mparray.py 文件源码

def _adapt_to_add_r(rightvec, compr_lten, tgt_lten):
    """Add one column to the right vector.

    :param rightvec: existing right vector
        It has two indices: `compr_mps_bond` and `tgt_mps_bond`

    :param compr_lten: Local tensor of the compressed MPS
    :param tgt_lten: Local tensor of the target MPS


    Construct R from [:ref:`Sch11 <Sch11>`, Fig. 27, p. 48]. See comments in
    :func:`_adapt_to_add_l()` for further details.

    .. todo:: Adapt tensor leg names.

    """
    rightvec_names = ('compr_bond', 'tgt_bond')
    compr_names = ('compr_left_bond', 'compr_phys', 'compr_right_bond')
    tgt_names = ('tgt_left_bond', 'tgt_phys', 'tgt_right_bond')
    rightvec = named_ndarray(rightvec, rightvec_names)
    compr_lten = named_ndarray(compr_lten, compr_names)
    tgt_lten = named_ndarray(tgt_lten, tgt_names)

    contract_compr_mps = (('compr_bond', 'compr_right_bond'),)
    rightvec = rightvec.tensordot(compr_lten, contract_compr_mps)

    contract_tgt_mps = (
        ('compr_phys', 'tgt_phys'),
        ('tgt_bond', 'tgt_right_bond'))
    rightvec = rightvec.tensordot(tgt_lten.conj(), contract_tgt_mps)
    rename = (
        ('compr_left_bond', 'compr_bond'),
        ('tgt_left_bond', 'tgt_bond'))
    rightvec = rightvec.rename(rename)

    rightvec = rightvec.to_array(rightvec_names)
    return rightvec