gzjb 发表于 2010-2-26 03:59
/**************************************************************************************************
****   Here Just show a complicated way to implement it. If anyone knows a simple way *****
*** Please let me know.  Thanks a lot                                      **********************************/;

***********************  SAS Code **********************;

DATA test;
input Week $ Day Price;
CARDS;
111 1 1
111 1 2
112 1 3
112 1 4
111 2 5
111 2 6
112 2 7
112 2 8
;


proc sort data=test;
by day  week;
run;


proc means data=test;
  by Day Week;
  var price;
  output out=meanout(keep= Week Day priceMean) MEAN(price)=priceMean;
run;


data _NULL_;
set meanout;
File 'C:\ProjStudy\gzjb\interchange.txt';
put Day Week PriceMean;
run;


data meanP;
  infile 'C:\ProjStudy\gzjb\interchange.txt';
  input Day Week1$ PriceMean1@;
  input Day Week2$ PriceMean2;
  run;



  data meanP1 (drop=tmPrice);
    set meanP;
        tmPrice=PriceMean1;
        PriceMean1=PriceMean2;
    PriceMean2=tmPrice;
        run;

        data meanPweek1(keep=Day Week1 PriceMean1)
        meanPweek2(keep=Day Week2 PriceMean2);
          set MeanP1;
        run;

        data mergePweek;
            merge meanPweek1(rename=( Week1=Week PriceMean1=MeanP)) meanPweek2(rename=( Week2=Week PriceMean2=MeanP));
            by Day Week;
    run;

data lastData;
  merge test mergePweek;
  by Day Week;
  run;

proc print noobs; run;

******************************************
SAS Output:
****************************************
                              
                                Week    Day    Price      MeanP

                                    111      1       1       3.5
                                    111      1       2       3.5
                                    112      1       3       1.5
                                    112      1       4       1.5
                                    111      2       5       7.5
                                    111      2       6       7.5
                                    112      2       7       5.5
                                    112      2       8       5.5

zenith1107 发表于 2010-2-26 00:07
在下是 SAS  新手，请多指教。

DATA test;
input Week $ Day Price;
CARDS;
111 1 1
111 1 2
112 1 3
112 1 4
111 2 5
111 2 6
112 2 7
112 2 8
;

I want to create a new variable MEANP that stores the mean PRICE for the observations in the same DAY but different WEEK. For example, for the 1st and 2nd row, the value of MEANP both = the mean PRICE of the rows where WEEK=112 and DAY=1 (the 3rd and 4th rows) and for the 3rd and 4th row, MEANP both = the mean PRICE of the rows where WEEK=111 and DAY=1 (the 1st and 2nd rows). And the final result would look like this:

WEEK DAY PRICE MEANP
111 1 1 3.5
111 1 2 3.5
112 1 3 1.5
112 1 4 1.5
111 2 5 7.5
111 2 6 7.5
112 2 7 5.5
112 2 8 5.5

I'm wondering if there's an easy way to do that. Any help is greatly appreciated.

Thanks!

bobguy 发表于 2010-2-26 07:35
It can be much simplified as,

DATA test;