i'm using the below program but i keep getting error.What is wrong with my progam? real x complex y real m1,H0,Ms,P1,P2,P3,w0,wm,wh complex w1,w2,o1,o2 integer i,n real pi n=4000000000 pi=4*atan(1.0) m1=4*pi*1e-7 H0=39.79e3 Ms=1400e3 P1=0.7*0.12 P2=0.3*0.12 P3=P1-P2 w0=m1*(1.76e11)*H0 wm=m1*(1.76e11)*Ms wh=w0-P3*wm im=cmplx(0,1) w1=wm/2+wh-im*0.06*2*pi*x w2=wm/2-wh-im*0.06*2*pi*x o1=x**2-x*(2*wh-(P3*wm)/2)-w1*w2+(wm/2)*(P1*w2+P2*w1) o2=x**2+x*(2*wh-(P3*wm)/2)-w1*w2+(wm/2)*(P1*w2+P2*w1) do i=0,n x=i y=1+wm*(P1*w1*((w2)**2-x**2))/(o1*o2) & +wm*(P2*w2*((w1)**2-x**2))/(o1*o2) & -wm*((wm/2)*((P1*w2+P2*w1)**2)))/(o1*o2) & +wm*((wm/2)*((P3*x)**2))/(o1*o2) write(10,*)x,y enddo return end