executing a function in sql plus
As another answer already said, call select myfunc(:y) from dual; , but you might find declaring and setting a variable in sqlplus a little tricky:
sql> var y numbersql> begin 2 select 7 into :y from dual; 3 end; 4 /PL/SQL procedure successfully completed.sql> print :y Y---------- 7sql> select myfunc(:y) from dual;