:nosearch:

.. _op_ai_onnx_Split-2:

Split - version 2
=================

This page documents version **2** of operator **Split**. See :doc:`Split` for the latest version (since version 18).

- **Domain**: ``ai.onnx``
- **Since version**: 2

Split a tensor into a list of tensors, along the specified
'axis'. Lengths of the parts can be specified using argument 'split'.
Otherwise, the tensor is split to equal sized parts.

**Inputs**

- **input** (*T*): The tensor to split

**Outputs**

Between 1 and ∞ outputs.

- **outputs** (*T*): One or more outputs forming list of tensors after splitting

**Attributes**

- **axis** (*int*): Which axis to split on.
- **split** (*int[]*): length of each output. Values should be >= 0.

**Type Constraints**

- **T**: Constrain input and output types to all tensor types.
  Allowed types: 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).

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

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

* old version: 1
* new version: 2
* breaking: **yes**

**Breaking reasons:**

* input 'split' (removed): was at position 1
* output 'outputs...' (removed): was at position 0
* output 'outputs' (added): at position 0; option=Single; type_str='T'
* attribute 'axis' (changed): default value changed UNDEFINED -> 0

**Inputs:**

* [BREAKING] removed 'split': was at position 1

**Outputs:**

* [BREAKING] removed 'outputs...': was at position 0
* [BREAKING] added 'outputs': at position 0; option=Single; type_str='T'

**Attributes:**

* [BREAKING] changed 'axis': default value changed UNDEFINED -> 0

**Type constraints:**

* changed 'T': added types: ['tensor(bool)', 'tensor(complex128)', 'tensor(complex64)', 'tensor(int16)', 'tensor(int32)', 'tensor(int64)', 'tensor(int8)', 'tensor(string)', 'tensor(uint16)', 'tensor(uint32)', 'tensor(uint64)', 'tensor(uint8)']

**Documentation:**

* line similarity: 0.29 (+2/-3 lines)

.. code-block:: diff

    --- Split v1
    +++ Split v2
    @@ -1,4 +1,3 @@
     Split a tensor into a list of tensors, along the specified
    -'axis'. The lengths of the split can be specified using argument 'axis' or
    -optional second input blob to the operator. Otherwise, the tensor is split
    -to equal sized parts.
    +'axis'. Lengths of the parts can be specified using argument 'split'.
    +Otherwise, the tensor is split to equal sized parts.