如何退出SAS宏循环

%return是直接终止宏了，而不是跳出循环。

%%mend ml(n,m,zb);
多了一个%。



data a;
        do i=1 to &n;
                x=uniform(0);
                fi=arcos(-1);
                y=sin(2*fi*x);
                output;
                keep y x fi i;
        end;


%do j=2 %to &m;

1. data a;
   
2. 
   
3. do i=0 to 9 by 1;
   
4. 
   
5. do x=i+0.995 to i+1.005 by 0.001;
   
6. 
   
7. output;
   
8. 
   
9. end;
   
10. 
    
11. end;
    
12. 
    
13. drop i;
    
14. 
    
15. run;
    
16. 
    
17. 
    
18. 
    
19. %MACRO TST(min_n,max_n,max_range);
    
20. 
    
21. %let cls=&min_n;
    
22. 
    
23. %let rc=1;
    
24. 
    
25. %do %while (%eval(&rc));
    
26. 
    
27. proc fastclus data=a MAXCLUSTERS=&cls out=b_&cls;run;quit;
    
28. 
    
29. proc means noprint data=b_&cls;
    
30. var x; by cluster;
    
31. output out=menx&cls range=rx;
    
32. 
    
33. quit;
    
34. 
    
35. proc sort data=menx&cls;by rx;run;quit;
    
36. data _null_;
    
37.         set menx&cls;by rx;
    
38.         if _N_=1 then do;
    
39.                 call symput("min_range_now",rx);
    
40.         end;
    
41. run;
    
42. 
    
43. 
    
44. %put NOW MIN_RANGE IS &min_range_now N_CLS IS &cls;
    
45. 
    
46. %if &min_range_now<=&max_range %then %do;
    
47. 
    
48. %let rc=0;
    
49. 
    
50. %end;
    
51. 
    
52. %else %do;
    
53. 
    
54. %let cls=%eval(&cls+1);
    
55. 
    
56. %if &cls>&max_n %then %let rc=0;
    
57. 
    
58. %end;
    
59. 
    
60. %end;
    
61. 
    
62. %MEND TST;
    
63. 
    
64. %TST(1,150,0.01);

复制代码

但愿可以

harlon1976 发表于 2010-2-16 20:15
9楼的同志的程序是不是应该可以理解为退出%do，等价地退出宏。我仿照这个理解，编写如下程序：
%macro ml(n,m,zb);
data a;
do i=1 to &n;
x=uniform(0);
fi=arcos(-1);
y=sin(2*fi*x);
output;
keep y x fi i;
end;
%do j=2 %to &m;
proc fastclus data=a out=Clust&j maxclusters=&j noprint;
var x;
proc sort out=flei&j;by cluster;
proc means noprint data=flei&j;
var x; by cluster;
output out=menx&j(keep=rx) range=rx;
proc means data=menx&j noprint;
var rx;
output out=big&j max=zuizhi;
data pb&j;
set  big&j ;
%if zuizhi le &zb %then %return;
%end;
%%mend ml(n,m,zb);
%ml(200,15,0.4);run;
但提交出现问题，问题就在%if 这里，不知高手是否给予修正呢？
谢谢。
上面程序是确定一个最好的分类数，使得各个类内的变量的极差最大值小于事先给定的值，此时退出循环，得到最终的分类结果。

You are confused with macro programming and data step programming/SAS programming. A macro needs to compile before executed. A macro is nothing but a text generator.  Based on a data step variable to determine if exit-timing a macro is not working. Here is a workable idea.

Write two macro
1) A macro check the value to determine if it is needed to call another macro. In your case it will be in a data step.
2) Calculating macro in your case will be a proc fastclus, ect.

HTH

10# harlon1976


Based on what I understand your pseudo-macro codes I modify as below.
%let n=200;
data a;
do i=1 to &n;
x=uniform(0);
fi=arcos(-1);
y=sin(2*fi*x);
output;
keep y x fi i;
end;
run;
%macro fast(a, j);
proc fastclus data=a out=Clust&j maxclusters=&j noprint;
var x;
run;
proc sort out=flei&j;by cluster;
run;
proc means noprint data=flei&j;
var x; by cluster;
output out=menx&j(keep=rx) range=rx;
run;
proc means data=menx&j noprint;
var rx;
output out=big&j max=zuizhi;
run;
%mend;
%macro ml(m,zb);
%let trigger=0;
%do j=2 %to &m;
%if &trigger=0 %then %fast(a,&j);
data _null_;
set big&j;
if zuizhi le &zb then call symputx('trigger',1);
stop;
run;
%put >>>>>>>loop number j=&j;
%if &trigger=1 %then %return;
%if &j=&m %then %return;
%end;
%%mend ml;

%ml(20,0.1);

%GOTO 语句可以实现 参考如下：

%LET VAR=%STR(A B C);

%MACRO TEST;

%DO I=1 %TO 3;
        %LET T=%SCAN(&VAR.,&I);
        %PUT &T.;
        %IF "&T."="B" %THEN %DO;
                %LET C="HOLLE WORLD";
                %GOTO QUIT;
        %END;
%END;

%QUIT:

%MEND;       
       
%TEST;