@Test
public void testReadGn() throws IllegalCeosFormatException, IOException {

    _ios.writeBytes("-1.06962770630708111E+01");
    _ios.seek(0);
    final CeosFileReader ceosReader = new CeosFileReader(_ios);
    assertEquals(-1.06962770630708111E+01, ceosReader.readGn(24), 1E-25);
}