code: public static void writeFloatList(IonWriter writer, float[] values)
          throws IOException
      {
          if (writer instanceof _Private_ListWriter) {
              ((_Private_ListWriter)writer).writeFloatList(values);
              return;
          }
  
          writer.stepIn(IonType.LIST);
          for (int ii=0; ii<values.length; ii++) {
              writer.writeFloat(values[ii]);
          }
          writer.stepOut();
      }
docs: writes an IonList with a series of IonFloat values. This
  starts a List, writes the values (without any annoations)
  and closes the list. For text and tree writers this is
  just a convienience, but for the binary writer it can be
  optimized internally.  Note that since, currently, IonFloat
  is a 64 bit float this is a helper that simply casts
  the passed in floats to double before writing them.
  @param values 32 bit float values to populate the lists IonFloat's with