re.rniAssign("a", xp1, 0);
// Example: how to create a named list or data.frame
double da[] = {1.2, 2.3, 4.5};
double db[] = {1.4, 2.6, 4.2};
long xp3 = re.rniPutDoubleArray(da);
long xp4 = re.rniPutDoubleArray(db);
// now build a list (generic vector is how that's called in R)
long la[] = {xp3, xp4};
long xp5 = re.rniPutVector(la);