Example #1
0
def _td_brmesolve(H,
                  psi0,
                  tlist,
                  a_ops=[],
                  e_ops=[],
                  c_ops=[],
                  use_secular=True,
                  tol=qset.atol,
                  options=None,
                  progress_bar=None,
                  _safe_mode=True):

    if isket(psi0):
        rho0 = ket2dm(psi0)
    else:
        rho0 = psi0
    nrows = rho0.shape[0]

    H_terms = []
    H_td_terms = []
    H_obj = []
    A_terms = []
    A_td_terms = []
    C_terms = []
    C_td_terms = []
    C_obj = []
    spline_count = [0, 0]

    if isinstance(H, Qobj):
        H_terms.append(H.full('f'))
        H_td_terms.append('1')
    else:
        for kk, h in enumerate(H):
            if isinstance(h, Qobj):
                H_terms.append(h.full('f'))
                H_td_terms.append('1')
            elif isinstance(h, list):
                H_terms.append(h[0].full('f'))
                if isinstance(h[1], Cubic_Spline):
                    H_obj.append(h[1].coeffs)
                    spline_count[0] += 1
                H_td_terms.append(h[1])
            else:
                raise Exception('Invalid Hamiltonian specifiction.')

    for kk, c in enumerate(c_ops):
        if isinstance(c, Qobj):
            C_terms.append(c.full('f'))
            C_td_terms.append('1')
        elif isinstance(c, list):
            C_terms.append(c[0].full('f'))
            if isinstance(c[1], Cubic_Spline):
                C_obj.append(c[1].coeffs)
                spline_count[0] += 1
            C_td_terms.append(c[1])
        else:
            raise Exception('Invalid collape operator specifiction.')

    for kk, a in enumerate(a_ops):
        if isinstance(a, list):
            A_terms.append(a[0].full('f'))
            A_td_terms.append(a[1])
            if isinstance(a[1], tuple):
                if not len(a[1]) == 2:
                    raise Exception('Tuple must be len=2.')
                if isinstance(a[1][0], Cubic_Spline):
                    spline_count[1] += 1
                if isinstance(a[1][1], Cubic_Spline):
                    spline_count[1] += 1
        else:
            raise Exception('Invalid bath-coupling specifiction.')

    string_list = []
    for kk, _ in enumerate(H_td_terms):
        string_list.append("H_terms[{0}]".format(kk))
    for kk, _ in enumerate(H_obj):
        string_list.append("H_obj[{0}]".format(kk))
    for kk, _ in enumerate(C_td_terms):
        string_list.append("C_terms[{0}]".format(kk))
    for kk, _ in enumerate(C_obj):
        string_list.append("C_obj[{0}]".format(kk))
    for kk, _ in enumerate(A_td_terms):
        string_list.append("A_terms[{0}]".format(kk))
    #Add nrows to parameters
    string_list.append('nrows')
    parameter_string = ",".join(string_list)

    #
    # generate and compile new cython code if necessary
    #
    if not options.rhs_reuse or config.tdfunc is None:
        if options.rhs_filename is None:
            config.tdname = "rhs" + str(os.getpid()) + str(config.cgen_num)
        else:
            config.tdname = opt.rhs_filename
        cgen = BR_Codegen(
            h_terms=len(H_terms),
            h_td_terms=H_td_terms,
            h_obj=H_obj,
            c_terms=len(C_terms),
            c_td_terms=C_td_terms,
            c_obj=C_obj,
            a_terms=len(A_terms),
            a_td_terms=A_td_terms,
            spline_count=spline_count,
            config=config,
            sparse=False,
            use_secular=use_secular,
            use_openmp=options.use_openmp,
            omp_thresh=qset.openmp_thresh if qset.has_openmp else None,
            omp_threads=options.num_cpus,
            atol=tol)

        cgen.generate(config.tdname + ".pyx")
        code = compile('from ' + config.tdname + ' import cy_td_ode_rhs',
                       '<string>', 'exec')
        exec(code, globals())
        config.tdfunc = cy_td_ode_rhs

    initial_vector = mat2vec(rho0.full()).ravel()

    _ode = scipy.integrate.ode(config.tdfunc)
    code = compile('_ode.set_f_params(' + parameter_string + ')', '<string>',
                   'exec')
    _ode.set_integrator('zvode',
                        method=options.method,
                        order=options.order,
                        atol=options.atol,
                        rtol=options.rtol,
                        nsteps=options.nsteps,
                        first_step=options.first_step,
                        min_step=options.min_step,
                        max_step=options.max_step)
    _ode.set_initial_value(initial_vector, tlist[0])
    exec(code, locals())

    #
    # prepare output array
    #
    n_tsteps = len(tlist)
    e_sops_data = []

    output = Result()
    output.solver = "brmesolve"
    output.times = tlist

    if options.store_states:
        output.states = []

    if isinstance(e_ops, types.FunctionType):
        n_expt_op = 0
        expt_callback = True

    elif isinstance(e_ops, list):
        n_expt_op = len(e_ops)
        expt_callback = False

        if n_expt_op == 0:
            # fall back on storing states
            output.states = []
            options.store_states = True
        else:
            output.expect = []
            output.num_expect = n_expt_op
            for op in e_ops:
                e_sops_data.append(spre(op).data)
                if op.isherm:
                    output.expect.append(np.zeros(n_tsteps))
                else:
                    output.expect.append(np.zeros(n_tsteps, dtype=complex))

    else:
        raise TypeError("Expectation parameter must be a list or a function")

    #
    # start evolution
    #
    progress_bar.start(n_tsteps)

    rho = Qobj(rho0)

    dt = np.diff(tlist)
    for t_idx, t in enumerate(tlist):
        progress_bar.update(t_idx)

        if not _ode.successful():
            raise Exception("ODE integration error: Try to increase "
                            "the allowed number of substeps by increasing "
                            "the nsteps parameter in the Options class.")

        if options.store_states or expt_callback:
            rho.data = dense2D_to_fastcsr_fmode(vec2mat(_ode.y), rho.shape[0],
                                                rho.shape[1])

            if options.store_states:
                output.states.append(Qobj(rho, isherm=True))

            if expt_callback:
                # use callback method
                e_ops(t, rho)

        for m in range(n_expt_op):
            if output.expect[m].dtype == complex:
                output.expect[m][t_idx] = expect_rho_vec(
                    e_sops_data[m], _ode.y, 0)
            else:
                output.expect[m][t_idx] = expect_rho_vec(
                    e_sops_data[m], _ode.y, 1)

        if t_idx < n_tsteps - 1:
            _ode.integrate(_ode.t + dt[t_idx])

    progress_bar.finished()

    if (not options.rhs_reuse) and (config.tdname is not None):
        _cython_build_cleanup(config.tdname)

    if options.store_final_state:
        rho.data = dense2D_to_fastcsr_fmode(vec2mat(_ode.y), rho.shape[0],
                                            rho.shape[1])
        output.final_state = Qobj(rho, dims=rho0.dims, isherm=True)

    return output
Example #2
0
def _td_brmesolve(H, psi0, tlist, a_ops=[], e_ops=[], c_ops=[], args={},
                 use_secular=True, sec_cutoff=0.1,
                 tol=qset.atol, options=None, 
                 progress_bar=None,_safe_mode=True,
                 verbose=False,
                 _prep_time=0):
    
    if isket(psi0):
        rho0 = ket2dm(psi0)
    else:
        rho0 = psi0
    nrows = rho0.shape[0]
    
    H_terms = []
    H_td_terms = []
    H_obj = []
    A_terms = []
    A_td_terms = []
    C_terms = []
    C_td_terms = []
    CA_obj = []
    spline_count = [0,0]
    coupled_ops = []
    coupled_lengths = []
    coupled_spectra = []
    
    if isinstance(H, Qobj):
        H_terms.append(H.full('f'))
        H_td_terms.append('1')
    else: 
        for kk, h in enumerate(H):
            if isinstance(h, Qobj):
                H_terms.append(h.full('f'))
                H_td_terms.append('1')
            elif isinstance(h, list):
                H_terms.append(h[0].full('f'))
                if isinstance(h[1], Cubic_Spline):
                    H_obj.append(h[1].coeffs)
                    spline_count[0] += 1
                H_td_terms.append(h[1])
            else:
                raise Exception('Invalid Hamiltonian specification.')
    
            
    for kk, c in enumerate(c_ops):
        if isinstance(c, Qobj):
            C_terms.append(c.full('f'))
            C_td_terms.append('1')
        elif isinstance(c, list):
            C_terms.append(c[0].full('f'))
            if isinstance(c[1], Cubic_Spline):
                CA_obj.append(c[1].coeffs)
                spline_count[0] += 1
            C_td_terms.append(c[1])
        else:
            raise Exception('Invalid collapse operator specification.')
            
    coupled_offset = 0
    for kk, a in enumerate(a_ops):
        if isinstance(a, list):
            if isinstance(a[0], Qobj):
                A_terms.append(a[0].full('f'))
                A_td_terms.append(a[1])
                if isinstance(a[1], tuple):
                    if not len(a[1])==2:
                       raise Exception('Tuple must be len=2.')
                    if isinstance(a[1][0],Cubic_Spline):
                        spline_count[1] += 1
                    if isinstance(a[1][1],Cubic_Spline):
                        spline_count[1] += 1
            elif isinstance(a[0], tuple):
                if not isinstance(a[1], tuple):
                    raise Exception('Invalid bath-coupling specification.')
                if (len(a[0])+1) != len(a[1]):
                    raise Exception('BR a_ops tuple lengths not compatible.')
                
                coupled_ops.append(kk+coupled_offset)
                coupled_lengths.append(len(a[0]))
                coupled_spectra.append(a[1][0])
                coupled_offset += len(a[0])-1
                if isinstance(a[1][0],Cubic_Spline):
                    spline_count[1] += 1
                
                for nn, _a in enumerate(a[0]):
                    A_terms.append(_a.full('f'))
                    A_td_terms.append(a[1][nn+1])
                    if isinstance(a[1][nn+1],Cubic_Spline):
                        CA_obj.append(a[1][nn+1].coeffs)
                        spline_count[1] += 1
                                
        else:
            raise Exception('Invalid bath-coupling specification.')
            
    
    string_list = []
    for kk,_ in enumerate(H_td_terms):
        string_list.append("H_terms[{0}]".format(kk))
    for kk,_ in enumerate(H_obj):
        string_list.append("H_obj[{0}]".format(kk))
    for kk,_ in enumerate(C_td_terms):
        string_list.append("C_terms[{0}]".format(kk))
    for kk,_ in enumerate(CA_obj):
        string_list.append("CA_obj[{0}]".format(kk))
    for kk,_ in enumerate(A_td_terms):
        string_list.append("A_terms[{0}]".format(kk))
    #Add nrows to parameters
    string_list.append('nrows')
    for name, value in args.items():
        if isinstance(value, np.ndarray):
            raise TypeError('NumPy arrays not valid args for BR solver.')
        else:
            string_list.append(str(value))
    parameter_string = ",".join(string_list)
    
    if verbose:
        print('BR prep time:', time.time()-_prep_time)
    #
    # generate and compile new cython code if necessary
    #
    if not options.rhs_reuse or config.tdfunc is None:
        if options.rhs_filename is None:
            config.tdname = "rhs" + str(os.getpid()) + str(config.cgen_num)
        else:
            config.tdname = opt.rhs_filename
        if verbose:
            _st = time.time()
        cgen = BR_Codegen(h_terms=len(H_terms), 
                    h_td_terms=H_td_terms, h_obj=H_obj,
                    c_terms=len(C_terms), 
                    c_td_terms=C_td_terms, c_obj=CA_obj,
                    a_terms=len(A_terms), a_td_terms=A_td_terms,
                    spline_count=spline_count,
                    coupled_ops = coupled_ops,
                    coupled_lengths = coupled_lengths,
                    coupled_spectra = coupled_spectra,
                    config=config, sparse=False,
                    use_secular = use_secular,
                    sec_cutoff = sec_cutoff,
                    args=args,
                    use_openmp=options.use_openmp, 
                    omp_thresh=qset.openmp_thresh if qset.has_openmp else None,
                    omp_threads=options.num_cpus, 
                    atol=tol)
        
        cgen.generate(config.tdname + ".pyx")
        code = compile('from ' + config.tdname + ' import cy_td_ode_rhs',
                       '<string>', 'exec')
        exec(code, globals())
        config.tdfunc = cy_td_ode_rhs
        if verbose:
            print('BR compile time:', time.time()-_st)
    initial_vector = mat2vec(rho0.full()).ravel()
    
    _ode = scipy.integrate.ode(config.tdfunc)
    code = compile('_ode.set_f_params(' + parameter_string + ')',
                    '<string>', 'exec')
    _ode.set_integrator('zvode', method=options.method, 
                    order=options.order, atol=options.atol, 
                    rtol=options.rtol, nsteps=options.nsteps,
                    first_step=options.first_step, 
                    min_step=options.min_step,
                    max_step=options.max_step)
    _ode.set_initial_value(initial_vector, tlist[0])
    exec(code, locals())
    
    #
    # prepare output array
    #
    n_tsteps = len(tlist)
    e_sops_data = []

    output = Result()
    output.solver = "brmesolve"
    output.times = tlist

    if options.store_states:
        output.states = []

    if isinstance(e_ops, types.FunctionType):
        n_expt_op = 0
        expt_callback = True

    elif isinstance(e_ops, list):
        n_expt_op = len(e_ops)
        expt_callback = False

        if n_expt_op == 0:
            # fall back on storing states
            output.states = []
            options.store_states = True
        else:
            output.expect = []
            output.num_expect = n_expt_op
            for op in e_ops:
                e_sops_data.append(spre(op).data)
                if op.isherm:
                    output.expect.append(np.zeros(n_tsteps))
                else:
                    output.expect.append(np.zeros(n_tsteps, dtype=complex))

    else:
        raise TypeError("Expectation parameter must be a list or a function")

    #
    # start evolution
    #
    if type(progress_bar)==BaseProgressBar and verbose:
        _run_time = time.time()
    
    progress_bar.start(n_tsteps)

    rho = Qobj(rho0)

    dt = np.diff(tlist)
    for t_idx, t in enumerate(tlist):
        progress_bar.update(t_idx)

        if not _ode.successful():
            raise Exception("ODE integration error: Try to increase "
                            "the allowed number of substeps by increasing "
                            "the nsteps parameter in the Options class.")

        if options.store_states or expt_callback:
            rho.data = dense2D_to_fastcsr_fmode(vec2mat(_ode.y), rho.shape[0], rho.shape[1])

            if options.store_states:
                output.states.append(Qobj(rho, isherm=True))

            if expt_callback:
                # use callback method
                e_ops(t, rho)

        for m in range(n_expt_op):
            if output.expect[m].dtype == complex:
                output.expect[m][t_idx] = expect_rho_vec(e_sops_data[m],
                                                         _ode.y, 0)
            else:
                output.expect[m][t_idx] = expect_rho_vec(e_sops_data[m],
                                                         _ode.y, 1)

        if t_idx < n_tsteps - 1:
            _ode.integrate(_ode.t + dt[t_idx])

    progress_bar.finished()
    
    if type(progress_bar)==BaseProgressBar and verbose:
        print('BR runtime:', time.time()-_run_time)

    if (not options.rhs_reuse) and (config.tdname is not None):
        _cython_build_cleanup(config.tdname)
    
    if options.store_final_state:
        rho.data = dense2D_to_fastcsr_fmode(vec2mat(_ode.y), rho.shape[0], rho.shape[1])
        output.final_state = Qobj(rho, dims=rho0.dims, isherm=True)

    return output