Unique combination of all elements from two (or more) vectors

by

this maybe what you are after

> expand.grid(a,b)
   Var1       Var2
1   ABC 2012-05-01
2   DEF 2012-05-01
3   GHI 2012-05-01
4   ABC 2012-05-02
5   DEF 2012-05-02
6   GHI 2012-05-02
7   ABC 2012-05-03
8   DEF 2012-05-03
9   GHI 2012-05-03
10  ABC 2012-05-04
11  DEF 2012-05-04
12  GHI 2012-05-04
13  ABC 2012-05-05
14  DEF 2012-05-05
15  GHI 2012-05-05

If the resulting order isn’t what you want, you can sort afterwards. If you name the arguments to expand.grid, they will become column names:

df = expand.grid(a = a, b = b)
df[order(df$a), ]

And expand.grid generalizes to any number of input columns.

More Related Contents:

  1. How to reshape data from long to wide format
  2. Grouping functions (tapply, by, aggregate) and the *apply family
  3. Reshaping multiple sets of measurement columns (wide format) into single columns (long format)
  4. Select the row with the maximum value in each group
  5. How to create a consecutive group number
  6. Finding ALL duplicate rows, including “elements with smaller subscripts”
  7. Error in if/while (condition) {: missing Value where TRUE/FALSE needed
  8. Side-by-side plots with ggplot2
  9. Error in : object of type ‘closure’ is not subsettable
  10. General suggestions for debugging in R
  11. Find the day of a week
  12. Reorder levels of a factor without changing order of values
  13. Warning message: In `…` : invalid factor level, NA generated
  14. Pasting two vectors with combinations of all vectors’ elements
  15. Rename multiple columns by names
  16. Error in : target of assignment expands to non-language object
  17. Convert integer to class Date
  18. How to unload a package without restarting R
  19. as.Date returning NA while converting from ‘ddmmmyyyy’
  20. How to load packages in R automatically?
  21. How to search for “R” materials? [closed]
  22. What is the difference between = and ==?
  23. Set default CRAN mirror permanent in R
  24. Convert a dataframe to a vector (by rows)
  25. Read SAS sas7bdat data into R
  26. What is the difference between = and == in R?
  27. Should I use a data.frame or a matrix?
  28. Variable name restrictions in R
  29. Different legend-keys inside same legend in ggplot2
  30. Plot two graphs in a same plot

Leave a Comment