tfdatasets (version 2.17.0)

choose_from_datasets: Creates a dataset that deterministically chooses elements from datasets.

Description

Creates a dataset that deterministically chooses elements from datasets.

Usage

choose_from_datasets(datasets, choice_dataset, stop_on_empty_dataset = TRUE)

Value

Returns a dataset that interleaves elements from datasets according to the values of choice_dataset.

Arguments

datasets

A non-empty list of tf.data.Dataset objects with compatible structure.

choice_dataset

A tf.data.Dataset of scalar tf.int64 tensors between 0 and length(datasets) - 1.

stop_on_empty_dataset

If TRUE, selection stops if it encounters an empty dataset. If FALSE, it skips empty datasets. It is recommended to set it to TRUE. Otherwise, the selected elements start off as the user intends, but may change as input datasets become empty. This can be difficult to detect since the dataset starts off looking correct. Defaults to TRUE.

Examples

if (FALSE) {
datasets <- list(tensors_dataset("foo") %>% dataset_repeat(),
                 tensors_dataset("bar") %>% dataset_repeat(),
                 tensors_dataset("baz") %>% dataset_repeat())

# Define a dataset containing `[0, 1, 2, 0, 1, 2, 0, 1, 2]`.
choice_dataset <- range_dataset(0, 3) %>% dataset_repeat(3)
result <- choose_from_datasets(datasets, choice_dataset)
result %>% as_array_iterator() %>% iterate(function(s) s$decode()) %>% print()
# [1] "foo" "bar" "baz" "foo" "bar" "baz" "foo" "bar" "baz"
}