用matlab实现拟合的几个例子源码，
％x,y应是原始数据，下面的数据仅是为了说明问题而自设的示例数据。-Matlab fitting used to achieve a few examples of source code, x, y should be the raw data, the following data only to illustrate the problem of sample-based data.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002266s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.092543s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002284s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.002187s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002235s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003760s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.002128s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003350s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014580s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.002432s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 4871 [ RunTime:0.001325s ]
