ROUND

 

!Program name: ROUND

real*4 x

real*8 y

x=1.234e04

y=4.321

print *, x, y, nint(x), idnint(y), anint(x), anint(y)

stop

end

Comentários

Postar um comentário

Postagens mais visitadas deste blog

DATA

  ! Name of the program: DATA !Examples of data Implicit none !maximum integer value Integer :: A Integer (kind=2) :: B      !it uses two bytes Integer (kind=4) :: C      !it uses four bytes Integer (kind=8) :: D      !it uses eight bytes print *, huge(A), kind(A)  !it shows 2147483647 print *, huge(B), kind (B)  !it shows 32767     2 Print *, huge(C)          !it shows 2147483647      4 Print *, huge(D), kind (D) ! it shows 9223372036854775807    8 stop end
Leia mais

HYDROGEN-RADIAL

!--------------------------------------------------------------- !Program name: HYDROGEN-RADIAL !Radial equation of the hydrogen-like atom !Objective: plot the radial wave function for each n,l pair ! The equation is atomic units !--------------------------------------------------------------- !The Coulomb potential energy equation is: ! V(r) = -2Z/r ! The ceentrifugal potential equation is: ! VL=l(l+1)/r^2 ! The energy is: ! E=-2*Z/n^2 !--------------------------------------------------------------- ! Use of Numerov method to find the wave function ! Function fn from Numerov equation is ! Fn = 1 + K2*h^2/12 , where K2=-2(Veff - E) ! In the code, h is changed into dr !---------------------------------------------------------------   Program hydrogen   Implicit none   integer :: mesh, n, l, i, j, zeta, m, maxiter=100   Real*8 rmin, dr, zmesh, y_out_m   double precision :: e, fh12, norm, eps=1.0E-6    double precision, allocatable :: r(:), r2
Leia mais

HYDROGEN-POTENTIAL

  !--------------------------------------------------------------- !Program name: HYDROGEN-POTENTIAL !Objective: plot the effective potential energy as a function of radial distance !--------------------------------------------------------------- !The Coulomb potential energy equation is: ! V(r) = -KZq 2 /r = -(Kq 2 )(Z/r) ! K(Coulomb constant)= 9*10 9 Nm 2 C -2 ! q = - 1.602 x 10 -19 C ! Kq 2 =2.3 x 10 -28 ! The unit is Joule. We have to change into Rydberg. !---------------------------------------------------- ! The V(centrifugal) equation is: ! Vcent=6.1 x 10 -39 l(l+1)/r 2 (see text) ! The unit is Joule. We have to change into Rydberg !--------------------------------------------------------------- ! The unit of the radial distance, r, is meter. !---------------------------------------------------------------   Program hydrogen Implicit none   integer :: mesh, n, l, i, zeta   Real*8 rmin, dr, rmax   double precision :: oldr, e, kq2, h2m
Leia mais