There is a package foreign
with a function write.foreign()
that can write a SPS and CSV file. The SPS file than can read the CSV fiel into SPSS including labels. Fine so far, but there are some issues with that function:
- Newer SPSS versions may show an error that you have too few format definitions in
DATA LIST
- If there are "labels" for numeric variables stored via
attr()
, these are lost.
- Even if the SPSS vesion supports strings up to 32767, the function
write.foreign()
stops if there are more than 255 in any variable.
- Theres a star (*) if any character variables are used, but newer SPSS versions cannot handle that.
- The CSV file is comma-separated and does (can) not use quotes, therefore no commas are allowed in strings (character)
- Non-ASCII caracters (e.g. umlauts) will crash the import
- Should you have a character that contains any NA value, you'll see...
... an error message like this:
Error in if (any(lengths > 255L)) stop("Cannot handle character variables longer than 255") :
missing value where TRUE/FALSE needed
I spent a lot of time with that and then found a good posting (http://r.789695.n4.nabble.com/SPSS-export-in-R-package-foreign-td921491.html) to start on and make it better. Here's my result, I'd like to share with you.
This function is a replacement for foreign:write.foreign
to handle the issues stated above.
Note: To avoid issues with SPSS finding the CSV file, please specify the full path (!) at least for datafile
(also if using the original foreign:write.foreign()
).
Note: This script will replace a tabulator (TAB) and other spacing (incl. CR+LF) in strings by a blank without warning. One may consider using GET DATA
instead of the troublesome DATA LIST
to solve that limitation.
Note: There may be a warning In FUN(X[[i]], ...) : probable complete loss of accuracy in modulus
- this refers to counting the decimals and can be ignored.
Note: POSIXlt
and POSIXct
variables are not yet handled by the script properly.
writeForeignMySPSS = function (df, datafile, codefile, varnames = NULL, len = 32767) {
adQuote <- function (x) paste("\"", x, "\"", sep = "")
# Last variable must not be empty for DATA LIST
if (any(is.na(df[[length(df)]]))) {
df$END_CASE = 0
}
# http://stackoverflow.com/questions/5173692/how-to-return-number-of-decimal-places-in-r
decimalplaces <- function(x) {
y = x[!is.na(x)]
if (length(y) == 0) {
return(0)
}
if (any((y %% 1) != 0)) {
info = strsplit(sub('0+$', '', as.character(y)), ".", fixed=TRUE)
info = info[sapply(info, FUN=length) == 2]
if (length(info) >= 2) {
dec = nchar(unlist(info))[seq(2, length(info), 2)]
} else {
return(0)
}
return(max(dec, na.rm=T))
} else {
return(0)
}
}
dfn <- lapply(df, function(x) if (is.factor(x))
as.numeric(x)
else x)
# Boolean variables (dummy coding)
bv = sapply(dfn, is.logical)
for (v in which(bv)) {
dfn[[v]] = ifelse(dfn[[v]], 1, 0)
}
varlabels <- names(df)
# Use comments where applicable
for (i in 1:length(df)) {
cm = comment(df[[i]])
if (is.character(cm) && (length(cm) > 0)) {
varlabels[i] = comment(df[[i]])
}
}
if (is.null(varnames)) {
varnames <- abbreviate(names(df), 8L)
if (any(sapply(varnames, nchar) > 8L))
stop("I cannot abbreviate the variable names to eight or fewer letters")
if (any(varnames != varlabels))
warning("some variable names were abbreviated")
}
varnames <- gsub("[^[:alnum:]_\\$@#]", "\\.", varnames)
dl.varnames <- varnames
chv = sapply(df, is.character)
if (any(chv)) {
for (v in which(chv)) {
dfn[[v]] = gsub("\\s", " ", dfn[[v]])
}
lengths <- sapply(df[chv], function(v) max(nchar(v), na.rm=T))
if (any(lengths > len)) {
warning(paste("Clipped strings in", names(df[chv]), "to", len, "characters"))
for (v in which(chv)) {
df[[v]] = substr(df[[v]], start=1, stop=len)
}
}
lengths[is.infinite(lengths)] = 0
lengths[lengths < 1] = 1
lengths <- paste("(A", lengths, ")", sep = "")
# star <- ifelse(c(FALSE, diff(which(chv) > 1)), " *",
dl.varnames[chv] <- paste(dl.varnames[chv], lengths)
}
# decimals and bools
nmv = sapply(df, is.numeric)
dbv = sapply(df, is.numeric)
nv = (nmv | dbv)
decimals = sapply(df[nv], FUN=decimalplaces)
dl.varnames[nv] = paste(dl.varnames[nv], " (F", decimals+8, ".", decimals, ")", sep="")
if (length(bv) > 0) {
dl.varnames[bv] = paste(dl.varnames[bv], "(F1.0)")
}
rmv = !(chv | nv | bv)
if (length(rmv) > 0) {
dl.varnames[rmv] = paste(dl.varnames[rmv], "(F8.0)")
}
# Breaks in output
brv = seq(1, length(dl.varnames), 10)
dl.varnames[brv] = paste(dl.varnames[brv], "\n", sep=" ")
cat("SET LOCALE = ENGLISH.\n", file = codefile)
cat("DATA LIST FILE=", adQuote(datafile), " free (TAB)\n", file = codefile, append = TRUE)
cat("/", dl.varnames, " .\n\n", file = codefile, append = TRUE)
cat("VARIABLE LABELS\n", file = codefile, append = TRUE)
cat(paste(varnames, adQuote(varlabels), "\n"), ".\n", file = codefile,
append = TRUE)
factors <- sapply(df, is.factor)
if (any(factors)) {
cat("\nVALUE LABELS\n", file = codefile, append = TRUE)
for (v in which(factors)) {
cat("/\n", file = codefile, append = TRUE)
cat(varnames[v], " \n", file = codefile, append = TRUE)
levs <- levels(df[[v]])
cat(paste(1:length(levs), adQuote(levs), "\n", sep = " "),
file = codefile, append = TRUE)
}
cat(".\n", file = codefile, append = TRUE)
}
# Labels stored in attr()
attribs <- !unlist(lapply(sapply(df, FUN=attr, which="1"), FUN=is.null))
if (any(attribs)) {
cat("\nVALUE LABELS\n", file = codefile, append = TRUE)
for (v in which(attribs)) {
cat("/\n", file = codefile, append = TRUE)
cat(varnames[v], " \n", file = codefile, append = TRUE)
# Check labeled values
tc = list()
for (tcv in dimnames(table(df[[v]]))[[1]]) {
if (!is.null(tcl <- attr(df[[v]], tcv))) {
tc[tcv] = tcl
}
}
cat(paste(names(tc), tc, "\n", sep = " "),
file = codefile, append = TRUE)
}
cat(".\n", file = codefile, append = TRUE)
}
ordinal <- sapply(df, is.ordered)
if (any(ordinal)) {
tmp = varnames[ordinal]
brv = seq(1, length(tmp), 10)
tmp[brv] = paste(tmp[brv], "\n")
cat(paste("\nVARIABLE LEVEL", paste(tmp, collapse=" "), "(ORDINAL).\n"),
file = codefile, append = TRUE)
}
num <- sapply(df, is.numeric)
if (any(num)) {
tmp = varnames[num]
brv = seq(1, length(tmp), 10)
tmp[brv] = paste(tmp[brv], "\n")
cat(paste("\nVARIABLE LEVEL", paste(tmp, collapse=" "), "(SCALE).\n"),
file = codefile, append = TRUE)
}
cat("\nEXECUTE.\n", file = codefile, append = TRUE)
write.table(dfn, file = datafile, row = FALSE, col = FALSE,
sep = "\t", quote = F, na = "", eol = "\n", fileEncoding="UTF-8")
}
On the long term, the changes might be considered to be merged into the foreign
package. Unfortunately, the bug reporting system for the r-project is currently limited to previously registered developers.