.. _op_ai_onnx_Mean:

Mean
====

- **Domain**: ``ai.onnx``
- **Since version**: 13

Element-wise mean of each of the input tensors (with Numpy-style broadcasting support).
All inputs and outputs must have the same data type.

This operator supports **multidirectional (i.e., Numpy-style) broadcasting**; for more details please check `the doc <Broadcasting.md>`_.

**Inputs**

- **data_0** (*T*): List of tensors for mean.

**Outputs**

- **mean** (*T*): Output tensor.

**Type Constraints**

- **T**: Constrain input and output types to float tensors.
  Allowed types: tensor(bfloat16), tensor(double), tensor(float), tensor(float16).

Examples
--------

**test_cc_mean_bcast**

.. code-block:: text

    Node:
      Mean(data_0, data_1) -> (result)

.. code-block:: text

    Inputs:
      data_0: shape=(2, 2), dtype=float32
        [[1., 2.],
         [3., 4.]]
      data_1: shape=(), dtype=float32
        10.

    Outputs:
      result: shape=(2, 2), dtype=float32
        [[5.5, 6. ],
         [6.5, 7. ]]

**test_mean_example**

.. code-block:: text

    Node:
      Mean(data_0, data_1, data_2) -> (result)

.. code-block:: text

    Inputs:
      data_0: shape=(3,), dtype=float32
        [3., 0., 2.]
      data_1: shape=(3,), dtype=float32
        [1., 3., 4.]
      data_2: shape=(3,), dtype=float32
        [2., 6., 6.]

    Outputs:
      result: shape=(3,), dtype=float32
        [2., 3., 4.]

**test_mean_one_input**

.. code-block:: text

    Node:
      Mean(data_0) -> (result)

.. code-block:: text

    Inputs:
      data_0: shape=(3,), dtype=float32
        [3., 0., 2.]

    Outputs:
      result: shape=(3,), dtype=float32
        [3., 0., 2.]

**test_mean_two_inputs**

.. code-block:: text

    Node:
      Mean(data_0, data_1) -> (result)

.. code-block:: text

    Inputs:
      data_0: shape=(3,), dtype=float32
        [3., 0., 2.]
      data_1: shape=(3,), dtype=float32
        [1., 3., 4.]

    Outputs:
      result: shape=(3,), dtype=float32
        [2. , 1.5, 3. ]

Differences with previous version (8)
-------------------------------------

**SchemaDiff**: ``Mean`` (domain ``'ai.onnx'``)

* old version: 8
* new version: 13
* breaking: no

**Type constraints:**

* changed 'T': added types: ['tensor(bfloat16)']

Version History
---------------

- :doc:`Version 8 <Mean-8>`
- :doc:`Version 6 <Mean-6>`
- :doc:`Version 1 <Mean-1>`