SpatialReference sr2 = new SpatialReference();
sr2.ImportFromEPSG(32631);
Vector options = new Vector();
options.add("SRC_SRS=" + sr1.ExportToWkt());
options.add("DST_SRS=" + sr2.ExportToWkt());
Transformer t = new Transformer(ds1, ds2, options);
double argout[] = new double[3];
argout[0] = 0;
argout[1] = 0;
int ret = t.TransformPoint(0, argout);