當數據丟失時SAS轉置

Question

我有一個數據集，其中包含大量在不同時間點完成的實驗室測試。我試圖將數據集從長變換到寬變，但問題在於實驗室測試根據測試類型發生在不同的時間點。當我調換它時，我失去了判斷結果來自哪個時間點的能力。看到我的示例代碼如下：

*Create test data; 
data long; 
do subject=1 to 10; 
    do test=1 to 3; 
     do visit=1 to 3; 
      result=rand("Uniform"); 
     output; 
end; end; end; 
run; 

*Now remove records at certain visits depending upon the test type; 
data long; set long; 
    if test=2 and visit=2 then delete; 
    if test=3 and visit=1 then delete; 
run; 

*Sort and transpose; 
*Test 2 should only be at visit 1 and 3, and test 3 at visits 2 and 3; 
*This transpose does not accomplish that goal; 
proc sort data=long; by subject test visit;run; 
proc transpose data=long out=wide; 
    by subject test ; 
    var result; 
run; 

Answer 1

對於您的示例數據，您只需將一個ID語句添加到您的PROC TRANSPOSE代碼。這樣它將使用VISIT的值來命名結果列。您可能還想將PREFIX =選項添加到PROC TRANSPOSE語句。

proc transpose data=long out=wide prefix=visit; 
    by subject test ; 
    id visit ; 
    var result; 
run;