HELP!! radiation pattern of a vibrating plate

hi, i wanted to plot radiation pattern of a vibrating plate by numerical integration of Rayeigh's formula. here i am keeping r=some constant, theta=0:pi/30:pi,phi=0:pi/30:2*pi and wanted to plot P=dblquad(@(x,y) (1i*w*p/(2*pi))*(sin(pi*x/l).*sin(pi*y/l).*exp(-1i*k*sqrt((.5-r*cos(theta).*cos(phi)).^2+(.5-r*cos(theta).*sin(phi)).^2+(r.*sin(theta)).^2))./sqrt((.5-r*cos(theta).*cos(phi)).^2+(.5-r*cos(theta).*sin(phi)).^2+(r.*sin(theta)).^2)),0,1,0,1);

Pressure=abs(P);

on a hemispherical surface. PLEASE HELP ME!!