test-layers.R
In keras3: R Interface to 'Keras'

context("layers")

test_call_succeeds("layer_input", {
  layer_input(shape = c(32))
  input <- layer_input(shape = c(32), sparse = TRUE)
})

test_call_succeeds("layer_dense", {
  layer_dense(keras_model_sequential(), 32, input_shape = c(784))
})

test_call_succeeds("layer_activation", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation('relu')
})

test_call_succeeds("layer_activation_relu", required_version = "2.2.0", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation_relu()
})

test_call_succeeds("layer_activation_selu", required_version = "2.2.0", {
  skip("layer_activation_selu")
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation_selu()
})

test_call_succeeds("layer_activation_leaky_relu", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation_leaky_relu()
})

test_call_succeeds("layer_activation_parametric_relu", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation_parametric_relu()
})


test_call_succeeds("layer_activation_elu", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activation_elu()
})

test_call_succeeds("layer_activity_regularization", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_activity_regularization()
})

test_call_succeeds("layer_dropout", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_dropout(rate = 0.5, noise_shape = c(1))
})

test_call_succeeds("layer_spatial_dropout_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_spatial_dropout_1d(rate = 0.5)
})

test_call_succeeds("layer_spatial_dropout_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_spatial_dropout_2d(rate = 0.5)
})

test_call_succeeds("layer_spatial_dropout_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_spatial_dropout_3d(rate = 0.5)
})


test_call_succeeds("layer_lambda", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_lambda(function(t) t, output_shape = c(784))
})

test_call_succeeds("layer_masking", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_masking(mask_value = 0.5)
})

test_call_succeeds("layer_repeat_vector", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_repeat_vector(3)
})


test_call_succeeds("layer_reshape", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16))
})

test_call_succeeds("layer_permute", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_permute(dims = c(1))
})

test_call_succeeds("layer_flatten", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_flatten()
})

test_call_succeeds("layer_conv_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_conv_1d(filters = 3, kernel_size = 2)
})

test_call_succeeds("layer_conv_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_conv_2d(filters = 3, kernel_size = c(2, 2))
})

test_call_succeeds("layer_conv_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_conv_3d(filters = 3, kernel_size = c(2, 2, 2))
})

test_call_succeeds("layer_conv_1d_transpose", {
  if (tensorflow::tf_version() < "2.3") skip("Needs TF >= 2.3")
  keras_model_sequential() %>%
    layer_dense(32, input_shape = 100) %>%
    layer_reshape(target_shape = c(8,4)) %>%
    layer_conv_1d_transpose(filters = 3, kernel_size = 2)
})

test_call_succeeds("layer_conv_2d_transpose", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_conv_2d_transpose(filters = 3, kernel_size = c(2, 2))
})

test_call_succeeds("layer_conv_3d_transpose", required_version = "2.0.6", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_conv_3d_transpose(filters = 3, kernel_size = c(2, 2, 2))
})

test_call_succeeds("layer_separable_conv_2d", {
  if (is_tensorflow_implementation()) {
    keras_model_sequential() %>%
      layer_dense(32, input_shape = c(784)) %>%
      layer_reshape(target_shape = c(2,4,4)) %>%
      layer_separable_conv_2d(filters = 4, kernel_size = c(2,2))
  }
})


test_call_succeeds("layer_depthwise_conv_2d", required_version = "2.1.5", {
  if (is_tensorflow_implementation()) {
    keras_model_sequential() %>%
      layer_dense(32, input_shape = c(784)) %>%
      layer_reshape(target_shape = c(2,4,4)) %>%
      layer_depthwise_conv_2d(kernel_size = c(2,2))
  }
})

if(tf_version() >= "2.8")
test_call_succeeds("layer_depthwise_conv_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(4, -1)) %>%
    layer_depthwise_conv_1d(kernel_size = 2)
})

if(tf_version() >= "2.6")
test_call_succeeds("layer_conv_lstm_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_conv_lstm_1d(filters = 3, kernel_size = c(2))
})

test_call_succeeds("layer_conv_lstm_2d", {
  keras_model_sequential() %>%
    layer_dense(16, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,2)) %>%
    layer_conv_lstm_2d(filters = 3, kernel_size = c(1, 1))
})

if(tf_version() >= "2.6")
test_call_succeeds("layer_conv_lstm_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,2,2)) %>%
    layer_conv_lstm_3d(filters = 3, kernel_size = c(1, 1, 2))
})

test_call_succeeds("layer_upsampling_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_upsampling_1d()
})

test_call_succeeds("layer_upsampling_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_upsampling_2d()
})

test_call_succeeds("layer_upsampling_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,2,2)) %>%
    layer_upsampling_3d()

})


test_call_succeeds("layer_zero_padding_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_zero_padding_1d()
})

test_call_succeeds("layer_zero_padding_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_zero_padding_2d()
})


test_call_succeeds("layer_zero_padding_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,2,2)) %>%
    layer_zero_padding_3d()
})


test_call_succeeds("layer_cropping_1d", {
  skip_if_cntk() # crashes CNTK
  keras_model_sequential() %>%
    layer_dense(64, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(4,16)) %>%
    layer_cropping_1d()
})

test_call_succeeds("layer_cropping_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_cropping_2d()
})


test_call_succeeds("layer_cropping_3d", {
  keras_model_sequential() %>%
    layer_dense(32*4, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(4,4,4,2)) %>%
    layer_cropping_3d()
})

test_call_succeeds("layer_max_pooling_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_max_pooling_1d()
})

test_call_succeeds("layer_max_pooling_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_max_pooling_2d()
})


test_call_succeeds("layer_max_pooling_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_max_pooling_3d()
})

test_call_succeeds("layer_average_pooling_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_average_pooling_1d(2)
})

test_call_succeeds("layer_average_pooling_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_average_pooling_2d(c(2, 2))
})


test_call_succeeds("layer_average_pooling_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_average_pooling_3d(c(2, 2, 2))
})

test_call_succeeds("layer_global_average_pooling_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_global_average_pooling_1d()
})

test_call_succeeds("layer_global_average_pooling_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_global_average_pooling_2d()
})


test_call_succeeds("layer_global_average_pooling_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_global_average_pooling_3d()
})

test_call_succeeds("layer_global_max_pooling_1d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_global_max_pooling_1d()
})

test_call_succeeds("layer_global_max_pooling_2d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,4,4)) %>%
    layer_global_max_pooling_2d()
})


test_call_succeeds("layer_global_max_pooling_3d", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,2,2,4)) %>%
    layer_global_max_pooling_3d()
})


test_call_succeeds("layer_simple_rnn", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_simple_rnn(units = 2)
})

test_call_succeeds("layer_gru", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_gru(units = 2)
})

test_call_succeeds("layer_lstm", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_lstm(units = 2)
})

test_call_succeeds("layer_embedding", {
  skip("layer_embedding() upstream doc example errors")
  keras_model_sequential() %>%
    layer_embedding(1000, 64, input_length = 10)
})

get_merge_inputs <- function() {
  c(layer_input(shape = c(4, 5)),
    layer_input(shape = c(4, 5)),
    layer_input(shape = c(4, 5)))
}


test_call_succeeds("layer_add", {
  merge_inputs <- get_merge_inputs()
  output <- layer_add(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_add()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds(required_version = "2.0.7", "layer_subtract", {
  merge_inputs <- c(layer_input(shape = c(4, 5)),
                    layer_input(shape = c(4, 5)))
  output <- layer_subtract(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_subtract()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_multiply", {
  merge_inputs <- get_merge_inputs()
  output <- layer_multiply(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_multiply()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_maximum", {
  merge_inputs <- get_merge_inputs()
  output <- layer_maximum(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_maximum()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_minumum", required_version = "2.0.9", {
  merge_inputs <- get_merge_inputs()
  output <- layer_minimum(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_minimum()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_average", {
  merge_inputs <- get_merge_inputs()
  output <- layer_average(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_average()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_concatenate", {
  merge_inputs <- get_merge_inputs()
  output <- layer_concatenate(merge_inputs)
  keras_model(merge_inputs, output)

  output <- layer_concatenate()(merge_inputs)
  keras_model(merge_inputs, output)
})

test_call_succeeds("layer_batch_normalization", {
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_batch_normalization()
})

test_call_succeeds("layer_gaussian_noise", {
  skip_if_cntk()
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_gaussian_noise(stddev = 0.5)
})

test_call_succeeds("layer_gaussian_dropout", {
  skip_if_cntk()
  keras_model_sequential() %>%
    layer_dense(32, input_shape = c(784)) %>%
    layer_reshape(target_shape = c(2,16)) %>%
    layer_gaussian_dropout(rate = 0.5)
})


test_call_succeeds("time_distributed", {
  keras_model_sequential() %>%
    time_distributed(layer_dense(units = 8), input_shape = c(10, 16))
})

test_call_succeeds("bidirectional", {
  keras_model_sequential() %>%
    bidirectional(layer_lstm(units = 10, return_sequences = TRUE), input_shape = c(5, 10)) %>%
    bidirectional(layer_lstm(units = 10)) %>%
    layer_dense(units = 5) %>%
    layer_activation(activation = "softmax")
})

test_call_succeeds("layer_activation_softmax", required_version = "2.1.3", {
  if (is_tensorflow_implementation()) {
    keras_model_sequential() %>%
      layer_dense(32, input_shape = c(784)) %>%
      layer_activation_softmax()
  }
})

test_call_succeeds("layer_separable_conv_1d", required_version = "2.1.3", {
  if (is_tensorflow_implementation()) {
    keras_model_sequential() %>%
      layer_dense(32, input_shape = c(784)) %>%
      layer_reshape(target_shape = c(4, 8)) %>%
      layer_separable_conv_1d(filters = 4, kernel_size = c(4))
  }
})

test_call_succeeds('layer_attention',{
  if (is_tensorflow_implementation() && tensorflow::tf_version() >= "1.14"){
    input_1 = layer_input(shape=c(4,5))
    input_2 = layer_input(shape=c(4,5))
    layer_attention(c(input_1,input_2))
  }
})

test_call_succeeds("layer_dense_features", required_version = "2.1.3", {
  if (is_tensorflow_implementation() && tensorflow::tf_version() >= "1.14") {

    # functional style

    fc <- list(tensorflow::tf$feature_column$numeric_column("mpg"))

    input <- list(mpg = layer_input(1))

    out <- input %>%
      layer_dense_features(feature_columns = fc)

    # sequential: needs to pass a list in the begining.
    feature_layer <- layer_dense_features(feature_columns = fc)

    model <- keras_model_sequential(list(
      feature_layer,
      layer_dense(units = 1)
    ))

    model %>% compile(loss = "mae", optimizer = "adam")

    model %>% fit(x = list(mpg = 1:10), y = 1:10, verbose = 0)
  }
})


test_merge_layers <- function(layer_merge, ...) {

  test_call_succeeds(deparse(substitute(layer_merge)), {

    merge_inputs <- get_merge_inputs()[1:2]
    # supplied as a list to constructor
    output <- layer_merge(merge_inputs, ...)
    keras_model(merge_inputs, output)

    # supplied as individual args to the constructor
    output <- do.call(layer_merge, c(merge_inputs, ...))
    keras_model(merge_inputs, output)

    # instantiate, then call with a list
    output <- layer_merge(...)(merge_inputs)
    keras_model(merge_inputs, output)

  })

}

test_merge_layers(layer_add)
test_merge_layers(layer_subtract)
test_merge_layers(layer_multiply)
test_merge_layers(layer_average)
test_merge_layers(layer_maximum)
test_merge_layers(layer_minimum)
test_merge_layers(layer_concatenate)
test_merge_layers(layer_concatenate, axis = 1)
test_merge_layers(layer_concatenate, axis = 2)
test_merge_layers(layer_concatenate, axis = -1)
test_merge_layers(layer_concatenate, axis = -2)
test_merge_layers(layer_dot, axes = 2)
test_merge_layers(layer_dot, axes = 2, normalize = TRUE)