求助字符串匹配查找

求助各位老师一个问题：

1. %macro a;
   
2. %let a=  tt cc fdx d x e r t s d   ;
   
3. 
   
4. %let c=%sysfunc(tranwrd(&a,t, ));
   
5. %put &c;
   
6. 
   
7. %mend;%a;

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代码中，例如我想查找并替换 &a 中 ‘t’ 的值，但是无论用任何办法，SAS只能返回第一个tt的位置，请问有什么办法能全字匹配查找么？谢谢

更直接点说，我想把：

1. %let a=  tt cc fdx d x t c f    ;
   
2. %let b=t c f;

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在&a中出现的&b挖掉：

1. %let c=%???????(&a,&b);
   
2. %put >>&c<<;
   
3. >>tt cc fdx d x<<

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1. /* Please note that the leading and trailing
   
2. spaces in the macro variable defined by %let
   
3. statement will be removed; */
   
4. 
   
5. %macro aa;
   
6. %let a = tt cc fdx d x e r t s d ;
   
7. 
   
8. %let c=%sysfunc(indexw(&a,t));
   
9. %put &a;
   
10. %put &c;
    
11. 
    
12. %mend;%aa;
    
13. %aa;
    
14. 
    
15. %macro a;
    
16. %let a= tt cc fdx d x e r t s d ;
    
17. %let b = t s d;
    
18. %let c=%sysfunc(tranwrd(&a,&b, %str() ));
    
19. %put &c;
    
20. 
    
21. %mend;
    
22. %a;

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目前我用的是：%if "%upcase(%scan(&a,&i,%str( )))" eq "T"

请问有更直接的办法么？

yongyitian 发表于 2013-9-21 21:20

从15行开始才是正点！

yongyitian 发表于 2013-9-21 21:20

indexw function is the one I'm looking for, thank you.

By the way, do you know how can identify sevel cases like :

%let a= tt cc fdx d x e r t s d ;
%let b = t d s;

I'm sorry, I omit the same order with &b and &c.

Tigflanker 发表于 2013-9-21 22:08
indexw function is the one I'm looking for, thank you.

By the way, do you know how can identify ...

If there is more than one case, you can try %do loop
or %if .. %then
      %do;
        ...;
      %end;
    %else %then %do; ... %end;

yongyitian 发表于 2013-9-21 21:05

For example :

1. %macro a;
   
2. %let a= ttt cc fdx d x e r t s d ;
   
3. %let c=%sysfunc(tranwrd(&a,t,ABC));
   
4. %put &c;
   
5. %mend;%a;

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The result is : ABCABCABC cc fdx d x e r ABC s d
But not : ttt cc fdx d x e r ABC s d

So, If you have any idear to avoid this problem.

Thank you !!

Tigflanker 发表于 2013-9-21 22:22
For example :The result is : ABCABCABC cc fdx d x e r ABC s d
But not : ttt cc fdx d x e r ABC s  ...

The idea is to add a space before and after t,
               and a space before and after ABC,
whitch means to use ' ABC ' to replace ' t '.

学习学习~~

不错，学习了