我有一个温度文件,有多年的温度记录,格式如下:2012-04-12,16:13:09,20.62012-04-12,17:13:09,20.92012-04-12,18:13:09,20.62007-05-12,19:13:09,5.42007-05-12,20:13:09,20.62007-05-12,20:13:09,20.62005-08-11,11:13:09,20.62005-08-11,11:13:09,17.52005-08-13,07:13:09,20.62006-04-13,01:13:09,20.6每年都有不同的数字,记录的时间,所以Pandas的日期时间索引都是不