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Exercise

Playing with URLs

In the last exercise, we've extracted the raw number of tweets which contain the pattern "github". So far, this is just a raw number: 347, and you're still not able to determine which proportion of the total number of URLs this 347 represents.

In this exercise, we'll build a function called str_prop_detected(), which takes a character vector and a pattern, and returns the proportion of elements which contain this pattern. This function could be used on other datasets to detect the proportion of pattern matches in a character vector.

Here, we'll combine some purrr functions with the str_detect() function from stringr. These two packages have been loaded for you, and the rstudioconf dataset is still available in your workspace.

Instructions 1/2

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  • Complete the definition of str_prop_detected(). Use str_detect() to detect which values of string contain pattern, and calculate the mean of the occurrences.
  • Combine flatten() and compact() as flatten_and_compact().