def format_SQLtable_name(coord,units='metric'):
    """
    format string from the input coordinates dictionary, that will be suitable as MySQL table name 
    """
    if coord['lat']<0:
        lat_str = ('S%.2f' % abs(coord['lat']))
    else: 
        lat_str = ('N%.2f' % abs(coord['lat']))
    if coord['lon']<0:
        lon_str = ('E%.2f' % abs(coord['lon']))
    else: 
        lon_str = ('W%.2f' % abs(coord['lon']))

    table_name = "_".join(('lat_%s_lon_%s_%s' % (lat_str,lon_str,units)).split('.'))
    return table_name