Rename Dataframe Column Names in R using Previous Column Name and Regex Pattern -


i working in r first time , have been having difficulty renaming column names in dataframe (grade.data). have dataset imported csv file has column names this: student.id

grade      interactive.exercises.1..health  interactive.exercises.2..fitness  quizzes.1..week.1.quiz  quizzes.2..week.2.quiz  case.studies.1..case.study1  case.studies.2..case.study2

i able change variable names more simple, i.e. interactive.exercises.1.health interactive.exercises.1 or quizzes.1.week.1.quiz quizzes.1

so far, have tried this:

grep(".*[0-9]", names(grade.data))

but returned:

[1]  3  4  5  6  7  8  9 11 12 13 14 15 16 17 19 20 21 22 23 24 25

can me figure out going on, , write better regex expression? thank much.

it seems truncate column names after first chunk of digits.

you may use following sub solution:

names(grade.data) <- sub("^(.*?\\d+).*$", "\\1", names(grade.data))

see regex demo

details

  • ^ - start of string
  • (.*?\\d+) - group 1 (later referred \1 replacement pattern) matching 0+ chars few possible (.*?) , 1 or more digits (\d+)
  • .* - 0+ chars many possible
  • $ - end of string

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