How to sum sine waves up by using IP blocks

[Altera_Forum]

Hi, My task was to create two different freq. sine waves and sum them up. I defined them as signals but how to sum them by using IP clocks? Can some please help me? You can take a look to my code in attached vhd file. Thx in advance

[Altera_Forum]

Im not sure what the problem is - why cant you just have: 

 q <= sin1 + sin2  ?

[Altera_Forum]

it's giving error. It says "can't determine definition of operator ""+"" -- found 0 possible definitions

[Altera_Forum]

+ isn't defined for std_logic_vector. You have signed sine table, why not using signed variables?

[Altera_Forum]

Thank you very very much. I appreciate, it's done.