Dipole Array (two element Array) Simulation in 4NEC2

Dear All,

I am trying to simulate dipole array in 4nec2, but i am not getting correct results for patterns.
e.g for two element array with lambda/4 spacing between them and 90 degree phase difference, I should get a cardiac shape pattern but I could not get. I have attached expected pattern along with simulation(plots & code). can any one guide me what is the problem. Apparently, there is no error.
Thank you in advance.Word..doc