One component for each variable in the correct order
variable_types(model)
a factor with levels binary, continuous, integer
library(magrittr) model <- MIPModel() %>% add_variable(x, type = "binary") %>% add_variable(y, type = "continuous") %>% add_variable(z, type = "integer") variable_types(model)#> [1] binary continuous integer #> Levels: binary continuous integer