Tag: first last

SAS: Concatenate Values in Multiple Rows by Group

For example, data table contains student grades  for the term. Each grade is one record and the term, program, student id information are the same  for the student.  The following data step can be used to order the data table and then concatenate the grade records into something like ‘A/A/B/B+/A’ for each student.

proc sort data= one;
by groupvar1 groupvar2 groupvar3;
run;
data two;
set one;
by groupvar1 groupvar2 groupvar3;
firstgroup = first.groupvar2;
lastgroup = last.groupvar2;
retain catvar;
if firstgroup =1 then catvar=trim(targetvar);
else catvar=catx('/',catvar, targetvar);
if lastgroup ne 1 then delete;
keep groupvar1 groupvar2 catvar;
run;

SAS: Identify first and last record by group

Staff are in two wage category “H” and “S” . Sort the table by wage category and wage rate.  Firstrate will equal to 1 if it is the first record in the wagecategory, and the lastrate will equal to 1 if it is the last record in the wagecategory.

proc sort data=sasuser.staff out =sortstaff;
by wagecategory wagerate;
run;
data sortstaff;
set sortstaff;
by wagecategory;
firstrate = first.wagecategory;
lastrate = last.wagecategory;
run;