I'm sorry for not being specific. I meant it doesn't converge for all roots, e.g. cube root.
On Jan 15, 10:18 pm, Dave <dave_and_da...@juno.com> wrote: > @Gene: Actually, Newton's Method for sqrt(a), where a > 0, also > sometimes called Heron's Method, converges for every initial guess x_0> 0. > This is not true generally for Newton's Method, but it is true > > for Newton's Method applied to f(x) = x^2 - a. > > Dave > > On Jan 15, 5:39 pm, Gene <gene.ress...@gmail.com> wrote: > > > > > To find sqrt(a), this is equivalent to Newton's Method with f(x)=x^2 - > > a. Newton is: x_{i+1} = x_i + f'(x_i) / f'(x_i). So you have x_{i+1} > > = x_i + (x_i^2 - a) / (2 x_i) = (x + a/x) / 2, which is just what the > > Babylonian method says to do. > > > Newton's method roughly doubles the number of significant bits in the > > answer with every iteration _when it converges_. The problem is that > > it doesn't converge to every root. There's a huge literature on this, > > which I'll let you find yourself. > > > On Jan 15, 10:22 pm, Ankur Garg <ankurga...@gmail.com> wrote: > > > > Hello > > > > I was going through this link > > > >http://www.geeksforgeeks.org/archives/3187 > > > > Wonder what is the time complexity for this..?Can anyone explain > > > > > Regards > > > Ankur -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.