tidyfst (version 1.8.1)

dummy_dt: Fast creation of dummy variables

Description

Quickly create dummy (binary) columns from character and factor type columns in the inputted data (and numeric columns if specified.) This function is useful for statistical analysis when you want binary columns rather than character columns.

Usage

dummy_dt(.data, ..., longname = TRUE)

Value

data.table

Arguments

.data

data.frame

...

Columns you want to create dummy variables from. Very flexible, find in the examples.

longname

logical. Should the output column labeled with the original column name? Default uses TRUE.

Details

If no columns provided, will return the original data frame. When NA exist in the input column, they would also be considered. If the input character column contains both NA and string "NA", they would be merged.

This function is inspired by fastDummies package, but provides simple and precise usage, whereas fastDummies::dummy_cols provides more features for statistical usage.

References

https://stackoverflow.com/questions/18881073/creating-dummy-variables-in-r-data-table

See Also

dummy_cols

Examples

iris %>% dummy_dt(Species)
iris %>% dummy_dt(Species,longname = FALSE)

mtcars %>% head() %>% dummy_dt(vs,am)
mtcars %>% head() %>% dummy_dt("cyl|gear")

# when there are NAs in the column
df <- data.table(x = c("a", "b", NA, NA),y = 1:4)
df %>%
  dummy_dt(x)

# when NA  and "NA" both exist, they would be merged
df <- data.table(x = c("a", "b", NA, "NA"),y = 1:4)
df %>%
  dummy_dt(x)