Unsqueeze¶

Versioned name : Unsqueeze-1

Category : Shape manipulation

Short description : Unsqueeze adds dimensions of size 1 to the first input tensor. The second input value specifies a list of dimensions that will be inserted. Indices specify dimensions in the output tensor.

Attributes : Unsqueeze operation doesn’t have attributes.

Inputs :

1 : Tensor of type T and arbitrary shape. Required.
2 : Scalar or 1D tensor of type T_INT with indices of dimensions to unsqueeze. Values could be negative (have to be from range [-R, R-1], where R is the rank of the output). Required.

Outputs :

1 : Tensor with unsqueezed values of type T.

Types

T : any numeric type.
T_INT : any supported integer type.

Example

Example 1: unsqueeze 2D tensor to a 4D tensor

<layer ... type="Unsqueeze">
    <input>
        <port id="0">
            <dim>2</dim>
            <dim>3</dim>
        </port>
    </input>
    <input>
        <port id="1">
            <dim>2</dim>  <!-- value is [0, 3] -->
        </port>
    </input>
    <output>
        <port id="2">
            <dim>1</dim>
            <dim>2</dim>
            <dim>3</dim>
            <dim>1</dim>
        </port>
    </output>
</layer>

Example 2: unsqueeze 0D tensor (constant) to 1D tensor

<layer ... type="Unsqueeze">
    <input>
        <port id="0">
        </port>
    </input>
    <input>
        <port id="1">
            <dim>1</dim>  <!-- value is [0] -->
        </port>
    </input>
    <output>
        <port id="2">
            <dim>1</dim>
        </port>
    </output>
</layer>