Sorting by LCC numbers has been solved in most popular languages, but I couldn't 
find any example of how to do it in R, nor could I figure it out, so in case 
anyone is interested or can help, here's where I asked about it on Stack 
Overflow:

How to sort by Library of Congress Classification (LCC) number in R
https://stackoverflow.com/q/45240337/854346

Bill
--
William Denton :: Toronto, Canada   ---   Listening to Art: https://listeningtoart.org/
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