{$DS.}Function FFORMA3D12(L1,L2,D) X=L1/D Y=L2/D XX=sqrt(1+X^2) YY=sqrt(1+Y^2) FFORMA3D12=(1/(2*pi))*(((X/XX)*(arctan(Y/XX)*Convert(deg,rad)))+((Y/YY)*(arctan(X/YY)*Convert(deg,rad)))) End