c This is a program for calculating contact anglec from QCM frequency  changec Newton-Raphson Methodc Input constant C, frequency change f, and initial guess10      print *,'Delta f= ?'	Read (*,*)f      	print *,'# of drops='	read (*,*)n		print *,'C=?'	read (*,*)C	print *,'Initail guess of contact angle=?(degree)'	read (*,*)theta	x=cos(theta/180.*3.1415926)c	Interation100	fx1=f/C*(3.1415926)**(2./3.)*(2-3*x+x**3)**(2./3)	fx2=(3*2.*n)**(2./3)*(1-x*x)	fx=fx1-fx2	dfx1=2*f/C*(3.1415926)**(2/3.)*(2.-3*x+x*x*x)**(-1./3)*(x*x-1)	dfx2=(3*2.*n)**(2/3.)*2.*x	dfx=dfx1+dfx2	x1=x	x=x-fx/dfx        iter=iter+1        print *,iter,fxc	converge criteria	error=abs(x1-x)	if (error.gt.1e-6) goto 100c	Output of results	theta = acos (x)/3.1415926*180	write(*,*)theta	c	Determination of another run	print *,'Another run?(yes=1,no=0)'	read *,run	if (run.eq.1) goto 10	end