfig.e_ops_data[jj],
odeconfig.e_ops_ind[jj],
odeconfig.e_ops_ptr[jj],
odeconfig.e_ops_isherm[jj],
out_psi)
#RETURN VALUES
if odeconfig.e_num == 0:
if odeconfig.options.mc_avg:
mc_alg_out = array([
Qobj(k, [odeconfig.psi0_dims[0], odeconfig.psi0_dims[0]],
[odeconfig.psi0_shape[0], odeconfig.psi0_shape[0]],
fast='mc-dm') for k in mc_alg_out
])
else:
mc_alg_out = array([
Qobj(k, odeconfig.psi0_dims, odeconfig.psi0_shape, fast='mc')
for k in mc_alg_out
])
return nt, mc_alg_out, array(collapse_times), array(which_oper)
else:
return nt, mc_alg_out, array(collapse_times), array(which_oper)
def __init__(self):
#-----------------------------------#
# INIT MC CLASS
#-----------------------------------#
#----MAIN OBJECT PROPERTIES--------------------#
##holds instance of the ProgressBar class
self.bar = None
##holds instance of the Pthread class
self.thread = None
#Number of completed trajectories
self.count = 0
##step-size for count attribute
self.step = 1
##Percent of trajectories completed
self.percent = 0.0
##used in implimenting the command line progress ouput
self.level = 0.1
##times at which to output state vectors or expectation values
##number of time steps in tlist
self.num_times = len(odeconfig.tlist)
#holds seed for random number generator
self.seed = None
#holds expected time to completion
self.st = None
#number of cpus to be used
self.cpus = odeconfig.options.num_cpus
#set output variables, even if they are not used to simplify output code.
self.psi_out = None
self.expect_out = None
self.collapse_times_out = None
self.which_op_out = None
#FOR EVOLUTION FOR NO COLLAPSE OPERATORS
if odeconfig.c_num == 0:
if odeconfig.e_num == 0:
##Output array of state vectors calculated at times in tlist
self.psi_out = array(
[Qobj()] * self.num_times) #preallocate array of Qobjs
elif odeconfig.e_num != 0: #no collpase expectation values
##List of output expectation values calculated at times in tlist
self.expect_out = []
for i in range(odeconfig.e_num):
if odeconfig.e_ops_isherm[
i]: #preallocate real array of zeros
self.expect_out.append(zeros(self.num_times))
else: #preallocate complex array of zeros
self.expect_out.append(
zeros(self.num_times, dtype=complex))
self.expect_out[i][0] = mc_expect(
odeconfig.e_ops_data[i], odeconfig.e_ops_ind[i],
odeconfig.e_ops_ptr[i], odeconfig.e_ops_isherm[i],
odeconfig.psi0)
#FOR EVOLUTION WITH COLLAPSE OPERATORS
elif odeconfig.c_num != 0:
#preallocate #ntraj arrays for state vectors, collapse times, and which operator
self.collapse_times_out = zeros((odeconfig.ntraj), dtype=ndarray)
self.which_op_out = zeros((odeconfig.ntraj), dtype=ndarray)
if odeconfig.e_num == 0: # if no expectation operators, preallocate #ntraj arrays for state vectors
self.psi_out = array([
zeros((self.num_times), dtype=object)
for q in range(odeconfig.ntraj)
]) #preallocate array of Qobjs
else: #preallocate array of lists for expectation values
self.expect_out = [[] for x in range(odeconfig.ntraj)]
def _mc_alg_evolve(nt,args):
"""
Monte-Carlo algorithm returning state-vector or expectation values at times tlist for a single trajectory.
"""
#get input data
mc_alg_out,opt,tlist,num_times,seeds=args
collapse_times=[] #times at which collapse occurs
which_oper=[] # which operator did the collapse
#SEED AND RNG AND GENERATE
prng = RandomState(seeds[nt])
rand_vals=prng.rand(2)#first rand is collapse norm, second is which operator
#CREATE ODE OBJECT CORRESPONDING TO DESIRED TIME-DEPENDENCE
if odeconfig.tflag in array([1,10,11]):
ODE=ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params('+odeconfig.string+')', '<string>', 'exec')
exec(code)
elif odeconfig.tflag==2:
ODE=ode(_cRHStd)
elif odeconfig.tflag in array([20,22]):
ODE=ode(_tdRHStd)
elif odeconfig.tflag==3:
ODE=ode(_pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
#initialize ODE solver for RHS
ODE.set_integrator('zvode',method=opt.method,order=opt.order,atol=opt.atol,rtol=opt.rtol,nsteps=opt.nsteps,
first_step=opt.first_step,min_step=opt.min_step,max_step=opt.max_step)
#set initial conditions
ODE.set_initial_value(odeconfig.psi0,tlist[0])
#make array for collapse operator inds
cinds=arange(odeconfig.c_num)
#RUN ODE UNTIL EACH TIME IN TLIST
for k in range(1,num_times):
#ODE WHILE LOOP FOR INTEGRATE UP TO TIME TLIST[k]
while ODE.t<tlist[k]:
t_prev=ODE.t;y_prev=ODE.y;norm2_prev=norm(ODE.y,2)**2
ODE.integrate(tlist[k],step=1) #integrate up to tlist[k], one step at a time.
if not ODE.successful():
raise Exception("ZVODE failed!")
#check if ODE jumped over tlist[k], if so, integrate until tlist exactly
if ODE.t>tlist[k]:
ODE.set_initial_value(y_prev,t_prev)
ODE.integrate(tlist[k],step=0)
if not ODE.successful():
raise Exception("ZVODE failed!")
norm2_psi=norm(ODE.y,2)**2
if norm2_psi<=rand_vals[0]:# <== collpase has occured
#find collpase time to within specified tolerance
#---------------------------------------------------
ii=0
t_final=ODE.t
while ii < odeconfig.norm_steps:
ii+=1
#t_guess=t_prev+(rand_vals[0]-norm2_prev)/(norm2_psi-norm2_prev)*(t_final-t_prev)
t_guess=t_prev+log(norm2_prev/rand_vals[0])/log(norm2_prev/norm2_psi)*(t_final-t_prev)
ODE.set_initial_value(y_prev,t_prev)
ODE.integrate(t_guess,step=0)
if not ODE.successful():
raise Exception("ZVODE failed after adjusting step size!")
norm2_guess=norm(ODE.y,2)**2
if abs(rand_vals[0]-norm2_guess) < odeconfig.norm_tol*rand_vals[0]:
break
elif (norm2_guess < rand_vals[0]):
# t_guess is still > t_jump
t_final=t_guess
norm2_psi=norm2_guess
else:
# t_guess < t_jump
t_prev=t_guess
y_prev=ODE.y
norm2_prev=norm2_guess
if ii > odeconfig.norm_steps:
raise Exception("Norm tolerance not reached. Increase accuracy of ODE solver or Odeoptions.norm_steps.")
#---------------------------------------------------
collapse_times.append(ODE.t)
#some string based collapse operators
if odeconfig.tflag in array([1,11]):
n_dp=[mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_const_inds]
_locals = locals()
exec(odeconfig.col_expect_code, globals(), _locals) #calculates the expectation values for time-dependent norm collapse operators
n_dp=array(_locals['n_dp'])
#some Python function based collapse operators
elif odeconfig.tflag in array([2,20,22]):
n_dp=[mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_const_inds]
n_dp+=[abs(odeconfig.c_funcs[i](ODE.t,odeconfig.c_func_args))**2*mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in odeconfig.c_td_inds]
n_dp=array(n_dp)
#all constant collapse operators.
else:
n_dp=array([mc_expect(odeconfig.n_ops_data[i],odeconfig.n_ops_ind[i],odeconfig.n_ops_ptr[i],1,ODE.y) for i in range(odeconfig.c_num)])
#determine which operator does collapse
kk=cumsum(n_dp/sum(n_dp))
j=cinds[kk>=rand_vals[1]][0]
which_oper.append(j) #record which operator did collapse
if j in odeconfig.c_const_inds:
state=spmv(odeconfig.c_ops_data[j],odeconfig.c_ops_ind[j],odeconfig.c_ops_ptr[j],ODE.y)
else:
if odeconfig.tflag in array([1,11]):
_locals = locals()
exec(odeconfig.col_spmv_code, globals(), _locals)#calculates the state vector for collapse by a time-dependent collapse operator
state = _locals['state']
else:
state=odeconfig.c_funcs[j](ODE.t,odeconfig.c_func_args)*spmv(odeconfig.c_ops_data[j],odeconfig.c_ops_ind[j],odeconfig.c_ops_ptr[j],ODE.y)
state=state/norm(state,2)
ODE.set_initial_value(state,ODE.t)
rand_vals=prng.rand(2)
#-------------------------------------------------------
###--after while loop--####
out_psi=ODE.y/norm(ODE.y,2)
if odeconfig.e_num==0:
if odeconfig.options.mc_avg:
mc_alg_out[k]=out_psi*out_psi.conj().T
else:
mc_alg_out[k]=out_psi
else:
for jj in range(odeconfig.e_num):
mc_alg_out[jj][k]=mc_expect(odeconfig.e_ops_data[jj],odeconfig.e_ops_ind[jj],odeconfig.e_ops_ptr[jj],odeconfig.e_ops_isherm[jj],out_psi)
#RETURN VALUES
if odeconfig.e_num==0:
if odeconfig.options.mc_avg:
mc_alg_out=array([Qobj(k,[odeconfig.psi0_dims[0],odeconfig.psi0_dims[0]],[odeconfig.psi0_shape[0],odeconfig.psi0_shape[0]],fast='mc-dm') for k in mc_alg_out])
else:
mc_alg_out=array([Qobj(k,odeconfig.psi0_dims,odeconfig.psi0_shape,fast='mc') for k in mc_alg_out])
return nt,mc_alg_out,array(collapse_times),array(which_oper)
else:
return nt,mc_alg_out,array(collapse_times),array(which_oper)
def mc_alg_evolve(nt, args):
"""
Monte-Carlo algorithm returning state-vector or expectation values at times tlist for a single trajectory.
"""
#get input data
mc_alg_out, opt, tlist, num_times, seeds = args
#number of operators of each type
num_expect = odeconfig.e_num
num_collapse = odeconfig.c_num
collapse_times = [] #times at which collapse occurs
which_oper = [] # which operator did the collapse
#SEED AND RNG AND GENERATE
random.seed(seeds[nt])
rand_vals = random.rand(
2) #first rand is collapse norm, second is which operator
#CREATE ODE OBJECT CORRESPONDING TO DESIRED TIME-DEPENDENCE
if odeconfig.tflag in array([1, 10, 11]):
ODE = ode(odeconfig.tdfunc)
code = compile('ODE.set_f_params(' + odeconfig.string + ')',
'<string>', 'exec')
exec(code)
elif odeconfig.tflag == 2:
ODE = ode(cRHStd)
elif odeconfig.tflag in array([20, 22]):
ODE = ode(tdRHStd)
elif odeconfig.tflag == 3:
ODE = ode(pyRHSc)
else:
ODE = ode(cyq_ode_rhs)
ODE.set_f_params(odeconfig.h_data, odeconfig.h_ind, odeconfig.h_ptr)
#initialize ODE solver for RHS
ODE.set_integrator('zvode',
method=opt.method,
order=opt.order,
atol=opt.atol,
rtol=opt.rtol,
nsteps=opt.nsteps,
first_step=opt.first_step,
min_step=opt.min_step,
max_step=opt.max_step)
#set initial conditions
ODE.set_initial_value(odeconfig.psi0, tlist[0])
#RUN ODE UNTIL EACH TIME IN TLIST
cinds = arange(num_collapse)
for k in range(1, num_times):
#ODE WHILE LOOP FOR INTEGRATE UP TO TIME TLIST[k]
while ODE.successful() and ODE.t < tlist[k]:
last_t = ODE.t
last_y = ODE.y
ODE.integrate(
tlist[k],
step=1) #integrate up to tlist[k], one step at a time.
psi_nrm2 = norm(ODE.y, 2)**2
if psi_nrm2 <= rand_vals[0]: # <== collpase has occured
collapse_times.append(ODE.t)
#some string based collapse operators
if odeconfig.tflag in array([1, 11]):
n_dp = [
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_const_inds
]
exec(
odeconfig.col_expect_code
) #calculates the expectation values for time-dependent norm collapse operators
n_dp = array(n_dp)
#some Python function based collapse operators
elif odeconfig.tflag in array([2, 20, 22]):
n_dp = [
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_const_inds
]
n_dp += [
abs(odeconfig.c_funcs[i](ODE.t, odeconfig.c_func_args))
**2 * mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in odeconfig.c_td_inds
]
n_dp = array(n_dp)
#all constant collapse operators.
else:
n_dp = array([
mc_expect(odeconfig.n_ops_data[i],
odeconfig.n_ops_ind[i],
odeconfig.n_ops_ptr[i], 1, ODE.y)
for i in range(num_collapse)
])
#determine which operator does collapse
kk = cumsum(n_dp / sum(n_dp))
j = cinds[kk >= rand_vals[1]][0]
which_oper.append(j) #record which operator did collapse
if j in odeconfig.c_const_inds:
state = spmv(odeconfig.c_ops_data[j],
odeconfig.c_ops_ind[j],
odeconfig.c_ops_ptr[j], ODE.y)
else:
if odeconfig.tflag in array([1, 11]):
exec(
odeconfig.col_spmv_code
) #calculates the state vector for collapse by a time-dependent collapse operator
else:
state = odeconfig.c_funcs[j](
ODE.t, odeconfig.c_func_args) * spmv(
odeconfig.c_ops_data[j],
odeconfig.c_ops_ind[j], odeconfig.c_ops_ptr[j],
ODE.y)
state_nrm = norm(state, 2)
ODE.set_initial_value(state / state_nrm, ODE.t)
rand_vals = random.rand(2)
#-------------------------------------------------------
###--after while loop--####
psi = copy(ODE.y)
if ODE.t > last_t:
psi = (psi - last_y) / (ODE.t - last_t) * (tlist[k] -
last_t) + last_y
epsi = psi / norm(psi, 2)
if num_expect == 0:
mc_alg_out[k] = epsi
else:
for jj in range(num_expect):
mc_alg_out[jj][k] = mc_expect(odeconfig.e_ops_data[jj],
odeconfig.e_ops_ind[jj],
odeconfig.e_ops_ptr[jj],
odeconfig.e_ops_isherm[jj], epsi)
#RETURN VALUES
if num_expect == 0:
mc_alg_out = array([
Qobj(k, odeconfig.psi0_dims, odeconfig.psi0_shape, fast='mc')
for k in mc_alg_out
])
return nt, mc_alg_out, array(collapse_times), array(which_oper)
else:
return nt, mc_alg_out, array(collapse_times), array(which_oper)
