There are eight fundamental data modes in R which are ordered:
| 1 | logical (TRUE, FALSE, NA) |
| 2 | numeric (double precision and integer) |
| 3 | character (character strings) |
| 4 | complex |
| 5 | factor |
| 6 | ordered factor |
| 7 | list (includes dataframes) |
| 8 | function |
Use the R function mode to see the mode of an R function. To test if an object x is numeric: is.numeric(x). If x is numeric and you want it complex, you can use as.complex(x). Similar function prefixed by is and as exist for all other modes.