sparklyr (version 1.8.5)

ft_regex_tokenizer: Feature Transformation -- RegexTokenizer (Transformer)

Description

A regex based tokenizer that extracts tokens either by using the provided regex pattern to split the text (default) or repeatedly matching the regex (if gaps is false). Optional parameters also allow filtering tokens using a minimal length. It returns an array of strings that can be empty.

Usage

ft_regex_tokenizer(
  x,
  input_col = NULL,
  output_col = NULL,
  gaps = TRUE,
  min_token_length = 1,
  pattern = "\\s+",
  to_lower_case = TRUE,
  uid = random_string("regex_tokenizer_"),
  ...
)

Value

The object returned depends on the class of x. If it is a spark_connection, the function returns a ml_estimator or a ml_estimator object. If it is a ml_pipeline, it will return a pipeline with the transformer or estimator appended to it. If a tbl_spark, it will return a tbl_spark with the transformation applied to it.

Arguments

x

A spark_connection, ml_pipeline, or a tbl_spark.

input_col

The name of the input column.

output_col

The name of the output column.

gaps

Indicates whether regex splits on gaps (TRUE) or matches tokens (FALSE).

min_token_length

Minimum token length, greater than or equal to 0.

pattern

The regular expression pattern to be used.

to_lower_case

Indicates whether to convert all characters to lowercase before tokenizing.

uid

A character string used to uniquely identify the feature transformer.

...

Optional arguments; currently unused.

See Also

Other feature transformers: ft_binarizer(), ft_bucketizer(), ft_chisq_selector(), ft_count_vectorizer(), ft_dct(), ft_elementwise_product(), ft_feature_hasher(), ft_hashing_tf(), ft_idf(), ft_imputer(), ft_index_to_string(), ft_interaction(), ft_lsh, ft_max_abs_scaler(), ft_min_max_scaler(), ft_ngram(), ft_normalizer(), ft_one_hot_encoder_estimator(), ft_one_hot_encoder(), ft_pca(), ft_polynomial_expansion(), ft_quantile_discretizer(), ft_r_formula(), ft_robust_scaler(), ft_sql_transformer(), ft_standard_scaler(), ft_stop_words_remover(), ft_string_indexer(), ft_tokenizer(), ft_vector_assembler(), ft_vector_indexer(), ft_vector_slicer(), ft_word2vec()