code: public static float decodeFloatDesc(byte[] src, int srcOffset)
          throws CorruptEncodingException
      {
          int bits = DataDecoder.decodeFloatBits(src, srcOffset);
          if (bits >= 0) {
              bits ^= 0x7fffffff;
          }
          return Float.intBitsToFloat(bits);
      }
docs: Decodes a float from exactly 4 bytes, as encoded for descending order.
  
  @param src source of encoded bytes
  @param srcOffset offset into source array
  @return float value