code: public final void multiplyValues(double multiplier) {
          for(Map.Entry<Object, Object> entry : internalData.entrySet()) {
              Double previousValue = TypeInference.toDouble(entry.getValue());
              if(previousValue==null) {
                  continue;
              }
              internalData.put(entry.getKey(), previousValue*multiplier);
          } 
      }
docs: Multiplies the values of the object with a particular multiplier. All the columns
  of this object should be numeric or boolean or else an exception is thrown.
  
  @param multiplier