import sys def f(x): return x**3+x-1 def secant(x0,x1,n): for i in range(n): if f(x1)-f(x0) == 0: return x1 x_temp = x1 - (f(x1)*(x1-x0)*1.0)/(f(x1)-f(x0)) x0 = x1 x1 = x_temp return x1 def main(argv): if (len(sys.argv) != 4): sys.exit('Usage: secant_method.py <x0> <x1> <n>') print 'The root is: ', print secant(float(sys.argv[1]),float(sys.argv[2]),int(sys.argv[3])) if __name__ == "__main__": main(sys.argv[1:])