Python torch.log2方法代碼示例

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def __init__(self, output_size, scales, sampling_ratio):
        """
        Arguments:
            output_size (list[tuple[int]] or list[int]): output size for the pooled region
            scales (list[float]): scales for each Pooler
            sampling_ratio (int): sampling ratio for ROIAlign
        """
        super(Pooler, self).__init__()
        poolers = []
        for scale in scales:
            poolers.append(
                ROIAlign(
                    output_size, spatial_scale=scale, sampling_ratio=sampling_ratio
                )
            )
        self.poolers = nn.ModuleList(poolers)
        self.output_size = output_size
        # get the levels in the feature map by leveraging the fact that the network always
        # downsamples by a factor of 2 at each level.
        lvl_min = -torch.log2(torch.tensor(scales[0], dtype=torch.float32)).item()
        lvl_max = -torch.log2(torch.tensor(scales[-1], dtype=torch.float32)).item()
        self.map_levels = LevelMapper(lvl_min, lvl_max) 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def p2o(psf, shape):
    '''
    # psf: NxCxhxw
    # shape: [H,W]
    # otf: NxCxHxWx2
    '''
    otf = torch.zeros(psf.shape[:-2] + shape).type_as(psf)
    otf[...,:psf.shape[2],:psf.shape[3]].copy_(psf)
    for axis, axis_size in enumerate(psf.shape[2:]):
        otf = torch.roll(otf, -int(axis_size / 2), dims=axis+2)
    otf = torch.rfft(otf, 2, onesided=False)
    n_ops = torch.sum(torch.tensor(psf.shape).type_as(psf) * torch.log2(torch.tensor(psf.shape).type_as(psf)))
    otf[...,1][torch.abs(otf[...,1])<n_ops*2.22e-16] = torch.tensor(0).type_as(psf)
    return otf



# otf2psf: not sure where I got this one from. Maybe translated from Octave source code or whatever. It's just math. 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def p2o(psf, shape):
    '''
    Args:
        psf: NxCxhxw
        shape: [H,W]

    Returns:
        otf: NxCxHxWx2
    '''
    otf = torch.zeros(psf.shape[:-2] + shape).type_as(psf)
    otf[...,:psf.shape[2],:psf.shape[3]].copy_(psf)
    for axis, axis_size in enumerate(psf.shape[2:]):
        otf = torch.roll(otf, -int(axis_size / 2), dims=axis+2)
    otf = torch.rfft(otf, 2, onesided=False)
    n_ops = torch.sum(torch.tensor(psf.shape).type_as(psf) * torch.log2(torch.tensor(psf.shape).type_as(psf)))
    otf[...,1][torch.abs(otf[...,1])<n_ops*2.22e-16] = torch.tensor(0).type_as(psf)
    return otf 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def __init__(self, output_size, scales):
        """
        Arguments:
            output_size (list[tuple[int]] or list[int]): output size for the pooled region
            scales (list[float]): scales for each Pooler
            sampling_ratio (int): sampling ratio for ROIAlign
        """
        super(PyramidRROIAlign, self).__init__()
        poolers = []
        for scale in scales:
            poolers.append(
                RROIAlign(
                    output_size, spatial_scale=scale
                )
            )
        self.poolers = nn.ModuleList(poolers)
        self.output_size = output_size
        # get the levels in the feature map by leveraging the fact that the network always
        # downsamples by a factor of 2 at each level.
        lvl_min = -torch.log2(torch.tensor(scales[0], dtype=torch.float32)).item()
        lvl_max = -torch.log2(torch.tensor(scales[-1], dtype=torch.float32)).item()
        self.map_levels = LevelMapper(lvl_min, lvl_max) 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def test_LinQuant_forward(fsr, bit_width, inputs):
    op1 =  LogQuant(fsr=fsr, bit_width=bit_width, with_sign=False, lin_back=True)
 
    expected1 = torch.pow(torch.ones_like(inputs)*2, torch.clamp(torch.round(torch.log2(torch.abs(inputs))), fsr-2**bit_width ,fsr )) 

    assert equals(
        op1.apply(inputs),
        expected1
    )

    op2 =  LogQuant(fsr=fsr, bit_width=bit_width, with_sign=True, lin_back=True)
    expected2 = torch.sign(inputs)*torch.pow(torch.ones_like(inputs)*2, torch.clamp(torch.round(torch.log2(torch.abs(inputs))), fsr-2**bit_width ,fsr )) 

    assert equals(
        op2.apply(inputs),
        expected2
    ) 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def discounted_cumulative_gain(y         : torch.Tensor, 
                               k         : int = 10, 
                               gain_type : str = "exp2"):
    # Calculate cumulative gain
    y_partial = y[:k]
    if gain_type == "exp2":
        gains = torch.pow(y_partial, 2.0) - 1.0
    elif gain_type == "identity":
        gains = y_partial
    else:
        raise ValueError("gain type only allow \"exp2\" or \"identity\".")
    
    # Calculate discount
    ranges = torch.arange(1, k + 1, 1).float()
    discount = torch.log2(ranges + 1)
    dcg = torch.sum(torch.div(gains, discount))

    return dcg 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def log2(x, out=None):
    """
    log base 2, element-wise.

    Parameters
    ----------
    x : ht.DNDarray
        The value for which to compute the logarithm.
    out : ht.DNDarray or None, optional
        A location in which to store the results. If provided, it must have a broadcastable shape. If not provided
        or set to None, a fresh tensor is allocated.

    Returns
    -------
    logarithms : ht.DNDarray
        A tensor of the same shape as x, containing the positive logarithms of each element in this tensor.
        Negative input elements are returned as nan. If out was provided, logarithms is a reference to it.

    Examples
    --------
    >>> ht.log2(ht.arange(5))
    tensor([  -inf, 0.0000, 1.0000, 1.5850, 2.0000])
    """
    return operations.__local_op(torch.log2, x, out) 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def get_delta_gains(batch_stds, discount=False):
    '''
    Delta-gains w.r.t. pairwise swapping of the ideal ltr_adhoc
    :param batch_stds: the standard labels sorted in a descending order
    :return:
    '''
    batch_gains = torch.pow(2.0, batch_stds) - 1.0
    batch_g_diffs = torch.unsqueeze(batch_gains, dim=2) - torch.unsqueeze(batch_gains, dim=1)

    if discount:
        batch_std_ranks = torch.arange(batch_stds.size(1)).type(tensor)
        batch_dists = 1.0 / torch.log2(batch_std_ranks + 2.0)   # discount co-efficients
        batch_dists = torch.unsqueeze(batch_dists, dim=0)
        batch_dists_diffs = torch.unsqueeze(batch_dists, dim=2) - torch.unsqueeze(batch_dists, dim=1)
        batch_delta_gs = torch.abs(batch_g_diffs) * torch.abs(batch_dists_diffs)  # absolute changes w.r.t. pairwise swapping
    else:
        batch_delta_gs = torch.abs(batch_g_diffs)  # absolute delta gains w.r.t. pairwise swapping

    return batch_delta_gs 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def tor_discounted_cumu_gain_at_k(sorted_labels, cutoff, multi_level_rele=True):
    '''
    ICML-nDCG, which places stronger emphasis on retrieving relevant documents
    :param sorted_labels: ranked labels (either standard or predicted by a system) in the form of np array
    :param max_cutoff: the maximum rank position to be considered
    :param multi_lavel_rele: either the case of multi-level relevance or the case of listwise int-value, e.g., MQ2007-list
    :return: cumulative gains for each rank position
    '''
    if multi_level_rele:    #the common case with multi-level labels
        nums = torch.pow(2.0, sorted_labels[0:cutoff]) - 1.0
    else:
        nums = sorted_labels[0:cutoff]  #the case like listwise ranking, where the relevance is labeled as (n-rank_position)

    denoms = torch.log2(torch.arange(cutoff, dtype=torch.float) + 2.0)   #discounting factor
    dited_cumu_gain = torch.sum(nums/denoms)   # discounted cumulative gain value

    return dited_cumu_gain 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def torch_discounted_cumu_gain_at_k(sorted_labels, cutoff, multi_level_rele=True):
	'''
	ICML-nDCG, which places stronger emphasis on retrieving relevant documents
	:param sorted_labels: ranked labels (either standard or predicted by a system) in the form of np array
	:param max_cutoff: the maximum rank position to be considered
	:param multi_lavel_rele: either the case of multi-level relevance or the case of listwise int-value, e.g., MQ2007-list
	:return: cumulative gains for each rank position
	'''
	if multi_level_rele:    #the common case with multi-level labels
		nums = torch.pow(2.0, sorted_labels[0:cutoff]) - 1.0
	else:
		nums = sorted_labels[0:cutoff]  #the case like listwise ltr_adhoc, where the relevance is labeled as (n-rank_position)

	denoms = torch.log2(torch.arange(cutoff).type(torch.FloatTensor) + 2.0)   #discounting factor
	dited_cumu_gain = torch.sum(nums/denoms)   # discounted cumulative gain value

	return dited_cumu_gain 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def torch_discounted_cumu_gain_at_ks(sorted_labels, max_cutoff, multi_level_rele=True):
	'''
	ICML-nDCG, which places stronger emphasis on retrieving relevant documents
	:param sorted_labels: ranked labels (either standard or predicted by a system) in the form of np array
	:param max_cutoff: the maximum rank position to be considered
	:param multi_lavel_rele: either the case of multi-level relevance or the case of listwise int-value, e.g., MQ2007-list
	:return: cumulative gains for each rank position
	'''

	if multi_level_rele:    #the common case with multi-level labels
		nums = torch.pow(2.0, sorted_labels[0:max_cutoff]) - 1.0
	else:
		nums = sorted_labels[0:max_cutoff]  #the case like listwise ltr_adhoc, where the relevance is labeled as (n-rank_position)

	denoms = torch.log2(torch.arange(max_cutoff).type(torch.FloatTensor) + 2.0)   #discounting factor
	dited_cumu_gains = torch.cumsum(nums/denoms, dim=0)   # discounted cumulative gain value w.r.t. each position

	return dited_cumu_gains 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def get_delta_ndcg(batch_stds, batch_stds_sorted_via_preds):
    '''
    Delta-nDCG w.r.t. pairwise swapping of the currently predicted ltr_adhoc
    :param batch_stds: the standard labels sorted in a descending order
    :param batch_stds_sorted_via_preds: the standard labels sorted based on the corresponding predictions
    :return:
    '''
    batch_idcgs = torch_ideal_dcg(batch_sorted_labels=batch_stds, gpu=gpu)                      # ideal discount cumulative gains

    batch_gains = torch.pow(2.0, batch_stds_sorted_via_preds) - 1.0
    batch_n_gains = batch_gains / batch_idcgs               # normalised gains
    batch_ng_diffs = torch.unsqueeze(batch_n_gains, dim=2) - torch.unsqueeze(batch_n_gains, dim=1)

    batch_std_ranks = torch.arange(batch_stds_sorted_via_preds.size(1)).type(tensor)
    batch_dists = 1.0 / torch.log2(batch_std_ranks + 2.0)   # discount co-efficients
    batch_dists = torch.unsqueeze(batch_dists, dim=0)
    batch_dists_diffs = torch.unsqueeze(batch_dists, dim=2) - torch.unsqueeze(batch_dists, dim=1)
    batch_delta_ndcg = torch.abs(batch_ng_diffs) * torch.abs(batch_dists_diffs)  # absolute changes w.r.t. pairwise swapping

    return batch_delta_ndcg 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def __init__(self, output_size, scales, sampling_ratio, canonical_level=4):
        """
        Arguments:
            output_size (list[tuple[int]] or list[int]): output size for the pooled region
            scales (list[float]): scales for each Pooler
            sampling_ratio (int): sampling ratio for ROIAlign
        """
        super(Pooler, self).__init__()
        poolers = []
        for scale in scales:
            poolers.append(
                ROIAlign(
                    output_size, spatial_scale=scale, sampling_ratio=sampling_ratio
                )
            )
        self.poolers = nn.ModuleList(poolers)
        self.output_size = output_size
        # get the levels in the feature map by leveraging the fact that the network always
        # downsamples by a factor of 2 at each level.
        lvl_min = -torch.log2(torch.tensor(scales[0], dtype=torch.float32)).item()
        lvl_max = -torch.log2(torch.tensor(scales[-1], dtype=torch.float32)).item()
        self.map_levels = LevelMapper(
            lvl_min, lvl_max, canonical_level=canonical_level
        ) 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def _get_discount(self, slate_size: int) -> Tensor:
        weights = DCGSlateMetric._weights
        if (
            weights is None
            or weights.shape[0] < slate_size
            or weights.device != self._device
        ):
            DCGSlateMetric._weights = torch.reciprocal(
                torch.log2(
                    torch.arange(
                        2, slate_size + 2, dtype=torch.double, device=self._device
                    )
                )
            )
        weights = DCGSlateMetric._weights
        assert weights is not None
        return weights[:slate_size] 

# 需要導入模塊: import torch [as 別名]
# 或者: from torch import log2 [as 別名]
def compute(self, pred: torch.Tensor, target: torch.Tensor) -> torch.Tensor:
        """Compute the bits per character given the input and target.

        Parameters
        ----------
        pred: torch.Tensor
            input logits of shape (B x N)
        target: torch.LontTensor
            target tensor of shape (B)

        Returns
        -------
        torch.float
            Output perplexity

        """
        entropy = self.entropy(pred, target).mean()
        return torch.log2(torch.exp(entropy))