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Python Result.solver方法代码示例

本文整理汇总了Python中qutip.solver.Result.solver方法的典型用法代码示例。如果您正苦于以下问题:Python Result.solver方法的具体用法?Python Result.solver怎么用?Python Result.solver使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在qutip.solver.Result的用法示例。


在下文中一共展示了Result.solver方法的15个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: _smepdpsolve_generic

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _smepdpsolve_generic(sso, options, progress_bar):
    """
    For internal use. See smepdpsolve.
    """
    if debug:
        logger.debug(inspect.stack()[0][3])

    N_store = len(sso.times)
    N_substeps = sso.nsubsteps
    dt = (sso.times[1] - sso.times[0]) / N_substeps
    nt = sso.ntraj

    data = Result()
    data.solver = "smepdpsolve"
    data.times = sso.times
    data.expect = np.zeros((len(sso.e_ops), N_store), dtype=complex)
    data.jump_times = []
    data.jump_op_idx = []

    # Liouvillian for the deterministic part.
    # needs to be modified for TD systems
    L = liouvillian(sso.H, sso.c_ops)

    progress_bar.start(sso.ntraj)

    for n in range(sso.ntraj):
        progress_bar.update(n)
        rho_t = mat2vec(sso.rho0.full()).ravel()

        states_list, jump_times, jump_op_idx = \
            _smepdpsolve_single_trajectory(data, L, dt, sso.times,
                                           N_store, N_substeps,
                                           rho_t, sso.rho0.dims,
                                           sso.c_ops, sso.e_ops)

        data.states.append(states_list)
        data.jump_times.append(jump_times)
        data.jump_op_idx.append(jump_op_idx)

    progress_bar.finished()

    # average density matrices
    if options.average_states and np.any(data.states):
        data.states = [sum([data.states[m][n] for m in range(nt)]).unit()
                       for n in range(len(data.times))]

    # average
    data.expect = data.expect / sso.ntraj

    # standard error
    if nt > 1:
        data.se = (data.ss - nt * (data.expect ** 2)) / (nt * (nt - 1))
    else:
        data.se = None

    return data
开发者ID:sahmed95,项目名称:qutip,代码行数:58,代码来源:pdpsolve.py

示例2: solve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
 def solve(self, rho0, tlist, options=None):
     """
     Solve the ODE for the evolution of diagonal states and Hamiltonians.
     """
     if options is None:
         options = Options()
     output = Result()
     output.solver = "pisolve"
     output.times = tlist
     output.states = []
     output.states.append(Qobj(rho0))
     rhs_generate = lambda y, tt, M: M.dot(y)
     rho0_flat = np.diag(np.real(rho0.full()))
     L = self.coefficient_matrix()
     rho_t = odeint(rhs_generate, rho0_flat, tlist, args=(L,))
     for r in rho_t[1:]:
         diag = np.diag(r)
         output.states.append(Qobj(diag))
     return output
开发者ID:jenshnielsen,项目名称:qutip,代码行数:21,代码来源:piqs.py

示例3: floquet_markov_mesolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def floquet_markov_mesolve(R, ekets, rho0, tlist, e_ops, f_modes_table=None,
                           options=None, floquet_basis=True):
    """
    Solve the dynamics for the system using the Floquet-Markov master equation.
    """

    if options is None:
        opt = Options()
    else:
        opt = options

    if opt.tidy:
        R.tidyup()

    #
    # check initial state
    #
    if isket(rho0):
        # Got a wave function as initial state: convert to density matrix.
        rho0 = ket2dm(rho0)

    #
    # prepare output array
    #
    n_tsteps = len(tlist)
    dt = tlist[1] - tlist[0]

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

    if isinstance(e_ops, 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:
            output.states = []
        else:
            if not f_modes_table:
                raise TypeError("The Floquet mode table has to be provided " +
                                "when requesting expectation values.")

            output.expect = []
            output.num_expect = n_expt_op
            for op in e_ops:
                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")

    #
    # transform the initial density matrix to the eigenbasis: from
    # computational basis to the floquet basis
    #
    if ekets is not None:
        rho0 = rho0.transform(ekets)

    #
    # setup integrator
    #
    initial_vector = mat2vec(rho0.full())
    r = scipy.integrate.ode(cy_ode_rhs)
    r.set_f_params(R.data.data, R.data.indices, R.data.indptr)
    r.set_integrator('zvode', method=opt.method, order=opt.order,
                     atol=opt.atol, rtol=opt.rtol, max_step=opt.max_step)
    r.set_initial_value(initial_vector, tlist[0])

    #
    # start evolution
    #
    rho = Qobj(rho0)

    t_idx = 0
    for t in tlist:
        if not r.successful():
            break

        rho.data = vec2mat(r.y)

        if expt_callback:
            # use callback method
            if floquet_basis:
                e_ops(t, Qobj(rho))
            else:
                f_modes_table_t, T = f_modes_table
                f_modes_t = floquet_modes_t_lookup(f_modes_table_t, t, T)
                e_ops(t, Qobj(rho).transform(f_modes_t, True))
        else:
            # calculate all the expectation values, or output rho if
            # no operators
            if n_expt_op == 0:
                if floquet_basis:
#.........这里部分代码省略.........
开发者ID:Marata459,项目名称:qutip,代码行数:103,代码来源:floquet.py

示例4: fsesolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def fsesolve(H, psi0, tlist, e_ops=[], T=None, args={}, Tsteps=100):
    """
    Solve the Schrodinger equation using the Floquet formalism.

    Parameters
    ----------

    H : :class:`qutip.qobj.Qobj`
        System Hamiltonian, time-dependent with period `T`.

    psi0 : :class:`qutip.qobj`
        Initial state vector (ket).

    tlist : *list* / *array*
        list of times for :math:`t`.

    e_ops : list of :class:`qutip.qobj` / callback function
        list of operators for which to evaluate expectation values. If this
        list is empty, the state vectors for each time in `tlist` will be
        returned instead of expectation values.

    T : float
        The period of the time-dependence of the hamiltonian.

    args : dictionary
        Dictionary with variables required to evaluate H.

    Tsteps : integer
        The number of time steps in one driving period for which to
        precalculate the Floquet modes. `Tsteps` should be an even number.

    Returns
    -------

    output : :class:`qutip.solver.Result`

        An instance of the class :class:`qutip.solver.Result`, which
        contains either an *array* of expectation values or an array of
        state vectors, for the times specified by `tlist`.
    """

    if not T:
        # assume that tlist span exactly one period of the driving
        T = tlist[-1]

    # find the floquet modes for the time-dependent hamiltonian
    f_modes_0, f_energies = floquet_modes(H, T, args)

    # calculate the wavefunctions using the from the floquet modes
    f_modes_table_t = floquet_modes_table(f_modes_0, f_energies,
                                          np.linspace(0, T, Tsteps + 1),
                                          H, T, args)

    # setup Result for storing the results
    output = Result()
    output.times = tlist
    output.solver = "fsesolve"

    if isinstance(e_ops, FunctionType):
        output.num_expect = 0
        expt_callback = True

    elif isinstance(e_ops, list):

        output.num_expect = len(e_ops)
        expt_callback = False

        if output.num_expect == 0:
            output.states = []
        else:
            output.expect = []
            for op in e_ops:
                if op.isherm:
                    output.expect.append(np.zeros(len(tlist)))
                else:
                    output.expect.append(np.zeros(len(tlist), dtype=complex))

    else:
        raise TypeError("e_ops must be a list Qobj or a callback function")

    psi0_fb = psi0.transform(f_modes_0)
    for t_idx, t in enumerate(tlist):
        f_modes_t = floquet_modes_t_lookup(f_modes_table_t, t, T)
        f_states_t = floquet_states(f_modes_t, f_energies, t)
        psi_t = psi0_fb.transform(f_states_t, True)

        if expt_callback:
            # use callback method
            e_ops(t, psi_t)
        else:
            # calculate all the expectation values, or output psi if
            # no expectation value operators where defined
            if output.num_expect == 0:
                output.states.append(Qobj(psi_t))
            else:
                for e_idx, e in enumerate(e_ops):
                    output.expect[e_idx][t_idx] = expect(e, psi_t)

    return output
开发者ID:Marata459,项目名称:qutip,代码行数:101,代码来源:floquet.py

示例5: _generic_ode_solve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _generic_ode_solve(r, rho0, tlist, e_ops, opt, progress_bar):
    """
    Internal function for solving ME. Solve an ODE which solver parameters
    already setup (r). Calculate the required expectation values or invoke
    callback function at each time step.
    """

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

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

    if opt.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 = []
            opt.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 and rho0.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 r.successful():
            break

        if opt.store_states or expt_callback:
            rho.data = vec2mat(r.y)

            if opt.store_states:
                output.states.append(Qobj(rho))

            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], r.y, 0)
            else:
                output.expect[m][t_idx] = expect_rho_vec(e_sops_data[m], r.y, 1)

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

    progress_bar.finished()

    if not opt.rhs_reuse and config.tdname is not None:
        try:
            os.remove(config.tdname + ".pyx")
        except:
            pass

    if opt.store_final_state:
        rho.data = vec2mat(r.y)
        output.final_state = Qobj(rho)

    return output
开发者ID:wa4557,项目名称:qutip,代码行数:94,代码来源:mesolve.py

示例6: brmesolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def brmesolve(H, psi0, tlist, a_ops, e_ops=[], spectra_cb=[], c_ops=[],
              args={}, options=Options()):
    """
    Solve the dynamics for a system using the Bloch-Redfield master equation.

    .. note::

        This solver does not currently support time-dependent Hamiltonians.

    Parameters
    ----------

    H : :class:`qutip.Qobj`
        System Hamiltonian.

    rho0 / psi0: :class:`qutip.Qobj`
        Initial density matrix or state vector (ket).

    tlist : *list* / *array*
        List of times for :math:`t`.

    a_ops : list of :class:`qutip.qobj`
        List of system operators that couple to bath degrees of freedom.

    e_ops : list of :class:`qutip.qobj` / callback function
        List of operators for which to evaluate expectation values.

    c_ops : list of :class:`qutip.qobj`
        List of system collapse operators.

    args : *dictionary*
        Placeholder for future implementation, kept for API consistency.

    options : :class:`qutip.solver.Options`
        Options for the solver.

    Returns
    -------

    result: :class:`qutip.solver.Result`

        An instance of the class :class:`qutip.solver.Result`, which contains
        either an array of expectation values, for operators given in e_ops,
        or a list of states for the times specified by `tlist`.
    """

    if not spectra_cb:
        # default to infinite temperature white noise
        spectra_cb = [lambda w: 1.0 for _ in a_ops]

    R, ekets = bloch_redfield_tensor(H, a_ops, spectra_cb, c_ops)

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

    results = bloch_redfield_solve(R, ekets, psi0, tlist, e_ops, options)

    if e_ops:
        output.expect = results
    else:
        output.states = results

    return output
开发者ID:JonathanUlm,项目名称:qutip,代码行数:66,代码来源:bloch_redfield.py

示例7: mcsolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def mcsolve(H, psi0, tlist, c_ops, e_ops, ntraj=None,
            args={}, options=None, progress_bar=True,
            map_func=None, map_kwargs=None):
    """Monte Carlo evolution of a state vector :math:`|\psi \\rangle` for a
    given Hamiltonian and sets of collapse operators, and possibly, operators
    for calculating expectation values. Options for the underlying ODE solver
    are given by the Options class.

    mcsolve supports time-dependent Hamiltonians and collapse operators using
    either Python functions of strings to represent time-dependent
    coefficients. Note that, the system Hamiltonian MUST have at least one
    constant term.

    As an example of a time-dependent problem, consider a Hamiltonian with two
    terms ``H0`` and ``H1``, where ``H1`` is time-dependent with coefficient
    ``sin(w*t)``, and collapse operators ``C0`` and ``C1``, where ``C1`` is
    time-dependent with coeffcient ``exp(-a*t)``.  Here, w and a are constant
    arguments with values ``W`` and ``A``.

    Using the Python function time-dependent format requires two Python
    functions, one for each collapse coefficient. Therefore, this problem could
    be expressed as::

        def H1_coeff(t,args):
            return sin(args['w']*t)

        def C1_coeff(t,args):
            return exp(-args['a']*t)

        H = [H0, [H1, H1_coeff]]

        c_ops = [C0, [C1, C1_coeff]]

        args={'a': A, 'w': W}

    or in String (Cython) format we could write::

        H = [H0, [H1, 'sin(w*t)']]

        c_ops = [C0, [C1, 'exp(-a*t)']]

        args={'a': A, 'w': W}

    Constant terms are preferably placed first in the Hamiltonian and collapse
    operator lists.

    Parameters
    ----------
    H : :class:`qutip.Qobj`
        System Hamiltonian.

    psi0 : :class:`qutip.Qobj`
        Initial state vector

    tlist : array_like
        Times at which results are recorded.

    ntraj : int
        Number of trajectories to run.

    c_ops : array_like
        single collapse operator or ``list`` or ``array`` of collapse
        operators.

    e_ops : array_like
        single operator or ``list`` or ``array`` of operators for calculating
        expectation values.

    args : dict
        Arguments for time-dependent Hamiltonian and collapse operator terms.

    options : Options
        Instance of ODE solver options.

    progress_bar: BaseProgressBar
        Optional instance of BaseProgressBar, or a subclass thereof, for
        showing the progress of the simulation. Set to None to disable the
        progress bar.

    map_func: function
        A map function for managing the calls to the single-trajactory solver.

    map_kwargs: dictionary
        Optional keyword arguments to the map_func function.

    Returns
    -------
    results : :class:`qutip.solver.Result`
        Object storing all results from the simulation.

    .. note::

        It is possible to reuse the random number seeds from a previous run
        of the mcsolver by passing the output Result object seeds via the
        Options class, i.e. Options(seeds=prev_result.seeds).
    """

    if debug:
        print(inspect.stack()[0][3])

#.........这里部分代码省略.........
开发者ID:mil52603,项目名称:qutip,代码行数:103,代码来源:mcsolve.py

示例8: _generic_ode_solve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _generic_ode_solve(r, rho0, tlist, e_ops, opt, progress_bar):
    """
    Internal function for solving ME. Solve an ODE which solver parameters
    already setup (r). Calculate the required expectation values or invoke
    callback function at each time step.
    """

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

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

    if opt.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 = []
            opt.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 and rho0.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 r.successful():
            raise Exception("ODE integration error: Try to increase "
                            "the allowed number of substeps by increasing "
                            "the nsteps parameter in the Options class.")

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

            if opt.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],
                                                         r.y, 0)
            else:
                output.expect[m][t_idx] = expect_rho_vec(e_sops_data[m],
                                                         r.y, 1)

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

    progress_bar.finished()

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

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

    return output
开发者ID:anubhavvardhan,项目名称:qutip,代码行数:95,代码来源:mesolve.py

示例9: _ssepdpsolve_generic

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _ssepdpsolve_generic(sso, options, progress_bar):
    """
    For internal use. See ssepdpsolve.
    """
    if debug:
        logger.debug(inspect.stack()[0][3])

    N_store = len(sso.times)
    N_substeps = sso.nsubsteps
    dt = (sso.times[1] - sso.times[0]) / N_substeps
    nt = sso.ntraj

    data = Result()
    data.solver = "sepdpsolve"
    data.times = sso.tlist
    data.expect = np.zeros((len(sso.e_ops), N_store), dtype=complex)
    data.ss = np.zeros((len(sso.e_ops), N_store), dtype=complex)
    data.jump_times = []
    data.jump_op_idx = []

    # effective hamiltonian for deterministic part
    Heff = sso.H
    for c in sso.c_ops:
        Heff += -0.5j * c.dag() * c

    progress_bar.start(sso.ntraj)
    for n in range(sso.ntraj):
        progress_bar.update(n)
        psi_t = sso.state0.full().ravel()

        states_list, jump_times, jump_op_idx = \
            _ssepdpsolve_single_trajectory(data, Heff, dt, sso.times,
                                           N_store, N_substeps,
                                           psi_t, sso.state0.dims,
                                           sso.c_ops, sso.e_ops)

        data.states.append(states_list)
        data.jump_times.append(jump_times)
        data.jump_op_idx.append(jump_op_idx)

    progress_bar.finished()

    # average density matrices
    if options.average_states and np.any(data.states):
        data.states = [sum([data.states[m][n] for m in range(nt)]).unit()
                       for n in range(len(data.times))]

    # average
    data.expect = data.expect / nt

    # standard error
    if nt > 1:
        data.se = (data.ss - nt * (data.expect ** 2)) / (nt * (nt - 1))
    else:
        data.se = None

    # convert complex data to real if hermitian
    data.expect = [np.real(data.expect[n, :])
                   if e.isherm else data.expect[n, :]
                   for n, e in enumerate(sso.e_ops)]

    return data
开发者ID:sahmed95,项目名称:qutip,代码行数:64,代码来源:pdpsolve.py

示例10: _td_brmesolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]

#.........这里部分代码省略.........
                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, 
开发者ID:ajgpitch,项目名称:qutip,代码行数:70,代码来源:bloch_redfield.py

示例11: run

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
    def run(self, rho0, tlist):
        """
        Function to solve for an open quantum system using the
        HEOM model.

        Parameters
        ----------
        rho0 : Qobj
            Initial state (density matrix) of the system.

        tlist : list
            Time over which system evolves.

        Returns
        -------
        results : :class:`qutip.solver.Result`
            Object storing all results from the simulation.
        """

        start_run = timeit.default_timer()

        sup_dim = self._sup_dim
        stats = self.stats
        r = self._ode

        if not self._configured:
            raise RuntimeError("Solver must be configured before it is run")
        if stats:
            ss_conf = stats.sections.get('config')
            if ss_conf is None:
                raise RuntimeError("No config section for solver stats")
            ss_run = stats.sections.get('run')
            if ss_run is None:
                ss_run = stats.add_section('run')

        # Set up terms of the matsubara and tanimura boundaries
        output = Result()
        output.solver = "hsolve"
        output.times = tlist
        output.states = []

        if stats: start_init = timeit.default_timer()
        output.states.append(Qobj(rho0))
        rho0_flat = rho0.full().ravel('F') # Using 'F' effectively transposes
        rho0_he = np.zeros([sup_dim*self._N_he], dtype=complex)
        rho0_he[:sup_dim] = rho0_flat
        r.set_initial_value(rho0_he, tlist[0])

        if stats:
            stats.add_timing('initialize',
                             timeit.default_timer() - start_init, ss_run)
            start_integ = timeit.default_timer()

        dt = np.diff(tlist)
        n_tsteps = len(tlist)
        for t_idx, t in enumerate(tlist):
            if t_idx < n_tsteps - 1:
                r.integrate(r.t + dt[t_idx])
                rho = Qobj(r.y[:sup_dim].reshape(rho0.shape), dims=rho0.dims)
                output.states.append(rho)

        if stats:
            time_now = timeit.default_timer()
            stats.add_timing('integrate',
                             time_now - start_integ, ss_run)
            if ss_run.total_time is None:
                ss_run.total_time = time_now - start_run
            else:
                ss_run.total_time += time_now - start_run
            stats.total_time = ss_conf.total_time + ss_run.total_time

        return output
开发者ID:MichalKononenko,项目名称:qutip,代码行数:74,代码来源:heom.py

示例12: _generic_ode_solve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _generic_ode_solve(r, psi0, tlist, e_ops, opt, progress_bar, dims=None):
    """
    Internal function for solving ODEs.
    """

    #
    # prepare output array
    #
    n_tsteps = len(tlist)
    output = Result()
    output.solver = "sesolve"
    output.times = tlist

    if psi0.isunitary:
        oper_evo = True
        oper_n = dims[0][0]
        norm_dim_factor = np.sqrt(oper_n)
    else:
        oper_evo = False
        norm_dim_factor = 1.0

    if opt.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:
            # fallback on storing states
            output.states = []
            opt.store_states = True
        else:
            output.expect = []
            output.num_expect = n_expt_op
            for op in e_ops:
                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")

    def get_curr_state_data():
        if oper_evo:
            return vec2mat(r.y)
        else:
            return r.y

    #
    # start evolution
    #
    progress_bar.start(n_tsteps)

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

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

        # get the current state / oper data if needed
        cdata = None
        if opt.store_states or opt.normalize_output or n_expt_op > 0:
            cdata = get_curr_state_data()

        if opt.normalize_output:
            # cdata *= _get_norm_factor(cdata, oper_evo)
            cdata *= norm_dim_factor / la_norm(cdata)
            if oper_evo:
                r.set_initial_value(cdata.ravel('F'), r.t)
            else:
                r.set_initial_value(cdata, r.t)

        if opt.store_states:
            output.states.append(Qobj(cdata, dims=dims))

        if expt_callback:
            # use callback method
            e_ops(t, Qobj(cdata, dims=dims))

        for m in range(n_expt_op):
            output.expect[m][t_idx] = cy_expect_psi(e_ops[m].data,
                                                    cdata, e_ops[m].isherm)

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

    progress_bar.finished()

    if not opt.rhs_reuse and config.tdname is not None:
        try:
            os.remove(config.tdname + ".pyx")
        except:
#.........这里部分代码省略.........
开发者ID:ajgpitch,项目名称:qutip,代码行数:103,代码来源:sesolve.py

示例13: _generic_ode_solve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def _generic_ode_solve(r, psi0, tlist, e_ops, opt, progress_bar,
                       state_norm_func=None, dims=None):
    """
    Internal function for solving ODEs.
    """

    #
    # prepare output array
    #
    n_tsteps = len(tlist)
    output = Result()
    output.solver = "sesolve"
    output.times = tlist

    if opt.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:
            # fallback on storing states
            output.states = []
            opt.store_states = True
        else:
            output.expect = []
            output.num_expect = n_expt_op
            for op in e_ops:
                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)

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

        if not r.successful():
            break

        if state_norm_func:
            data = r.y / state_norm_func(r.y)
            r.set_initial_value(data, r.t)

        if opt.store_states:
            output.states.append(Qobj(r.y, dims=dims))

        if expt_callback:
            # use callback method
            e_ops(t, Qobj(r.y, dims=psi0.dims))

        for m in range(n_expt_op):
            output.expect[m][t_idx] = cy_expect_psi(e_ops[m].data,
                                                    r.y, e_ops[m].isherm)

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

    progress_bar.finished()

    if not opt.rhs_reuse and config.tdname is not None:
        try:
            os.remove(config.tdname + ".pyx")
        except:
            pass

    if opt.store_final_state:
        output.final_state = Qobj(r.y)

    return output
开发者ID:Marata459,项目名称:qutip,代码行数:85,代码来源:sesolve.py

示例14: mcsolve

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def mcsolve(H, psi0, tlist, c_ops, e_ops, ntraj=None, args={}, options=Options()):
    """Monte-Carlo evolution of a state vector :math:`|\psi \\rangle` for a
    given Hamiltonian and sets of collapse operators, and possibly, operators
    for calculating expectation values. Options for the underlying ODE solver
    are given by the Options class.

    mcsolve supports time-dependent Hamiltonians and collapse operators using
    either Python functions of strings to represent time-dependent
    coefficients. Note that, the system Hamiltonian MUST have at least one
    constant term.

    As an example of a time-dependent problem, consider a Hamiltonian with two
    terms ``H0`` and ``H1``, where ``H1`` is time-dependent with coefficient
    ``sin(w*t)``, and collapse operators ``C0`` and ``C1``, where ``C1`` is
    time-dependent with coeffcient ``exp(-a*t)``.  Here, w and a are constant
    arguments with values ``W`` and ``A``.

    Using the Python function time-dependent format requires two Python
    functions, one for each collapse coefficient. Therefore, this problem could
    be expressed as::

        def H1_coeff(t,args):
            return sin(args['w']*t)

        def C1_coeff(t,args):
            return exp(-args['a']*t)

        H=[H0,[H1,H1_coeff]]

        c_op_list=[C0,[C1,C1_coeff]]

        args={'a':A,'w':W}

    or in String (Cython) format we could write::

        H=[H0,[H1,'sin(w*t)']]

        c_op_list=[C0,[C1,'exp(-a*t)']]

        args={'a':A,'w':W}

    Constant terms are preferably placed first in the Hamiltonian and collapse
    operator lists.

    Parameters
    ----------
    H : qobj
        System Hamiltonian.
    psi0 : qobj
        Initial state vector
    tlist : array_like
        Times at which results are recorded.
    ntraj : int
        Number of trajectories to run.
    c_ops : array_like
        single collapse operator or ``list`` or ``array`` of collapse
        operators.
    e_ops : array_like
        single operator or ``list`` or ``array`` of operators for calculating
        expectation values.
    args : dict
        Arguments for time-dependent Hamiltonian and collapse operator terms.
    options : Options
        Instance of ODE solver options.

    Returns
    -------
    results : Result
        Object storing all results from simulation.

    """

    if debug:
        print(inspect.stack()[0][3])

    if ntraj is None:
        ntraj = options.ntraj

    if not psi0.isket:
        raise Exception("Initial state must be a state vector.")

    if isinstance(c_ops, Qobj):
        c_ops = [c_ops]

    if isinstance(e_ops, Qobj):
        e_ops = [e_ops]

    if isinstance(e_ops, dict):
        e_ops_dict = e_ops
        e_ops = [e for e in e_ops.values()]
    else:
        e_ops_dict = None

    config.options = options
    if isinstance(ntraj, list):
        config.progress_bar = TextProgressBar(max(ntraj))
    else:
        config.progress_bar = TextProgressBar(ntraj)

    # set num_cpus to the value given in qutip.settings if none in Options
#.........这里部分代码省略.........
开发者ID:ntezak,项目名称:qutip,代码行数:103,代码来源:mcsolve.py

示例15: mcsolve_f90

# 需要导入模块: from qutip.solver import Result [as 别名]
# 或者: from qutip.solver.Result import solver [as 别名]
def mcsolve_f90(H, psi0, tlist, c_ops, e_ops, ntraj=None,
                options=Options(), sparse_dms=True, serial=False,
                ptrace_sel=[], calc_entropy=False):
    """
    Monte-Carlo wave function solver with fortran 90 backend.
    Usage is identical to qutip.mcsolve, for problems without explicit
    time-dependence, and with some optional input:

    Parameters
    ----------
    H : qobj
        System Hamiltonian.
    psi0 : qobj
        Initial state vector
    tlist : array_like
        Times at which results are recorded.
    ntraj : int
        Number of trajectories to run.
    c_ops : array_like
        ``list`` or ``array`` of collapse operators.
    e_ops : array_like
        ``list`` or ``array`` of operators for calculating expectation values.
    options : Options
        Instance of solver options.
    sparse_dms : boolean
        If averaged density matrices are returned, they will be stored as
        sparse (Compressed Row Format) matrices during computation if
        sparse_dms = True (default), and dense matrices otherwise. Dense
        matrices might be preferable for smaller systems.
    serial : boolean
        If True (default is False) the solver will not make use of the
        multiprocessing module, and simply run in serial.
    ptrace_sel: list
        This optional argument specifies a list of components to keep when
        returning a partially traced density matrix. This can be convenient for
        large systems where memory becomes a problem, but you are only
        interested in parts of the density matrix.
    calc_entropy : boolean
        If ptrace_sel is specified, calc_entropy=True will have the solver
        return the averaged entropy over trajectories in results.entropy. This
        can be interpreted as a measure of entanglement. See Phys. Rev. Lett.
        93, 120408 (2004), Phys. Rev. A 86, 022310 (2012).

    Returns
    -------
    results : Result
        Object storing all results from simulation.

    """
    if ntraj is None:
        ntraj = options.ntraj

    if psi0.type != 'ket':
        raise Exception("Initial state must be a state vector.")
    config.options = options
    # set num_cpus to the value given in qutip.settings
    # if none in Options
    if not config.options.num_cpus:
        config.options.num_cpus = qutip.settings.num_cpus
    # set initial value data
    if options.tidy:
        config.psi0 = psi0.tidyup(options.atol).full()
    else:
        config.psi0 = psi0.full()
    config.psi0_dims = psi0.dims
    config.psi0_shape = psi0.shape
    # set general items
    config.tlist = tlist
    if isinstance(ntraj, (list, np.ndarray)):
        raise Exception("ntraj as list argument is not supported.")
    else:
        config.ntraj = ntraj
        # ntraj_list = [ntraj]
    # set norm finding constants
    config.norm_tol = options.norm_tol
    config.norm_steps = options.norm_steps

    if not options.rhs_reuse:
        config.soft_reset()
        # no time dependence
        config.tflag = 0
        # check for collapse operators
        if len(c_ops) > 0:
            config.cflag = 1
        else:
            config.cflag = 0
        # Configure data
        _mc_data_config(H, psi0, [], c_ops, [], [], e_ops, options, config)

    # Load Monte Carlo class
    mc = _MC_class()
    # Set solver type
    if (options.method == 'adams'):
        mc.mf = 10
    elif (options.method == 'bdf'):
        mc.mf = 22
    else:
        if debug:
            print('Unrecognized method for ode solver, using "adams".')
        mc.mf = 10
#.........这里部分代码省略.........
开发者ID:Marata459,项目名称:qutip,代码行数:103,代码来源:mcsolve_f90.py


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