easyPubMed (version 2.13)

custom_grep: Retrieve Text Between XML Tags

Description

Extract text form a string containing XML or HTML tags. Text included between tags of interest will be returned. If multiple tagged substrings are found, they will be returned as different elements of a list or character vector.

Usage

custom_grep(xml_data, tag, format = "list")

Value

List or vector where each element corresponds to an in-tag substring.

Arguments

xml_data

String (of class character and length 1): corresponds to the PubMed record or any string including XML/HTML tags.

tag

String (of class character and length 1): the tag of interest (does NOT include < > chars).

format

c("list", "char"): specifies the format for the output.

Author

Damiano Fantini

Details

The input string has to be a character string (length 1) containing tags (HTML or XML format). If an XML Document is provided as input, the function will rise an error.

References

https://www.data-pulse.com/dev_site/easypubmed/

Examples

try({
  ## extract substrings based on regular expressions
  string_01 <- "I can't wait to watch the Late Night Show with" 
  string_01 <- paste(string_01, "Seth Meyers tonight at 11:30pm CT!")
  print(string_01)
  custom_grep(xml_data = string_01, tag = "strong", format = "char")
  custom_grep(xml_data = string_01, tag = "strong", format = "list")
}, silent = TRUE)