dplyr: how to reference columns by column index rather than column name using mutate?

by

You can try:

iris %>% head %>% mutate(sum = .[[1]] + .[[2]])

  Sepal.Length Sepal.Width Petal.Length Petal.Width Species sum
1          5.1         3.5          1.4         0.2  setosa 8.6
2          4.9         3.0          1.4         0.2  setosa 7.9
3          4.7         3.2          1.3         0.2  setosa 7.9
4          4.6         3.1          1.5         0.2  setosa 7.7
5          5.0         3.6          1.4         0.2  setosa 8.6
6          5.4         3.9          1.7         0.4  setosa 9.3

More Related Contents:

  1. Summarizing multiple columns with dplyr? [duplicate]
  2. Relative frequencies / proportions with dplyr
  3. Unique rows, considering two columns, in R, without order
  4. standard evaluation in dplyr: summarise a variable given as a character string
  5. dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
  6. dplyr: inner_join with a partial string match
  7. Use variable names in functions of dplyr
  8. Create new variables with mutate_at while keeping the original ones
  9. How to interpret dplyr message `summarise()` regrouping output by ‘x’ (override with `.groups` argument)?
  10. Finding percentage in a sub-group using group_by and summarise
  11. Make a group_indices based on several columns
  12. Using spread with duplicate identifiers for rows
  13. filter for complete cases in data.frame using dplyr (case-wise deletion)
  14. dplyr filter with condition on multiple columns
  15. Efficient way to filter one data frame by ranges in another
  16. Change value of variable with dplyr
  17. sample rows of subgroups from dataframe with dplyr
  18. Assigning Dates to Fiscal Year
  19. filter function in dplyr errors: object ‘name’ not found
  20. Create a ranking variable with dplyr?
  21. How to pass dynamic column names in dplyr into custom function?
  22. R – Group by variable and then assign a unique ID [duplicate]
  23. R: x ‘probs’ outside [0,1]
  24. R sum a variable by two groups [duplicate]
  25. Join two data frames in R based on closest timestamp
  26. data.table row-wise sum, mean, min, max like dplyr?
  27. Update/Replace Values in Dataframe with Tidyverse Join
  28. dplyr: put count occurrences into new variable [duplicate]
  29. Add row in each group using dplyr and add_row()
  30. How to replace certain values in a specific rows and columns with NA in R?

Leave a Comment