digamma¶

paddle. digamma ( x, name=None ) [source]

Calculates the digamma of the given input tensor, element-wise.

$$Out = \Psi(x) = \frac{ \Gamma^{'}(x) }{ \Gamma(x) }$$

Parameters

• x (Tensor) – Input Tensor. Must be one of the following types: float32, float64.

• name (str, optional) – The default value is None. Normally there is no need for user to set this property. For more information, please refer to Name

Returns

Tensor, the digamma of the input Tensor, the shape and data type is the same with input.

Examples

import paddle

data = paddle.to_tensor([[1, 1.5], [0, -2.2]], dtype='float32')
res = paddle.digamma(data)
print(res)
# Tensor(shape=[2, 2], dtype=float32, place=CUDAPlace(0), stop_gradient=True,
#       [[-0.57721591,  0.03648996],
#        [ nan       ,  5.32286835]])