Converts a text to a sequence of indexes in a fixed-size hashing space.

Converts a text to a sequence of indexes in a fixed-size hashing space.

text_hashing_trick(text, n, hash_function = NULL,
  filters = "!\"#$%&()*+,-./:;<=>?@[\\]^_`{|}~\t\n", lower = TRUE,
  split = " ")

Arguments

text

Input text (string).

n

Dimension of the hashing space.

hash_function

if NULL uses python hash function, can be 'md5' or any function that takes in input a string and returns a int. Note that hash is not a stable hashing function, so it is not consistent across different runs, while 'md5' is a stable hashing function.

filters

Sequence of characters to filter out such as punctuation. Default includes basic punctuation, tabs, and newlines.

lower

Whether to convert the input to lowercase.

split

Sentence split marker (string).

Value

A list of integer word indices (unicity non-guaranteed).

Details

Two or more words may be assigned to the same index, due to possible collisions by the hashing function.

See also

Other text preprocessing: make_sampling_table, pad_sequences, skipgrams, text_one_hot, text_to_word_sequence