String getFileName(double lat, double lon) {
        int lonInt = getMinLonForTile(lon);
        int latInt = getMinLatForTile(lat);
        return toLowerCase(getLatString(latInt) + getNorthString(latInt) + getLonString(lonInt) + getEastString(lonInt) + FILE_NAME_END);
    }
@Disabled
    @Test
    public void testGetEleVerticalBorder() {
        // Border between the tiles 50n000e and 70n000e
        assertEquals("50n000e_20101117_gmted_mea075", instance.getFileName(69.999999, 19.493));
        assertEquals(268, instance.getEle(69.999999, 19.5249), precision);
        assertEquals("70n000e_20101117_gmted_mea075", instance.getFileName(70, 19.493));
        assertEquals(298, instance.getEle(70, 19.5249), precision);
        // Second location at the border
        assertEquals("50n000e_20101117_gmted_mea075", instance.getFileName(69.999999, 19.236));
        assertEquals(245, instance.getEle(69.999999, 19.236), precision);
        assertEquals("70n000e_20101117_gmted_mea075", instance.getFileName(70, 19.236));
        assertEquals(241, instance.getEle(70, 19.236), precision);
    }