| write.dbf {foreign} | R Documentation |
The function tries to write a data frame to a DBF file.
write.dbf(dataframe, file, factor2char = TRUE)
dataframe |
a data frame object. |
file |
a file name to be written to. |
factor2char |
logical, default TRUE, convert factor columns to
character: otherwise they are written as the internal integer codes. |
Dots in column names are replaced by underlines in the DBF file, and names are truncated to 11 characters.
Only vector columns of classes "logical", "numeric",
"integer", "character", "factor" and
"Date" can be written. Other columns should be converted to
one of these.
Maximum precision (number of digits including minus sign and decimal sign) for numeric is 19 - scale (digits after the decimal sign) which is calculated internally based on the number of digits before the decimal sign.
Invisible NULL.
Other applications have varying abilities to read the data types used
here. Microsoft Access read "numeric", "integer",
"character" and "Date" fields, including recognizing
missing values, but not "logical" (read as 0,-1).
Microsoft Excel understood all possible types but did not interpret missing
values in character fields correctly (showing them as character nuls).
Nicholas J. Lewin-Koh, modified by Roger Bivand and Brian Ripley; shapelib by Frank Warmerdam.
str(warpbreaks) try1 <- paste(tempfile(), ".dbf", sep = "") write.dbf(warpbreaks, try1, factor2char = FALSE) in1 <- read.dbf(try1) str(in1) try2 <- paste(tempfile(), ".dbf", sep = "") write.dbf(warpbreaks, try2, factor2char = TRUE) in2 <- read.dbf(try2) str(in2) unlink(c(try1, try2))