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*  Research Computing Services                            *;
*  Introduction to SAS                                    *;
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*  SAS Means procedure                                    *;
*                                                         *;
*  1. Execute the code as is and explore the output       *;
*     for each mean procedure                             *;
*  2. Modify the condition to filter the data and         *;
*     examine the output                                  *;
*                                                         *;
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* Read more:                                               ;
*    means:  https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/proc/p0f0fjpjeuco4gn1ri963f683mi4.htm  *;
*            https://www.sas.com/content/dam/SAS/en_ca/User%20Group%20Presentations/Vancouver-User-Group/JasonShurgold-ProcMeans-Nov2014.pdf *;



/* Include sas program that sets input library */
%include "setup.sas";


/* brief summaries for numeric columns */
proc means data=mydata.med_visits;
    title "Summaries for Age, Height, DBP and SBP variables";
        var Age Height DBP SBP;
run;


/* brief summaries for numeric columns */
proc means data=mydata.med_visits;
    title "Summaries for Age, Height, DBP and SBP variables";
        var Age Height DBP SBP;
run;


/* use class to group by a categorical variable */
proc means data=mydata.med_visits;
    title "Summaries for SBP and DBP variables grouped by Sex";
        var DBP SBP;
        class Sex;
run;



/* use where to filter observations */
proc means data=mydata.med_visits;
    title "Summaries for SBP and DBP variables grouped by Sex for Age > 50";
        var DBP SBP;
        class Sex;
        where Age > 50;
run;


/* use by to split output into 2 separate tables - this requires that the data is sorted by this variable first*/
proc sort data=mydata.med_visits;
        by Sex;
run;
proc means data=mydata.med_visits;
    title "Summaries for SBP and DBP variables split Sex";
        var DBP SBP;
        by Sex;
run;