[Solved] Selecting a unique value from an R data frame

by


Using data.table:

(Edited to reflect @Frank’s comments)

DT[, Benchmark := Value[Category == "Time"][which.min(Number[Category == "Time"])], by = FileName]

Breaking this down:

Number[Category == "Time"]

  • Take all Number where Category == Time

which.min(^^^)

  • Find which one is the minimum

Benchmark := Value[Category == "Time"][^^^]

  • Set the new column of benchmark to the value at this minimum

by = FileName

  • Do this by group

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solved Selecting a unique value from an R data frame