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The source code of Fixed Point Iteration method. Here the equation x3 - 2x - 5 = 0 is solved by the method of Fixed Point Iteration in FORTRAN language with CODE::BLOCKS.
The equation x3 - 2x - 5 = 0 is solved here by the method of Fixed Point Iteration in FORTRAN language with CODE::BLOCKS. Here the trick of algorithm of Fixed Point Iteration is given bellow:
1. Take a point enclosed to the solution.
2. Make another function which gives the value of x.
3. Put the point value in the new function and this will be the new point.
4. Do as before until you get the result.
The programming source code is given bellow:
program fixed
implicit none
real::f,x,g,x0,x1,tol
integer::i,itrtn
print*,"Enter the initial point:"
read(*,*)x0
print*,"Enter the total iteration:"
read(*,*)itrtn
print*,"Enter the tolerance:"
read(*,*)tol
print*,x0
do 10 i = 1,itrtn
x1 = g(x0);
print*,x1
if(f(x1).eq.0) then
print*, "The soln is:",x1
stop
end if
if(abs(x0-x1).le.tol) then
print*,"Approximate soln is:",x1
stop
end if
x0 = x1
10 continue
print*,"Maximum iteration failed"
end program
real function f(x)
real::x
f = x**3 - 2*x -5
return
end function
real function g(x)
real::x
g = (x+5.)**(1./3.)
return
end function