I have been interested in studying R programming language recently and I came through this line of code which I am not understanding.
rugbyData <- rugbyHTMLData %>% html_nodes("table.wikitable") %>% .[[3]] %>% html_table
What does %>% means?
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See https://stackoverflow.com/questions/27125672/what-does-function-mean-in-r – sk877 Apr 13 '21 at 15:26
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have you tried to ask google already? https://seananderson.ca/2014/09/13/dplyr-intro/ – DPH Apr 13 '21 at 15:26
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In R, %>% is the pipe operator.
It enables you to chain operations in a data pipeline, as the output of every step becomes the input of the next step.
Without it the code would look like this:
rugbyData <- rugbyHTMLData
extracted_nodes <- html_nodes(rugbyData, "table.wikitable")
selected_node <- extracted_nodes[[3]]
final_result <- html_table(selected_node)
...code that creates 3 useless variables
Note the "." that is a placeholder to say "the piped object goes here".
It's provide by the magrittr package →Reference
NB: why magrittr ? → "Ceci n'est pas une pipe / This is not a pipe"
Cylldby
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Thank you so much for the code. Can you please comment in each line so that I can understand what it does? Because I am still a beginner in R. – Brams Abe Abey Apr 14 '21 at 08:34
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It is actually quite difficult given the lack of context, but here is what I can figure out: if I'm correct you are using the `rvest` package to scrape a web page (I'm guessing a wikipedia page about Rugby, probably IRB rankings or World Cup winners) and extracting a table from there.. I can only suggest you to look the documentation of each function used here, particularly the inputs and outputs – Cylldby Apr 14 '21 at 14:53