Register to reply

Newton Raphson Method on Fortran90

by jhosamelly
Tags: fortran90, method, newton, raphson
Share this thread:
jhosamelly
#1
Dec2-12, 01:00 AM
P: 126
Here's what I need to do:

"Compare the effectiveness of the bisection method and Newton’s method for the
equation x^3−2x−2 = 0 which has a single root between x=−4 and x = 2."


So far I've done

ok. this is working but of course I need to do iteration which I don't know how. Can someone teach me please? I'm trying the Newton-Raphson Method first.

Thanks for the help in advance.


EDITED: Sorry, I posted the wrong pic earlier. Here's the correct one.
Phys.Org News Partner Science news on Phys.org
Sapphire talk enlivens guesswork over iPhone 6
Geneticists offer clues to better rice, tomato crops
UConn makes 3-D copies of antique instrument parts
gsal
#2
Dec2-12, 12:34 PM
P: 873
program nr
real:: x, xnew, err

write(*,*) "starting x?:"
read(*,*) x

do
    xnew = x - ( (x**3 - (2*x) - 2) / ( ( 3*(x**2) )-2) )
    err = 100*abs( (xnew-x)/x )
    x = xnew
    write(*,*) "x = ", xnew, "  error = ", err
    if (err < 0.000001) exit
end do

end program nr
jhosamelly
#3
Dec3-12, 06:36 AM
P: 126
thanks :))) Is that the iteration already?

gsal
#4
Dec3-12, 12:49 PM
P: 873
Newton Raphson Method on Fortran90

Yes.

Isn't it? Run it and verify the solution


Register to reply

Related Discussions
Newton-Raphson method Calculus & Beyond Homework 12
Newton–Raphson method - Finite difference method Differential Equations 5
Help with Newton-Raphson Method Engineering, Comp Sci, & Technology Homework 9
Newton-Raphson method Calculus & Beyond Homework 6
Newton-Raphson method for y=1/f(x) General Math 2