求助：为什么每次用by语句都会出错？

shiyiming

请问为什么每次用by语句都会出错？程序及错误如下。谢谢！
140  proc print data=resdat.class;
141
142  by sex;
143
144  run;

[color=#FF0000:gtozyc3x]ERROR: [/color:gtozyc3x]Data set RESDAT.CLASS is not sorted in ascending sequence. The current by-group has Sex = M
       and the next by-group has Sex = F.

shiyiming

That is because you did not sort the data set by variable 'sex' before you use a "by sex;" statement in the print procedure.

try to use a sort procedure before print it .

proc sort data=resdat.class;
       by sex;
run;

proc print data=resdat.class;
       by sex;
run;

Then the program will execute successfully.

shiyiming

To pobel: 问题已解决，谢谢！