public static void abs(int i, HiveDecimalWritable input, DecimalColumnVector outputColVector) {
    HiveDecimalWritable decWritable = outputColVector.vector[i];
    decWritable.set(input);
    decWritable.mutateAbs();
  }
Utility functions for vector operations on decimal values.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/DecimalUtil.java