README.md

In trinker/parsent: Sentence Parsing Tools

parsent

parsent is a collection of tools used to parse sentences. The package is a wrapper for the NLP/openNLP packages that simplifies and extends the user experience.

Table of Contents

• Function Usage
• Installation
• Contact
• Demonstration
  • Load the Packages/Data
  • Create Annotator
  • Parsing
  • Plotting
  • Get Subject, Verb, and Direct Object
    • Subject
    • Predicate Verb
    • Direct Object

Function Usage

Functions typically fall into the task category of (1) parsing, (2) converting, & (3) extracting. The main functions, task category, & descriptions are summarized in the table below:

Function Task Description parser parsing Parse sentences into phrases parse_annotator parsing Generate OpenNLP parser required by parser function as_tree converting Convert parser output into tree form as_square_brace converting Convert parser output in square brace form (vs. round) as_square_brace_latex converting Convert parser output LaTeX ready form get_phrases extracting Extract phrases from parser output get_phrase_type extracting Extract phrases one step down the tree get_phrase_type_regex extracting Extract phrases at any level in the tree (uses regex) get_leaves extracting Extract the leaves (tokens or words) from a phrase take extracting Select indexed elements from a vector

Installation

To download the development version of parsent:

Download the zip ball or tar ball, decompress and run R CMD INSTALL on it, or use the pacman package to install the development version:

if (!require("pacman")) install.packages("pacman")
pacman::p_load_gh(c(
    "trinker/textshape", 
    "trinker/coreNLPsetup",          
    "trinker/parsent"
))

Contact

You are welcome to: - submit suggestions and bug-reports at: https://github.com/trinker/parsent/issues - send a pull request on: https://github.com/trinker/parsent/ - compose a friendly e-mail to: [e-mail]

Demonstration

Load the Packages/Data

if (!require("pacman")) install.packages("pacman")

pacman::p_load(parsent, magrittr)

txt <- c(
    "Really, I like chocolate because it is good. It smells great.",
    "Robots are rather evil and most are devoid of decency.",
    "He is my friend.",
    "Clifford the big red dog ate my lunch.",
    "Professor Johns can not teach",
    "",
    NA
)

Create Annotator

if(!exists('parse_ann')) {
    parse_ann <- parse_annotator()
}

Parsing

(x <- parser(txt, parse.annotator = parse_ann))

## [[1]]
## [1] "(TOP (S (S (ADVP (RB Really))(, ,) (NP (PRP I)) (VP (VBP like) (NP (NN chocolate)) (SBAR (IN because) (S (NP (PRP it)) (VP (VBZ is) (ADJP (JJ good)))))))(. .) (NP (PRP It)) (VP (VBZ smells) (ADJP (JJ great)))(. .)))"
## 
## [[2]]
## [1] "(TOP (S (S (NP (NNP Robots)) (VP (VBP are) (ADJP (RB rather) (JJ evil)))) (CC and) (S (NP (RBS most)) (VP (VBP are) (ADJP (JJ devoid) (PP (IN of) (NP (NN decency))))))(. .)))"
## 
## [[3]]
## [1] "(TOP (S (NP (PRP He)) (VP (VBZ is) (NP (PRP$ my) (NN friend)))(. .)))"
## 
## [[4]]
## [1] "(TOP (S (NP (NNP Clifford)) (NP (DT the) (JJ big) (JJ red) (NN dog)) (VP (VBD ate) (NP (PRP$ my) (NN lunch)))(. .)))"
## 
## [[5]]
## [1] "(TOP (S (S (NP (NNP Professor) (NNP Johns)) (VP (MD can))) (RB not) (VB teach)))"
## 
## [[6]]
## [1] NA
## 
## [[7]]
## [1] NA

Note that the user may choose to use CoreNLP as a backend by setting engine = "coreNLP". To ensure that coreNLP is setup properly use check_setup.

Plotting

par(mar = c(0,0,0,.7) + 0.2)
plot(x[[2]])

par(
    mfrow = c(3, 2),
    mar = c(0,0,1,1) + 0.1
)
invisible(lapply(x[1:5], plot))

Get Subject, Verb, and Direct Object

Subject

get_phrase_type(x, "NP") %>%
    take() %>%
    get_leaves()

## [[1]]
## [1] "I"
## 
## [[2]]
## [1] "Robots"
## 
## [[3]]
## [1] "He"
## 
## [[4]]
## [1] "Clifford"
## 
## [[5]]
## [1] "Professor" "Johns"    
## 
## [[6]]
## [1] NA
## 
## [[7]]
## [1] NA

Predicate Verb

get_phrase_type_regex(x, "VP") %>%
    take() %>%
    get_phrase_type_regex("(VB|MD)") %>%
    take() %>%
    get_leaves()

## [[1]]
## [1] "like"
## 
## [[2]]
## [1] "are"
## 
## [[3]]
## [1] "is"
## 
## [[4]]
## [1] "ate"
## 
## [[5]]
## [1] "can"
## 
## [[6]]
## [1] NA
## 
## [[7]]
## [1] NA

Direct Object

get_phrase_type_regex(x, "VP") %>%
    take() %>%
    get_phrase_type_regex("NP") %>%
    take() %>%
    get_leaves()

## [[1]]
## [1] "chocolate"
## 
## [[2]]
## NULL
## 
## [[3]]
## [1] "my"     "friend"
## 
## [[4]]
## [1] "my"    "lunch"
## 
## [[5]]
## NULL
## 
## [[6]]
## [1] NA
## 
## [[7]]
## [1] NA

trinker/parsent documentation built on May 31, 2019, 9:41 p.m.