defaults to 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
list (or concatenation) of characters to filter out, such as
punctuation. Default: !"#$%&()*+,-./:;<=>?@[\\]^_`{|}~\\t\\n,
includes basic punctuation, tabs, and newlines.
lower
boolean. Whether to set the text to lowercase.
split
str. Separator for word splitting.
analyzer
function. Custom analyzer to split the text
Returns
A list of integer word indices (unicity non-guaranteed).
0 is a reserved index that won't be assigned to any word.
Two or more words may be assigned to the same index, due to possible
collisions by the hashing function.
The probability
of a collision is in relation to the dimension of the hashing space and
the number of distinct objects.