step_pos_filter: Part of speech filtering of tokenlist variables

Description Usage Arguments Details Value See Also Examples

View source: R/pos_filter.R

Description

step_pos_filter creates a specification of a recipe step that will filter a tokenlist based on part of speech tags.

Usage

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step_pos_filter(
  recipe,
  ...,
  role = NA,
  trained = FALSE,
  columns = NULL,
  keep_tags = "NOUN",
  skip = FALSE,
  id = rand_id("pos_filter")
)

## S3 method for class 'step_pos_filter'
tidy(x, ...)

Arguments

recipe

A recipe object. The step will be added to the sequence of operations for this recipe.

...

One or more selector functions to choose which variables are affected by the step. See recipes::selections() for more details.

role

Not used by this step since no new variables are created.

trained

A logical to indicate if the quantities for preprocessing have been estimated.

columns

A character string of variable names that will be populated (eventually) by the terms argument. This is NULL until the step is trained by recipes::prep.recipe().

keep_tags

Character variable of part of speech tags to keep. See details for complete list of tags. Defaults to "NOUN".

skip

A logical. Should the step be skipped when the recipe is baked by recipes::bake.recipe()? While all operations are baked when recipes::prep.recipe() is run, some operations may not be able to be conducted on new data (e.g. processing the outcome variable(s)). Care should be taken when using skip = FALSE.

id

A character string that is unique to this step to identify it.

x

A step_pos_filter object.

Details

Possible part of speech tags for spacyr engine are: "ADJ", "ADP", "ADV", "AUX", "CONJ", "CCONJ", "DET", "INTJ", "NOUN", "NUM", "PART", "PRON", "PROPN", "PUNCT", "SCONJ", "SYM", "VERB", "X" and "SPACE". For more information look here https://spacy.io/api/annotation#pos-tagging.

Value

An updated version of recipe with the new step added to the sequence of existing steps (if any).

See Also

step_tokenize() to turn character into tokenlist.

Other tokenlist to tokenlist steps: step_lemma(), step_ngram(), step_stem(), step_stopwords(), step_tokenfilter(), step_tokenmerge()

Examples

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## Not run: 
library(recipes)

short_data <- data.frame(text = c(
  "This is a short tale,",
  "With many cats and ladies."
))

okc_rec <- recipe(~text, data = short_data) %>%
  step_tokenize(text, engine = "spacyr") %>%
  step_pos_filter(text, keep_tags = "NOUN") %>%
  step_tf(text)

okc_obj <- prep(okc_rec)

bake(okc_obj, new_data = NULL)

## End(Not run)

textrecipes documentation built on July 11, 2021, 9:06 a.m.