:nosearch:

.. _op_ai_onnx_Size-13:

Size - version 13
=================

This page documents version **13** of operator **Size**. See :doc:`Size` for the latest version (since version 25).

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

Takes a tensor as input and outputs a int64 scalar that equals to the total number of elements of the input tensor.

**Inputs**

- **data** (*T*): An input tensor.

**Outputs**

- **size** (*T1*): Total number of elements of the input tensor

**Type Constraints**

- **T**: Input tensor can be of arbitrary type.
  Allowed types: tensor(bfloat16), tensor(bool), tensor(complex128), tensor(complex64), tensor(double), tensor(float), tensor(float16), tensor(int16), tensor(int32), tensor(int64), tensor(int8), tensor(string), tensor(uint16), tensor(uint32), tensor(uint64), tensor(uint8).
- **T1**: Constrain output to int64 tensor, which should be a scalar though.
  Allowed types: tensor(int64).

Examples
--------

**test_cc_size**

.. code-block:: text

    Node:
      Size(x) -> (y)

.. code-block:: text

    Inputs:
      x: shape=(3, 4, 5), dtype=float32
        [[[0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.]],
        
         [[0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.]],
        
         [[0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.],
          [0., 0., 0., 0., 0.]]]

    Outputs:
      y: shape=(), dtype=int64
        60

**test_cc_size_empty**

.. code-block:: text

    Node:
      Size(x) -> (y)

.. code-block:: text

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

    Outputs:
      y: shape=(), dtype=int64
        0

**test_cc_size_example**

.. code-block:: text

    Node:
      Size(x) -> (y)

.. code-block:: text

    Inputs:
      x: shape=(2, 3), dtype=float32
        [[1., 2., 3.],
         [4., 5., 6.]]

    Outputs:
      y: shape=(), dtype=int64
        6

**test_cc_size_scalar**

.. code-block:: text

    Node:
      Size(x) -> (y)

.. code-block:: text

    Inputs:
      x: shape=(), dtype=float32
        42.

    Outputs:
      y: shape=(), dtype=int64
        1

Differences with previous version (1)
-------------------------------------

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

* old version: 1
* new version: 13
* breaking: no

**Type constraints:**

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