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/TensorFlow Python

# tf.polygamma

tf.polygamma(
a,
x,
name=None
)


Defined in tensorflow/python/ops/gen_math_ops.py.

See the guide: Math > Basic Math Functions

Compute the polygamma function $$\psi^{(n)} (x)$$.

The polygamma function is defined as:

$$\psi^{(n)} (x) = \frac{d^n}{dx^n} \psi(x)$$

where $$\psi(x)$$ is the digamma function.

#### Args:

• a: A Tensor. Must be one of the following types: float32, float64.
• x: A Tensor. Must have the same type as a.
• name: A name for the operation (optional).

#### Returns:

A Tensor. Has the same type as a.