On 12/5/07 12:15 PM, "Prof Brian Ripley" <[EMAIL PROTECTED]> wrote:
On Wed, 5 Dec 2007, David Coppit wrote:
> Or, given that I'm dealing with just a single array, would it be better to
> roll my own I/O using write.table or write.matrix from the MASS package?
It would be much easier. The save() format is far more complex than you
need. However, I would use writeBin() to write a binary file and read
that in in Java, avoiding the binary -> ASCII -> binary conversion.
Thanks for the suggestion-writeBin works quite well. For posterity, here's what
I did:
On the R side:
# Assumes that there are no special values in the tofList, such as NA_REAL,
# R_PosInf, R_NegInf, ISNAN, R_FINITE. See the "R Data Import/Export" manual.
saveListAsBinary <- function( tofList, filename )
{
outConn <- file( filename, "wb" );
for (m in 1:length(tofList)) {
writeBin(names(tofList)[[m]], outConn);
writeBin(length(tofList[[m]]), outConn, size = 4, endian = "big");
writeBin(tofList[[m]], outConn, size = 4, endian = "big");
}
close(outConn);
}
saveListAsBinary(myList, "outfile.RDat");
On the Java side:
public static void read_R_Output(String filename, ArrayList<String> names,
ArrayList<ArrayList<Float>> data)
{
try {
DataInputStream dataInputStream = new DataInputStream(
new BufferedInputStream(new FileInputStream(filename)));
boolean endOfFile = false;
while (!endOfFile) {
try {
StringBuffer sb = new StringBuffer();
byte c;
while ((c = dataInputStream.readByte()) != 0)
sb.append((char)c);
names.add(new String(sb));
int cols = dataInputStream.readInt();
ArrayList<Float> row = new ArrayList<Float>(cols);
for (int i = 0; i < cols; i++)
row.add(dataInputStream.readFloat());
data.add(row);
} catch (EOFException e) {
endOfFile = true;
}
}
dataInputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
Regards,
David
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