Conduct a t-test on data sorted by variables in SAS

In SAS, to conduct a t-test on data sorted by variables, use the BY statement in the TTEST procedure. The following example tests gender difference in weight in each area:

PROC SORT DATA=deer;
  BY area;
  
PROC TTEST;
  CLASS female;
  VAR weight;
  BY area;
RUN;

You must sort the data by the variable area before using the BY statement in PROC TTEST. The CLASS statement specifies a binary group variable, and the VAR statement indicates the variable(s) to be compared.