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Exercise

Using .SD (I)

.SD together with .SDcols is an incredibly powerful feature that makes computing on multiple columns so much easier.

  • .SD is a special symbol which stands for Subset of Data
  • .SDcols holds the columns that should be included in .SD
Instructions
100 XP
  • For each month, find the row corresponding to the shortest trip (by using which.min() on duration).
  • The result should contain the month, start_station, end_station, start_date, end_date, and duration columns.
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