train.ruta_autoencoder: Train a learner object with data

In ruta: Implementation of Unsupervised Neural Architectures

Train a learner object with data

Description

This function compiles the neural network described by the learner object and trains it with the input data.

Usage

## S3 method for class 'ruta_autoencoder'
train(
  learner,
  data,
  validation_data = NULL,
  metrics = NULL,
  epochs = 20,
  optimizer = "rmsprop",
  ...
)

train(learner, ...)

Arguments

learner	A "ruta_autoencoder" object
data	Training data: columns are attributes and rows are instances
validation_data	Additional numeric data matrix which will not be used for training but the loss measure and any metrics will be computed against it
metrics	Optional list of metrics which will evaluate the model but won't be optimized. See keras::\link[keras]{compile}
epochs	The number of times data will pass through the network
optimizer	The optimizer to be used in order to train the model, can be any optimizer object defined by Keras (e.g. keras::optimizer_adam())
...	Additional parameters for keras::\link[keras]{fit}. Some useful parameters: batch_size The number of examples to be grouped for each gradient update. Use a smaller batch size for more frequent weight updates or a larger one for faster optimization. shuffle Whether to shuffle the training data before each epoch, defaults to TRUE

Value

Same autoencoder passed as parameter, with trained internal models

See Also

\link{autoencoder}

Examples

# Minimal example ================================================

if (interactive() && keras::is_keras_available())
  iris_model <- train(autoencoder(2), as.matrix(iris[, 1:4]))


# Simple example with MNIST ======================================

library(keras)
if (interactive() && keras::is_keras_available()) {
  # Load and normalize MNIST
  mnist = dataset_mnist()
  x_train <- array_reshape(
    mnist$train$x, c(dim(mnist$train$x)[1], 784)
  )
  x_train <- x_train / 255.0
  x_test <- array_reshape(
    mnist$test$x, c(dim(mnist$test$x)[1], 784)
  )
  x_test <- x_test / 255.0

  # Autoencoder with layers: 784-256-36-256-784
  learner <- autoencoder(c(256, 36), "binary_crossentropy")
  train(
    learner,
    x_train,
    epochs = 1,
    optimizer = "rmsprop",
    batch_size = 64,
    validation_data = x_test,
    metrics = list("binary_accuracy")
  )
}

ruta documentation built on Jan. 9, 2023, 1:20 a.m.