Al salam alikom
well Blooz, i really thank u for ur reply, it really helped me....
but when i used it matlab, it gives a warning that this polymonial is not the default and also it tells me that i can use gftable command for faster computations
>> gf(135,8,283)*gf(2,8,283)
Warning: PRIM_POLY must be a primitive polynomial.
> In gf.gf at 96
Warning: PRIM_POLY must be a primitive polynomial.
> In gf.gf at 96
Warning: Lookup tables not defined for this order 2^8 and
primitive polynomial 283. Arithmetic still works
correctly but multiplication, exponentiation, and
inversion of elements is faster with lookup tables.
Use gftable to create and save the lookup tables.
> In gf.gettables at 35
In gf.mtimes at 20
Warning: PRIM_POLY must be a primitive polynomial.
> In gf.gf at 96
In gf.mtimes at 25
ans = GF(2^8) array. Primitive polynomial = D^8+D^4+D^3+D+1 (283 decimal)
Array elements =
21
so how can i use it within writing m-files within a user defined function
thanks again for ur help, i really appreciate it
salam alikom