sliceLayer

R2026b

Slice layer

Since R2026b

Description

A slice layer selects elements from a specified dimension of the input data.

Creation

Syntax

layer = sliceLayer(dim,indices)

layer = sliceLayer(dim,indices,Name=name)

Description

layer = sliceLayer(dim,indices) creates a slice layer that selects the elements specified by indices from the dimension dim of the layer input.

layer = sliceLayer(dim,indices,Name=name) also sets the Name property. For example, Name="slice" specifies the layer name.

Input Arguments

dim — Dimension to slice

positive integer

Dimension to slice, specified as a positive integer.

This argument sets the Dimension property.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

indices — Slicing indices

vector of positive integers | cell array of numeric vectors

Slicing indices, specified as one of these:

• Vector of positive integers — The layer outputs a single array that corresponds to the specified indices. For example, for the vector [1 3], the layer has one output that corresponds to indices 1 and 3 of the input.

• Cell array of vectors of positive integers — The layer outputs multiple arrays that correspond to the index vectors in the cell array. For example, for the cell array {[1 3],[2 4]}, the layer has two outputs, where the first output corresponds to indices 1 and 3 of the input, and the second output corresponds to indices 2 and 4 of the input.

This argument sets the Indices property.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | cell

name — Layer name

"" (default) | character vector | string scalar

Layer name, specified as a character vector or a string scalar. For Layer array input, the trainnet and dlnetwork functions automatically assign names to unnamed layers.

This argument sets the Name property.

Data Types: char | string

Properties

Slice

Dimension — Dimension to slice

positive integer

Dimension to slice, stored as a positive integer.

This property is read-only after object creation. To set this property, use the corresponding positional input argument when you create the SliceLayer object.

Data Types: double

Indices — Slicing indices

numeric vector of positive integers | cell array of numeric vectors

Slicing indices, specified as one of these:

• Vector of positive integers — The layer outputs a single array that corresponds to the specified indices. For example, for the vector [1 3], the layer has one output that corresponds to indices 1 and 3 of the input.

• Cell array of vectors of positive integers — The layer outputs multiple arrays that correspond to the index vectors in the cell array. For example, for the cell array {[1 3],[2 4]}, the layer has two outputs, where the first output corresponds to indices 1 and 3 of the input, and the second output corresponds to indices 2 and 4 of the input.

When Indices is a numeric vector, the layer has one output with the name 'out'. When Indices is a cell array, the layer has outputs with the names 'out1', 'out2', ..., 'outN', where N is the number of elements of Indices. For example, the output 'outK' corresponds to the indices Indices(K).

This property is read-only after object creation. To set this property, use the corresponding positional input argument when you create the SliceLayer object.

Data Types: double | cell

Layer

Name — Layer name

'' (default) | character vector

Layer name, specified as a character vector. For Layer array input, the trainnet and dlnetwork functions automatically assign names to unnamed layers.

Data Types: char

NumInputs — Number of inputs

Read-only: 1 (default)

This property is read-only.

Number of inputs to the layer, represented as 1. This layer has a single input only.

Data Types: double

InputNames — Input name

Read-only: {'in'} (default)

This property is read-only.

Input name, represented as {'in'}. This layer has a single input only.

NumOutputs — Number of outputs

Read-only: positive integer

This property is read-only.

Number of outputs from the layer, represented as a positive integer.

When Indices is a numeric vector, the layer has one output with the name 'out'. When Indices is a cell array, the layer has outputs with the names 'out1', 'out2', ..., 'outN', where N is the number of elements of Indices. For example, the output 'outK' corresponds to the indices Indices(K).

Data Types: double

OutputNames — Output names

Read-only: cell array of character vectors

This property is read-only.

Output names from the layer, represented as a cell array of character vectors.

When Indices is a numeric vector, the layer has one output with the name 'out'. When Indices is a cell array, the layer has outputs with the names 'out1', 'out2', ..., 'outN', where N is the number of elements of Indices. For example, the output 'outK' corresponds to the indices Indices(K).

Data Types: cell

Examples

Create Slice Layer

Create a slice layer that selects the first and third elements from the first dimension of the layer input.

layer = sliceLayer(1,[1 3])

layer = 
  SliceLayer with properties:

         Name: ''
    Dimension: 1
      Indices: [1 3]

   Hyperparameters
    No properties.

Algorithms

Layer Input and Output Formats

Most layers in a layer array or layer graph pass data to subsequent layers as formatted dlarray objects. The format of a dlarray object is a string of characters in which each character describes the corresponding dimension of the data. The format consists of one or more of these characters:

• "S" — Spatial

• "C" — Channel

• "B" — Batch

• "T" — Time

• "U" — Unspecified

For example, you can describe 2-D image data that is represented as a 4-D array, where the first two dimensions correspond to the spatial dimensions of the images, the third dimension corresponds to the channels of the images, and the fourth dimension corresponds to the batch dimension, as having the format "SSCB" (spatial, spatial, channel, batch).

SliceLayer objects support input data of any format. The output data has the same format as the input data.

Complex Numbers

SliceLayer objects support complex-valued input and outputs. The layer applies the same underlying operation to complex-valued input as it does to real-valued input. The layer outputs complex-valued data where applicable.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

GPU Code Generation
Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Version History

Introduced in R2026b