cdm/src/main/java/ucar/nc2/units/SimpleUnit.java
static public boolean isCompatible(String unitString1, String unitString2) {
    Unit uu1, uu2;
    try {
      UnitFormat format = UnitFormatManager.instance();
      uu1 = format.parse(unitString1);
    } catch (Exception e) {
      if (debugParse) System.out.println("Parse " + unitString1 + " got Exception1 " + e);
      return false;
    }

    try {
      UnitFormat format = UnitFormatManager.instance();
      uu2 = format.parse(unitString2);
    } catch (Exception e) {
      if (debugParse) System.out.println("Parse " + unitString2 + " got Exception2 " + e);
      return false;
    }

    //System.out.println("udunits isCompatible "+ uu1+ " "+ uu2);
    return uu1.isCompatible(uu2);
  }
static public boolean isCompatible(String unitString1, String unitString2) {
    Unit uu1, uu2;
    try {
      UnitFormat format = UnitFormatManager.instance();
      uu1 = format.parse(unitString1);
    } catch (Exception e) {
      if (debugParse) System.out.println("Parse " + unitString1 + " got Exception1 " + e);
      return false;
    }

    try {
      UnitFormat format = UnitFormatManager.instance();
      uu2 = format.parse(unitString2);
    } catch (Exception e) {
      if (debugParse) System.out.println("Parse " + unitString2 + " got Exception2 " + e);
      return false;
    }

    //System.out.println("udunits isCompatible "+ uu1+ " "+ uu2);
    return uu1.isCompatible(uu2);
  }
Return true if unitString1 is compatible to unitString2, meaning one can be converted to the other.
If either unit string is illegal, return false.

@param unitString1 compare this unit
@param unitString2 compare this unit
@return true if the 2 units are compatible