The write.fcat function writes a format catalog to the file system. By default, the catalog will be written to the current working directory, using the variable name as the file name. These defaults can be overridden using the appropriate parameters. The catalog will be saved with a file extension of ".fcat".

Note that the format catalog is saved as an RDS file. The ".fcat" file extension only serves to distinguish the format catalog from other RDS files.

write.fcat(x, dir_path = getwd(), file_name = NULL)



The format catalog to write.


The directory path to write the catalog to. Default is the current working directory.


The name of the file to save the catalog as. Default is the name of the variable that contains the catalog. The ".fcat" file extension will be added automatically.


The full path of the saved format catalog.

See also


# Create format catalog
c1 <- fcat(num_fmt  = "%.1f",
           label_fmt = value(condition(x == "A", "Label A"),
                             condition(x == "B", "Label B"),
                             condition(TRUE, "Other")),
           date_fmt = "%d%b%Y")
# Get temp directory
tmp <- tempdir()            
# Save catalog to file system
pth <- write.fcat(c1, dir_path = tmp)

# Read from file system
c2 <- read.fcat(pth)

# Use formats in the catalog
fapply(2, c1$num_fmt)
fapply(c("A", "B", "C", "B"), c1$label_fmt)
fapply(Sys.Date(), c1$date_fmt)