PL/SQL :: Finding The Max Value

I have the following query where i need to find the max value[code]  with t as 

(   select 'L1' R_nm ,'Data' R_Data , 'Obj' R_Obj , 'Wd' r_prec , '2' val 
from dual   union all   select 'L1' , 'Data', 'Obj' , 'No', '4'
from dualunion all   select 'L2' , 'Data', 'Obj' , 'No', '4' from dual )  
select t.*, max(val) over(partition by r_nm,r_data,r_obj)  rk from t[/code] 

My expected output should be
[code]

r_nm    r_data     r_obj   r_prec   val     rkL1        Data         Obj     Wd       2       1L1        Data         Obj     No       4        2L2        Data         Obj     Yes      1       1

[/code]