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Python Result.expect[m][i]方法代碼示例

本文整理匯總了Python中qutip.solver.Result.expect[m][i]方法的典型用法代碼示例。如果您正苦於以下問題:Python Result.expect[m][i]方法的具體用法?Python Result.expect[m][i]怎麽用?Python Result.expect[m][i]使用的例子?那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在qutip.solver.Result的用法示例。


在下文中一共展示了Result.expect[m][i]方法的1個代碼示例,這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚,您的評價將有助於係統推薦出更棒的Python代碼示例。

示例1: ttmsolve

# 需要導入模塊: from qutip.solver import Result [as 別名]
# 或者: from qutip.solver.Result import expect[m][i] [as 別名]

#.........這裏部分代碼省略.........
        Initial density matrix or state vector (ket).

    times : array_like
        list of times :math:`t_n` at which to compute :math:`\\rho(t_n)`.
        Must be uniformily spaced.

    e_ops : list of :class:`qutip.Qobj` / callback function
        single operator or list of operators for which to evaluate
        expectation values.

    learningtimes : array_like
        list of times :math:`t_k` for which we have knowledge of the dynamical
        maps :math:`E(t_k)`.

    tensors : array_like
        optional list of precomputed tensors :math:`T_k`

    kwargs : dictionary
        Optional keyword arguments. See
        :class:`qutip.nonmarkov.ttm.TTMSolverOptions`.

    Returns
    -------
    output: :class:`qutip.solver.Result`
        An instance of the class :class:`qutip.solver.Result`.
    """

    opt = TTMSolverOptions(dynmaps=dynmaps, times=times,
                           learningtimes=learningtimes, **kwargs)

    diff = None

    if isket(rho0):
        rho0 = ket2dm(rho0)

    output = Result()
    e_sops_data = []

    if callable(e_ops):
        n_expt_op = 0
        expt_callback = True

    else:
        try:
            tmp = e_ops[:]
            del tmp

            n_expt_op = len(e_ops)
            expt_callback = False

            if n_expt_op == 0:
                # fall back on storing states
                opt.store_states = True

            for op in e_ops:
                e_sops_data.append(spre(op).data)
                if op.isherm and rho0.isherm:
                    output.expect.append(np.zeros(len(times)))
                else:
                    output.expect.append(np.zeros(len(times), dtype=complex))
        except TypeError:
            raise TypeError("Argument 'e_ops' should be a callable or" +
                            "list-like.")

    if tensors is None:
        tensors, diff = _generatetensors(dynmaps, learningtimes, opt=opt)

    rho0vec = operator_to_vector(rho0)

    K = len(tensors)
    states = [rho0vec]
    for n in range(1, len(times)):
        states.append(None)
        for k in range(n):
            if n-k < K:
                states[-1] += tensors[n-k]*states[k]
    for i, r in enumerate(states):
        if opt.store_states or expt_callback:
            if r.type == 'operator-ket':
                states[i] = vector_to_operator(r)
            else:
                states[i] = r
            if expt_callback:
                # use callback method
                e_ops(times[i], states[i])
        for m in range(n_expt_op):
            if output.expect[m].dtype == complex:
                output.expect[m][i] = expect_rho_vec(e_sops_data[m], r, 0)
            else:
                output.expect[m][i] = expect_rho_vec(e_sops_data[m], r, 1)

    output.solver = "ttmsolve"
    output.times = times

    output.ttmconvergence = diff

    if opt.store_states:
        output.states = states

    return output
開發者ID:PhilipVinc,項目名稱:qutip,代碼行數:104,代碼來源:transfertensor.py


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