Split

Versioned name: Split-1

Category: Data movement

Short description: Split operation splits an input tensor into pieces of the same length along some axis.

Detailed Description

Split operation splits a given input tensor data into chunks of the same length along a scalar axis. It produces multiple output tensors based on num_splits attribute. The i-th output tensor shape is equal to the input tensor data shape, except for dimension along axis which is data.shape[axis]/num_splits.

\[shape\_output\_tensor = [data.shape[0], data.shape[1], \dotsc , data.shape[axis]/num\_splits, \dotsc data.shape[D-1]]\]

Where D is the rank of input tensor data. The axis being split must be evenly divided by num_splits attribute.

Attributes

  • num_splits

    • Description: number of outputs into which the input tensor data will be split along axis dimension. The dimension of data shape along axis must be evenly divisible by num_splits

    • Range of values: an integer within the range [1, data.shape[axis]]

    • Type: int

    • Required: yes

Inputs

  • 1: data. A tensor of type T and arbitrary shape. Required.

  • 2: axis. Axis along data to split. A scalar of type T_AXIS within the range [-rank(data), rank(data) - 1]. Negative values address dimensions from the end. Required.

  • Note: The dimension of input tensor data shape along axis must be evenly divisible by num_splits attribute.

Outputs

  • Multiple outputs: Tensors of type T. The i-th output has the same shape as data input tensor except for dimension along axis which is data.shape[axis]/num_splits.

Types

  • T: any arbitrary supported type.

  • T_AXIS: any integer type.

Example

 <layer id="1" type="Split" ...>
     <data num_splits="3" />
     <input>
         <port id="0">       <!-- some data -->
             <dim>6</dim>
             <dim>12</dim>
             <dim>10</dim>
             <dim>24</dim>
         </port>
         <port id="1">       <!-- axis: 1 -->
         </port>
     </input>
     <output>
         <port id="2">
             <dim>6</dim>
             <dim>4</dim>
             <dim>10</dim>
             <dim>24</dim>
         </port>
         <port id="3">
             <dim>6</dim>
             <dim>4</dim>
             <dim>10</dim>
             <dim>24</dim>
         </port>
         <port id="4">
             <dim>6</dim>
             <dim>4</dim>
             <dim>10</dim>
             <dim>24</dim>
         </port>
     </output>
 </layer>