Sorting With data.table Versus dplyr

Kevin Feasel

2018-08-14

R

John Mount shows us that data.table is way faster for sorting than dplyr‘s arrange function:

Notice on the above semi-log plot the run time ratio is growing roughly linearly. This makes sense: data.table uses a radix sort which has the potential to perform in near linear time (faster than the n log(n) lower bound known comparison sorting) for a range of problems (also we are only showing example sorting times, not worst-case sorting times).

In fact, if we divide the y in the above graph by log(rows) we get something approaching a constant.

John has also provided us with a markdown document for comparison.

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