R/utils.R

In canfielder/CausalityExtraction: Hypothesis Extraction and Analysis for Scholarly Papers in Social Sciences

#' Generate regex expression from string
#'
#' @param input.str text to be converted to regex expression
#' @param match flag indicating if conversion should look for exact or partial
#'  match of regex expression
#' @noRd

gen_regex <- function(input.str, match){
  # Initialize
  input.str_exact <- c()

  if (match == "exact"){
    for (item in input.str){
      item_exact <- paste0("^",item,"$")
      input.str_exact <- append(input.str_exact, item_exact)

    }
    # Reassign input variable
    input.str <- input.str_exact

  }
  regex_string <- paste0("\\b(", paste(input.str, collapse="|"), ")\\b")

  regex_string
}


#' Verify input is not null
#'
#' Returns a boolean verifying is the provided input is not null
#'
#' @param x input
#' @noRd

is.not.null <- function(x) !is.null(x)


#' Inspect text vector.
#' 
#' Outputs useful information for inspecting a character vector.
#' This is to be used in the testing and debugging of 
#' text conversion processing.
#' 
#' @param input_text input text vector
#' @param start_index index to start inspection
#' @param span length of character vector to inspect
#' @noRd

inspect_text_vector <- function(
  input_text, 
  start_index = 100, 
  span = 20
  ) {
  # Print total vector length
  print(paste("Text Vector Length: ", length(input_text)))
  cat("\n\n")
  
  # Subset character vector
  end_index = start_index + span - 1
  input_text[start_index:end_index]
}