I have received a few private emails asking for some simple demonstration of calling Java code from R using the rJava package (which can be installed directly inside R). Here is one example for convolving two vectors (an example in the R manual about linking C with R).
First write a Java program public class my_convolve { public static double[] convolve(double[] a, double[] b) { int n1 = a.length; int n2 = b.length; int n3 = n1+n1-1; double[] c = new double[n3]; for(int i=0; i<n1; i++) for(int j=0; j<n2; j++) c[i+j] += a[i]*b[j]; return c; } } Compile the Java code. now inside R library(rJava) #load the rJava library .jinit(classpath="c:/liao_all/importance_sampling/java", parameters="-Xmx512m") #the above is to load the Java virtual machine, "c:/liao_all/importance_sampling/java" is where the java code is. x = runif(1000) y = runif(1000) #the above are two vectors to convolve #now you can call the Java method as z=.jcall("my_convolve", "[D", "convolve", x,y) #z stores the result Hope this helps. Jason Liao, http://www.geocities.com/jg_liao Associate Professor of Biostatistics Drexel University School of Public Health 245 N. 15th Street, Mail Stop 660 Philadelphia, PA 19102-1192 phone 215-762-3934 ____________________________________________________________________________________ Cheap talk? ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.