| import torch |
| from torch._C import _add_docstr, _special # type: ignore[attr-defined] |
| from torch._torch_docs import common_args, multi_dim_common |
| |
| __all__ = ['entr', 'psi', 'digamma', 'gammaln', 'polygamma', 'erf', 'erfc', 'erfinv', |
| 'erfcx', 'logit', 'logsumexp', 'expit', 'exp2', 'expm1', 'xlog1py', 'xlogy', |
| 'i0', 'i0e', 'i1', 'i1e', 'ndtr', 'ndtri', 'log_ndtr', 'log1p', 'sinc', 'round', 'log_softmax', |
| 'zeta', 'multigammaln', 'gammainc', 'gammaincc', 'softmax'] |
| |
| Tensor = torch.Tensor |
| |
| entr = _add_docstr(_special.special_entr, |
| r""" |
| entr(input, *, out=None) -> Tensor |
| Computes the entropy on :attr:`input` (as defined below), elementwise. |
| |
| .. math:: |
| \begin{align} |
| \text{entr(x)} = \begin{cases} |
| -x * \ln(x) & x > 0 \\ |
| 0 & x = 0.0 \\ |
| -\infty & x < 0 |
| \end{cases} |
| \end{align} |
| """ + """ |
| |
| Args: |
| input (Tensor): the input tensor. |
| |
| Keyword args: |
| out (Tensor, optional): the output tensor. |
| |
| Example:: |
| >>> a = torch.arange(-0.5, 1, 0.5) |
| >>> a |
| tensor([-0.5000, 0.0000, 0.5000]) |
| >>> torch.special.entr(a) |
| tensor([ -inf, 0.0000, 0.3466]) |
| """) |
| |
| psi = _add_docstr(_special.special_psi, |
| r""" |
| psi(input, *, out=None) -> Tensor |
| |
| Alias for :func:`torch.special.digamma`. |
| """) |
| |
| digamma = _add_docstr(_special.special_digamma, |
| r""" |
| digamma(input, *, out=None) -> Tensor |
| |
| Computes the logarithmic derivative of the gamma function on `input`. |
| |
| .. math:: |
| \digamma(x) = \frac{d}{dx} \ln\left(\Gamma\left(x\right)\right) = \frac{\Gamma'(x)}{\Gamma(x)} |
| """ + r""" |
| Args: |
| input (Tensor): the tensor to compute the digamma function on |
| |
| Keyword args: |
| {out} |
| |
| .. note:: This function is similar to SciPy's `scipy.special.digamma`. |
| |
| .. note:: From PyTorch 1.8 onwards, the digamma function returns `-Inf` for `0`. |
| Previously it returned `NaN` for `0`. |
| |
| Example:: |
| |
| >>> a = torch.tensor([1, 0.5]) |
| >>> torch.special.digamma(a) |
| tensor([-0.5772, -1.9635]) |
| |
| """.format(**common_args)) |
| |
| gammaln = _add_docstr(_special.special_gammaln, |
| r""" |
| gammaln(input, *, out=None) -> Tensor |
| |
| Computes the natural logarithm of the absolute value of the gamma function on :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = \ln \Gamma(|\text{input}_{i}|) |
| """ + """ |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> a = torch.arange(0.5, 2, 0.5) |
| >>> torch.special.gammaln(a) |
| tensor([ 0.5724, 0.0000, -0.1208]) |
| |
| """.format(**common_args)) |
| |
| polygamma = _add_docstr(_special.special_polygamma, |
| r""" |
| polygamma(n, input, *, out=None) -> Tensor |
| |
| Computes the :math:`n^{th}` derivative of the digamma function on :attr:`input`. |
| :math:`n \geq 0` is called the order of the polygamma function. |
| |
| .. math:: |
| \psi^{(n)}(x) = \frac{d^{(n)}}{dx^{(n)}} \psi(x) |
| |
| .. note:: |
| This function is implemented only for nonnegative integers :math:`n \geq 0`. |
| """ + """ |
| Args: |
| n (int): the order of the polygamma function |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> a = torch.tensor([1, 0.5]) |
| >>> torch.special.polygamma(1, a) |
| tensor([1.64493, 4.9348]) |
| >>> torch.special.polygamma(2, a) |
| tensor([ -2.4041, -16.8288]) |
| >>> torch.special.polygamma(3, a) |
| tensor([ 6.4939, 97.4091]) |
| >>> torch.special.polygamma(4, a) |
| tensor([ -24.8863, -771.4742]) |
| """.format(**common_args)) |
| |
| erf = _add_docstr(_special.special_erf, |
| r""" |
| erf(input, *, out=None) -> Tensor |
| |
| Computes the error function of :attr:`input`. The error function is defined as follows: |
| |
| .. math:: |
| \mathrm{erf}(x) = \frac{2}{\sqrt{\pi}} \int_{0}^{x} e^{-t^2} dt |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.erf(torch.tensor([0, -1., 10.])) |
| tensor([ 0.0000, -0.8427, 1.0000]) |
| """.format(**common_args)) |
| |
| erfc = _add_docstr(_special.special_erfc, |
| r""" |
| erfc(input, *, out=None) -> Tensor |
| |
| Computes the complementary error function of :attr:`input`. |
| The complementary error function is defined as follows: |
| |
| .. math:: |
| \mathrm{erfc}(x) = 1 - \frac{2}{\sqrt{\pi}} \int_{0}^{x} e^{-t^2} dt |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.erfc(torch.tensor([0, -1., 10.])) |
| tensor([ 1.0000, 1.8427, 0.0000]) |
| """.format(**common_args)) |
| |
| erfcx = _add_docstr(_special.special_erfcx, |
| r""" |
| erfcx(input, *, out=None) -> Tensor |
| |
| Computes the scaled complementary error function for each element of :attr:`input`. |
| The scaled complementary error function is defined as follows: |
| |
| .. math:: |
| \mathrm{erfcx}(x) = e^{x^2} \mathrm{erfc}(x) |
| """ + r""" |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.erfcx(torch.tensor([0, -1., 10.])) |
| tensor([ 1.0000, 5.0090, 0.0561]) |
| """.format(**common_args)) |
| |
| erfinv = _add_docstr(_special.special_erfinv, |
| r""" |
| erfinv(input, *, out=None) -> Tensor |
| |
| Computes the inverse error function of :attr:`input`. |
| The inverse error function is defined in the range :math:`(-1, 1)` as: |
| |
| .. math:: |
| \mathrm{erfinv}(\mathrm{erf}(x)) = x |
| """ + r""" |
| |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.erfinv(torch.tensor([0, 0.5, -1.])) |
| tensor([ 0.0000, 0.4769, -inf]) |
| """.format(**common_args)) |
| |
| logit = _add_docstr(_special.special_logit, |
| r""" |
| logit(input, eps=None, *, out=None) -> Tensor |
| |
| Returns a new tensor with the logit of the elements of :attr:`input`. |
| :attr:`input` is clamped to [eps, 1 - eps] when eps is not None. |
| When eps is None and :attr:`input` < 0 or :attr:`input` > 1, the function will yields NaN. |
| |
| .. math:: |
| \begin{align} |
| y_{i} &= \ln(\frac{z_{i}}{1 - z_{i}}) \\ |
| z_{i} &= \begin{cases} |
| x_{i} & \text{if eps is None} \\ |
| \text{eps} & \text{if } x_{i} < \text{eps} \\ |
| x_{i} & \text{if } \text{eps} \leq x_{i} \leq 1 - \text{eps} \\ |
| 1 - \text{eps} & \text{if } x_{i} > 1 - \text{eps} |
| \end{cases} |
| \end{align} |
| """ + r""" |
| Args: |
| {input} |
| eps (float, optional): the epsilon for input clamp bound. Default: ``None`` |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> a = torch.rand(5) |
| >>> a |
| tensor([0.2796, 0.9331, 0.6486, 0.1523, 0.6516]) |
| >>> torch.special.logit(a, eps=1e-6) |
| tensor([-0.9466, 2.6352, 0.6131, -1.7169, 0.6261]) |
| """.format(**common_args)) |
| |
| logsumexp = _add_docstr(_special.special_logsumexp, |
| r""" |
| logsumexp(input, dim, keepdim=False, *, out=None) |
| |
| Alias for :func:`torch.logsumexp`. |
| """.format(**multi_dim_common)) |
| |
| expit = _add_docstr(_special.special_expit, |
| r""" |
| expit(input, *, out=None) -> Tensor |
| |
| Computes the expit (also known as the logistic sigmoid function) of the elements of :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = \frac{1}{1 + e^{-\text{input}_{i}}} |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> t = torch.randn(4) |
| >>> t |
| tensor([ 0.9213, 1.0887, -0.8858, -1.7683]) |
| >>> torch.special.expit(t) |
| tensor([ 0.7153, 0.7481, 0.2920, 0.1458]) |
| """.format(**common_args)) |
| |
| exp2 = _add_docstr(_special.special_exp2, |
| r""" |
| exp2(input, *, out=None) -> Tensor |
| |
| Computes the base two exponential function of :attr:`input`. |
| |
| .. math:: |
| y_{i} = 2^{x_{i}} |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.exp2(torch.tensor([0, math.log2(2.), 3, 4])) |
| tensor([ 1., 2., 8., 16.]) |
| """.format(**common_args)) |
| |
| expm1 = _add_docstr(_special.special_expm1, |
| r""" |
| expm1(input, *, out=None) -> Tensor |
| |
| Computes the exponential of the elements minus 1 |
| of :attr:`input`. |
| |
| .. math:: |
| y_{i} = e^{x_{i}} - 1 |
| |
| .. note:: This function provides greater precision than exp(x) - 1 for small values of x. |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.special.expm1(torch.tensor([0, math.log(2.)])) |
| tensor([ 0., 1.]) |
| """.format(**common_args)) |
| |
| xlog1py = _add_docstr(_special.special_xlog1py, |
| r""" |
| xlog1py(input, other, *, out=None) -> Tensor |
| |
| Computes ``input * log1p(other)`` with the following cases. |
| |
| .. math:: |
| \text{out}_{i} = \begin{cases} |
| \text{NaN} & \text{if } \text{other}_{i} = \text{NaN} \\ |
| 0 & \text{if } \text{input}_{i} = 0.0 \text{ and } \text{other}_{i} != \text{NaN} \\ |
| \text{input}_{i} * \text{log1p}(\text{other}_{i})& \text{otherwise} |
| \end{cases} |
| |
| Similar to SciPy's `scipy.special.xlog1py`. |
| |
| """ + r""" |
| |
| Args: |
| input (Number or Tensor) : Multiplier |
| other (Number or Tensor) : Argument |
| |
| .. note:: At least one of :attr:`input` or :attr:`other` must be a tensor. |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> x = torch.zeros(5,) |
| >>> y = torch.tensor([-1, 0, 1, float('inf'), float('nan')]) |
| >>> torch.special.xlog1py(x, y) |
| tensor([0., 0., 0., 0., nan]) |
| >>> x = torch.tensor([1, 2, 3]) |
| >>> y = torch.tensor([3, 2, 1]) |
| >>> torch.special.xlog1py(x, y) |
| tensor([1.3863, 2.1972, 2.0794]) |
| >>> torch.special.xlog1py(x, 4) |
| tensor([1.6094, 3.2189, 4.8283]) |
| >>> torch.special.xlog1py(2, y) |
| tensor([2.7726, 2.1972, 1.3863]) |
| """.format(**common_args)) |
| |
| xlogy = _add_docstr(_special.special_xlogy, |
| r""" |
| xlogy(input, other, *, out=None) -> Tensor |
| |
| Computes ``input * log(other)`` with the following cases. |
| |
| .. math:: |
| \text{out}_{i} = \begin{cases} |
| \text{NaN} & \text{if } \text{other}_{i} = \text{NaN} \\ |
| 0 & \text{if } \text{input}_{i} = 0.0 \\ |
| \text{input}_{i} * \log{(\text{other}_{i})} & \text{otherwise} |
| \end{cases} |
| |
| Similar to SciPy's `scipy.special.xlogy`. |
| |
| """ + r""" |
| |
| Args: |
| input (Number or Tensor) : Multiplier |
| other (Number or Tensor) : Argument |
| |
| .. note:: At least one of :attr:`input` or :attr:`other` must be a tensor. |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> x = torch.zeros(5,) |
| >>> y = torch.tensor([-1, 0, 1, float('inf'), float('nan')]) |
| >>> torch.special.xlogy(x, y) |
| tensor([0., 0., 0., 0., nan]) |
| >>> x = torch.tensor([1, 2, 3]) |
| >>> y = torch.tensor([3, 2, 1]) |
| >>> torch.special.xlogy(x, y) |
| tensor([1.0986, 1.3863, 0.0000]) |
| >>> torch.special.xlogy(x, 4) |
| tensor([1.3863, 2.7726, 4.1589]) |
| >>> torch.special.xlogy(2, y) |
| tensor([2.1972, 1.3863, 0.0000]) |
| """.format(**common_args)) |
| |
| i0 = _add_docstr(_special.special_i0, |
| r""" |
| i0(input, *, out=None) -> Tensor |
| |
| Computes the zeroth order modified Bessel function of the first kind for each element of :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = I_0(\text{input}_{i}) = \sum_{k=0}^{\infty} \frac{(\text{input}_{i}^2/4)^k}{(k!)^2} |
| |
| """ + r""" |
| Args: |
| input (Tensor): the input tensor |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> torch.i0(torch.arange(5, dtype=torch.float32)) |
| tensor([ 1.0000, 1.2661, 2.2796, 4.8808, 11.3019]) |
| |
| """.format(**common_args)) |
| |
| i0e = _add_docstr(_special.special_i0e, |
| r""" |
| i0e(input, *, out=None) -> Tensor |
| Computes the exponentially scaled zeroth order modified Bessel function of the first kind (as defined below) |
| for each element of :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = \exp(-|x|) * i0(x) = \exp(-|x|) * \sum_{k=0}^{\infty} \frac{(\text{input}_{i}^2/4)^k}{(k!)^2} |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.i0e(torch.arange(5, dtype=torch.float32)) |
| tensor([1.0000, 0.4658, 0.3085, 0.2430, 0.2070]) |
| """.format(**common_args)) |
| |
| i1 = _add_docstr(_special.special_i1, |
| r""" |
| i1(input, *, out=None) -> Tensor |
| Computes the first order modified Bessel function of the first kind (as defined below) |
| for each element of :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = \frac{(\text{input}_{i})}{2} * \sum_{k=0}^{\infty} \frac{(\text{input}_{i}^2/4)^k}{(k!) * (k+1)!} |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.i1(torch.arange(5, dtype=torch.float32)) |
| tensor([0.0000, 0.5652, 1.5906, 3.9534, 9.7595]) |
| """.format(**common_args)) |
| |
| i1e = _add_docstr(_special.special_i1e, |
| r""" |
| i1e(input, *, out=None) -> Tensor |
| Computes the exponentially scaled first order modified Bessel function of the first kind (as defined below) |
| for each element of :attr:`input`. |
| |
| .. math:: |
| \text{out}_{i} = \exp(-|x|) * i1(x) = |
| \exp(-|x|) * \frac{(\text{input}_{i})}{2} * \sum_{k=0}^{\infty} \frac{(\text{input}_{i}^2/4)^k}{(k!) * (k+1)!} |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.i1e(torch.arange(5, dtype=torch.float32)) |
| tensor([0.0000, 0.2079, 0.2153, 0.1968, 0.1788]) |
| """.format(**common_args)) |
| |
| ndtr = _add_docstr(_special.special_ndtr, |
| r""" |
| ndtr(input, *, out=None) -> Tensor |
| Computes the area under the standard Gaussian probability density function, |
| integrated from minus infinity to :attr:`input`, elementwise. |
| |
| .. math:: |
| \text{ndtr}(x) = \frac{1}{\sqrt{2 \pi}}\int_{-\infty}^{x} e^{-\frac{1}{2}t^2} dt |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.ndtr(torch.tensor([-3., -2, -1, 0, 1, 2, 3])) |
| tensor([0.0013, 0.0228, 0.1587, 0.5000, 0.8413, 0.9772, 0.9987]) |
| """.format(**common_args)) |
| |
| ndtri = _add_docstr(_special.special_ndtri, |
| r""" |
| ndtri(input, *, out=None) -> Tensor |
| Computes the argument, x, for which the area under the Gaussian probability density function |
| (integrated from minus infinity to x) is equal to :attr:`input`, elementwise. |
| |
| .. math:: |
| \text{ndtri}(p) = \sqrt{2}\text{erf}^{-1}(2p - 1) |
| |
| .. note:: |
| Also known as quantile function for Normal Distribution. |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.ndtri(torch.tensor([0, 0.25, 0.5, 0.75, 1])) |
| tensor([ -inf, -0.6745, 0.0000, 0.6745, inf]) |
| """.format(**common_args)) |
| |
| log_ndtr = _add_docstr(_special.special_log_ndtr, |
| r""" |
| log_ndtr(input, *, out=None) -> Tensor |
| Computes the log of the area under the standard Gaussian probability density function, |
| integrated from minus infinity to :attr:`input`, elementwise. |
| |
| .. math:: |
| \text{log\_ndtr}(x) = \log\left(\frac{1}{\sqrt{2 \pi}}\int_{-\infty}^{x} e^{-\frac{1}{2}t^2} dt \right) |
| |
| """ + r""" |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> torch.special.log_ndtr(torch.tensor([-3., -2, -1, 0, 1, 2, 3])) |
| tensor([-6.6077 -3.7832 -1.841 -0.6931 -0.1728 -0.023 -0.0014]) |
| """.format(**common_args)) |
| |
| log1p = _add_docstr(_special.special_log1p, |
| r""" |
| log1p(input, *, out=None) -> Tensor |
| |
| Alias for :func:`torch.log1p`. |
| """) |
| |
| sinc = _add_docstr(_special.special_sinc, |
| r""" |
| sinc(input, *, out=None) -> Tensor |
| |
| Computes the normalized sinc of :attr:`input.` |
| |
| .. math:: |
| \text{out}_{i} = |
| \begin{cases} |
| 1, & \text{if}\ \text{input}_{i}=0 \\ |
| \sin(\pi \text{input}_{i}) / (\pi \text{input}_{i}), & \text{otherwise} |
| \end{cases} |
| """ + r""" |
| |
| Args: |
| {input} |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> t = torch.randn(4) |
| >>> t |
| tensor([ 0.2252, -0.2948, 1.0267, -1.1566]) |
| >>> torch.special.sinc(t) |
| tensor([ 0.9186, 0.8631, -0.0259, -0.1300]) |
| """.format(**common_args)) |
| |
| round = _add_docstr(_special.special_round, |
| r""" |
| round(input, *, out=None) -> Tensor |
| |
| Alias for :func:`torch.round`. |
| """) |
| |
| softmax = _add_docstr(_special.special_softmax, |
| r""" |
| softmax(input, dim, *, dtype=None) -> Tensor |
| |
| Computes the softmax function. |
| |
| Softmax is defined as: |
| |
| :math:`\text{Softmax}(x_{i}) = \frac{\exp(x_i)}{\sum_j \exp(x_j)}` |
| |
| It is applied to all slices along dim, and will re-scale them so that the elements |
| lie in the range `[0, 1]` and sum to 1. |
| |
| Args: |
| input (Tensor): input |
| dim (int): A dimension along which softmax will be computed. |
| dtype (:class:`torch.dtype`, optional): the desired data type of returned tensor. |
| If specified, the input tensor is cast to :attr:`dtype` before the operation |
| is performed. This is useful for preventing data type overflows. Default: None. |
| |
| Examples:: |
| >>> t = torch.ones(2, 2) |
| >>> torch.special.softmax(t, 0) |
| tensor([[0.5000, 0.5000], |
| [0.5000, 0.5000]]) |
| |
| """) |
| |
| log_softmax = _add_docstr(_special.special_log_softmax, |
| r""" |
| log_softmax(input, dim, *, dtype=None) -> Tensor |
| |
| Computes softmax followed by a logarithm. |
| |
| While mathematically equivalent to log(softmax(x)), doing these two |
| operations separately is slower and numerically unstable. This function |
| is computed as: |
| |
| .. math:: |
| \text{log\_softmax}(x_{i}) = \log\left(\frac{\exp(x_i) }{ \sum_j \exp(x_j)} \right) |
| """ + r""" |
| |
| Args: |
| input (Tensor): input |
| dim (int): A dimension along which log_softmax will be computed. |
| dtype (:class:`torch.dtype`, optional): the desired data type of returned tensor. |
| If specified, the input tensor is cast to :attr:`dtype` before the operation |
| is performed. This is useful for preventing data type overflows. Default: None. |
| |
| Example:: |
| >>> t = torch.ones(2, 2) |
| >>> torch.special.log_softmax(t, 0) |
| tensor([[-0.6931, -0.6931], |
| [-0.6931, -0.6931]]) |
| """) |
| |
| zeta = _add_docstr(_special.special_zeta, |
| r""" |
| zeta(input, other, *, out=None) -> Tensor |
| |
| Computes the Hurwitz zeta function, elementwise. |
| |
| .. math:: |
| \zeta(x, q) = \sum_{k=0}^{\infty} \frac{1}{(k + q)^x} |
| |
| """ + r""" |
| Args: |
| input (Tensor): the input tensor corresponding to `x`. |
| other (Tensor): the input tensor corresponding to `q`. |
| |
| .. note:: |
| The Riemann zeta function corresponds to the case when `q = 1` |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| >>> x = torch.tensor([2., 4.]) |
| >>> torch.special.zeta(x, 1) |
| tensor([1.6449, 1.0823]) |
| >>> torch.special.zeta(x, torch.tensor([1., 2.])) |
| tensor([1.6449, 0.0823]) |
| >>> torch.special.zeta(2, torch.tensor([1., 2.])) |
| tensor([1.6449, 0.6449]) |
| """.format(**common_args)) |
| |
| multigammaln = _add_docstr(_special.special_multigammaln, |
| r""" |
| multigammaln(input, p, *, out=None) -> Tensor |
| |
| Computes the `multivariate log-gamma function |
| <https://en.wikipedia.org/wiki/Multivariate_gamma_function>`_ with dimension |
| :math:`p` element-wise, given by |
| |
| .. math:: |
| \log(\Gamma_{p}(a)) = C + \displaystyle \sum_{i=1}^{p} \log\left(\Gamma\left(a - \frac{i - 1}{2}\right)\right) |
| |
| where :math:`C = \log(\pi) \times \frac{p (p - 1)}{4}` and :math:`\Gamma(\cdot)` is the Gamma function. |
| |
| All elements must be greater than :math:`\frac{p - 1}{2}`, otherwise an error would be thrown. |
| """ + """ |
| |
| Args: |
| input (Tensor): the tensor to compute the multivariate log-gamma function |
| p (int): the number of dimensions |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> a = torch.empty(2, 3).uniform_(1, 2) |
| >>> a |
| tensor([[1.6835, 1.8474, 1.1929], |
| [1.0475, 1.7162, 1.4180]]) |
| >>> torch.special.multigammaln(a, 2) |
| tensor([[0.3928, 0.4007, 0.7586], |
| [1.0311, 0.3901, 0.5049]]) |
| """.format(**common_args)) |
| |
| gammainc = _add_docstr(_special.special_gammainc, |
| r""" |
| gammainc(input, other, *, out=None) -> Tensor |
| |
| Computes the regularized lower incomplete gamma function: |
| |
| .. math:: |
| \text{out}_{i} = \frac{1}{\Gamma(\text{input}_i)} \int_0^{\text{other}_i} t^{\text{input}_i-1} e^{-t} dt |
| |
| where both :math:`\text{input}_i` and :math:`\text{other}_i` are weakly positive |
| and at least one is strictly positive. |
| If both are zero or either is negative then :math:`\text{out}_i=\text{nan}`. |
| :math:`\Gamma(\cdot)` in the equation above is the gamma function, |
| |
| .. math:: |
| \Gamma(\text{input}_i) = \int_0^\infty t^{(\text{input}_i-1)} e^{-t} dt. |
| |
| See :func:`torch.special.gammaincc` and :func:`torch.special.gammaln` for related functions. |
| |
| Supports :ref:`broadcasting to a common shape <broadcasting-semantics>` |
| and float inputs. |
| |
| .. note:: |
| The backward pass with respect to :attr:`input` is not yet supported. |
| Please open an issue on PyTorch's Github to request it. |
| |
| """ + r""" |
| Args: |
| input (Tensor): the first non-negative input tensor |
| other (Tensor): the second non-negative input tensor |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> a1 = torch.tensor([4.0]) |
| >>> a2 = torch.tensor([3.0, 4.0, 5.0]) |
| >>> a = torch.special.gammaincc(a1, a2) |
| tensor([0.3528, 0.5665, 0.7350]) |
| tensor([0.3528, 0.5665, 0.7350]) |
| >>> b = torch.special.gammainc(a1, a2) + torch.special.gammaincc(a1, a2) |
| tensor([1., 1., 1.]) |
| |
| """.format(**common_args)) |
| |
| gammaincc = _add_docstr(_special.special_gammaincc, |
| r""" |
| gammaincc(input, other, *, out=None) -> Tensor |
| |
| Computes the regularized upper incomplete gamma function: |
| |
| .. math:: |
| \text{out}_{i} = \frac{1}{\Gamma(\text{input}_i)} \int_{\text{other}_i}^{\infty} t^{\text{input}_i-1} e^{-t} dt |
| |
| where both :math:`\text{input}_i` and :math:`\text{other}_i` are weakly positive |
| and at least one is strictly positive. |
| If both are zero or either is negative then :math:`\text{out}_i=\text{nan}`. |
| :math:`\Gamma(\cdot)` in the equation above is the gamma function, |
| |
| .. math:: |
| \Gamma(\text{input}_i) = \int_0^\infty t^{(\text{input}_i-1)} e^{-t} dt. |
| |
| See :func:`torch.special.gammainc` and :func:`torch.special.gammaln` for related functions. |
| |
| Supports :ref:`broadcasting to a common shape <broadcasting-semantics>` |
| and float inputs. |
| |
| .. note:: |
| The backward pass with respect to :attr:`input` is not yet supported. |
| Please open an issue on PyTorch's Github to request it. |
| |
| """ + r""" |
| Args: |
| input (Tensor): the first non-negative input tensor |
| other (Tensor): the second non-negative input tensor |
| |
| Keyword args: |
| {out} |
| |
| Example:: |
| |
| >>> a1 = torch.tensor([4.0]) |
| >>> a2 = torch.tensor([3.0, 4.0, 5.0]) |
| >>> a = torch.special.gammaincc(a1, a2) |
| tensor([0.6472, 0.4335, 0.2650]) |
| >>> b = torch.special.gammainc(a1, a2) + torch.special.gammaincc(a1, a2) |
| tensor([1., 1., 1.]) |
| |
| """.format(**common_args)) |