# W3cubDocs

/TensorFlow Python

# tf.igammac

### tf.igammac

igammac(
a,
x,
name=None
)


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

See the guide: Math > Basic Math Functions

Compute the upper regularized incomplete Gamma function Q(a, x).

The upper regularized incomplete Gamma function is defined as:

$$Q(a, x) = Gamma(a, x) / Gamma(a) = 1 - P(a, x)$$

where

$$Gamma(a, x) = int_{x}^{\infty} t^{a-1} exp(-t) dt$$

is the upper incomplete Gama function.

Note, above P(a, x) (Igamma) is the lower regularized complete Gamma 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.