Build a function

You're still trying to perfect your tools for doing webs scraping to be as efficient as possible doing your job as a data analyst for a web agency.

In this exercise, you will make the extractor function from the previous exercise a little bit stricter: if the code returned by the status extractor is not between 200 and 203, the function will return a missing value (NA). In the other case, the status code will be returned.

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This exercise is part of the course

Intermediate Functional Programming with purrr

Exercise instructions

Negate the %in% operator, which is used to test if the element on the left is inside the element of the right.
Compose a extract_status() function, which will be a combination of GET() and status_code().
Complete the given function: the url status code should be extracted and assigned to a code variable. Then if this code is not in 200:203, a missing value will be returned. Otherwise, the status code is returned.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Negate the %in% function 
`%not_in%` <- ___(`%in%`)

# Compose a status extractor 
extract_status <- ___(___, ___)

# Complete the function definition
strict_code <- function(url) {
  # Extract the status of the URL
  code <- ___(___)
  # If code is not in the acceptable range ...
  if (code ___ 200:203) {
    # then return NA
    return(___)
  }
  code
}

Edit and Run Code

This exercise is part of the course

Intermediate Functional Programming with purrr

IntermediateSkill Level

4.9+

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Current Exercise

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