mlr_pipeops_nn_block: Block Repetition

In mlr3torch: Deep Learning with 'mlr3'

Block Repetition

Description

Repeat a block n_blocks times by concatenating it with itself (via ⁠%>>%⁠).

Naming

For the generated module graph, the IDs of the modules are generated by prefixing the IDs of the n_blocks layers with the ID of the PipeOpTorchBlock and postfixing them with ⁠__<layer>⁠.

Parameters

The parameters available for the provided block, as well as

• n_blocks :: integer(1)
  How often to repeat the block.

• trafo :: ⁠function(i, param_vals, param_set) -> list()⁠
  A function that allows to transform the parameters vaues of each layer (block). Here,

  • i :: integer(1)
    is the index of the layer, ranging from 1 to n_blocks.

  • param_vals :: named list()
    are the parameter values of the layer i.

  • param_set :: ParamSet
    is the parameter set of the whole PipeOpTorchBlock.

  The function must return the modified parameter values for the given layer. This, e.g., allows for special behavior of the first or last layer.

Input and Output Channels

The PipeOp sets its input and output channels to those from the block (Graph) it received during construction.

State

The state is the value calculated by the public method ⁠$shapes_out()⁠.

Super classes

mlr3pipelines::PipeOp -> mlr3torch::PipeOpTorch -> PipeOpTorchBlock

Active bindings

block

(Graph)
The neural network segment that is repeated by this PipeOp.

Methods

Public methods

• PipeOpTorchBlock$new()

• PipeOpTorchBlock$clone()

Inherited methods

• mlr3pipelines::PipeOp$help()
• mlr3pipelines::PipeOp$predict()
• mlr3pipelines::PipeOp$print()
• mlr3pipelines::PipeOp$train()
• mlr3torch::PipeOpTorch$shapes_out()

---

Method new()

Creates a new instance of this R6 class.

Usage

PipeOpTorchBlock$new(block, id = "nn_block", param_vals = list())

Arguments

block

(Graph)
A graph consisting primarily of PipeOpTorch objects that is to be repeated.

id

(character(1))
The id for of the new object.

param_vals

(named list())
Parameter values to be set after construction.

---

Method clone()

The objects of this class are cloneable with this method.

Usage

PipeOpTorchBlock$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

See Also

Other PipeOps: mlr_pipeops_nn_adaptive_avg_pool1d, mlr_pipeops_nn_adaptive_avg_pool2d, mlr_pipeops_nn_adaptive_avg_pool3d, mlr_pipeops_nn_avg_pool1d, mlr_pipeops_nn_avg_pool2d, mlr_pipeops_nn_avg_pool3d, mlr_pipeops_nn_batch_norm1d, mlr_pipeops_nn_batch_norm2d, mlr_pipeops_nn_batch_norm3d, mlr_pipeops_nn_celu, mlr_pipeops_nn_conv1d, mlr_pipeops_nn_conv2d, mlr_pipeops_nn_conv3d, mlr_pipeops_nn_conv_transpose1d, mlr_pipeops_nn_conv_transpose2d, mlr_pipeops_nn_conv_transpose3d, mlr_pipeops_nn_dropout, mlr_pipeops_nn_elu, mlr_pipeops_nn_flatten, mlr_pipeops_nn_ft_cls, mlr_pipeops_nn_ft_transformer_block, mlr_pipeops_nn_geglu, mlr_pipeops_nn_gelu, mlr_pipeops_nn_glu, mlr_pipeops_nn_hardshrink, mlr_pipeops_nn_hardsigmoid, mlr_pipeops_nn_hardtanh, mlr_pipeops_nn_head, mlr_pipeops_nn_identity, mlr_pipeops_nn_layer_norm, mlr_pipeops_nn_leaky_relu, mlr_pipeops_nn_linear, mlr_pipeops_nn_log_sigmoid, mlr_pipeops_nn_max_pool1d, mlr_pipeops_nn_max_pool2d, mlr_pipeops_nn_max_pool3d, mlr_pipeops_nn_merge, mlr_pipeops_nn_merge_cat, mlr_pipeops_nn_merge_prod, mlr_pipeops_nn_merge_sum, mlr_pipeops_nn_prelu, mlr_pipeops_nn_reglu, mlr_pipeops_nn_relu, mlr_pipeops_nn_relu6, mlr_pipeops_nn_reshape, mlr_pipeops_nn_rrelu, mlr_pipeops_nn_selu, mlr_pipeops_nn_sigmoid, mlr_pipeops_nn_softmax, mlr_pipeops_nn_softplus, mlr_pipeops_nn_softshrink, mlr_pipeops_nn_softsign, mlr_pipeops_nn_squeeze, mlr_pipeops_nn_tanh, mlr_pipeops_nn_tanhshrink, mlr_pipeops_nn_threshold, mlr_pipeops_nn_tokenizer_categ, mlr_pipeops_nn_tokenizer_num, mlr_pipeops_nn_unsqueeze, mlr_pipeops_torch_ingress, mlr_pipeops_torch_ingress_categ, mlr_pipeops_torch_ingress_ltnsr, mlr_pipeops_torch_ingress_num, mlr_pipeops_torch_loss, mlr_pipeops_torch_model, mlr_pipeops_torch_model_classif, mlr_pipeops_torch_model_regr

Examples

# repeat a simple linear layer with ReLU activation 3 times, but set the bias for the last
# layer to `FALSE`
block = nn("linear") %>>% nn("relu")

blocks = nn("block", block,
  linear.out_features = 10L, linear.bias = TRUE, n_blocks = 3,
  trafo = function(i, param_vals, param_set) {
    if (i  == param_set$get_values()$n_blocks) {
      param_vals$linear.bias = FALSE
    }
    param_vals
  })
graph = po("torch_ingress_num") %>>%
  blocks %>>%
  nn("head")
md = graph$train(tsk("iris"))[[1L]]
network = model_descriptor_to_module(md)
network

mlr3torch documentation built on Aug. 26, 2025, 5:09 p.m.