May  9 2025   9:25:16.869 PM
 
md():
  FORTRAN90 version
  A molecular dynamics program.
 
  Enter ND, the spatial dimension (2 or 3 ):
 
  Enter NP, the number of particles (500, for instance):
 
  Enter STEP_NUM, the number of time steps (500, for instance):
 
  ND, the spatial dimension, is        3
  NP, the number of particles in the simulation is     1000
  STEP_NUM, the number of time steps, is      400
  DT, the size of each time step, is   0.100000E-03
 
  Initializing positions, velocities, and accelerations.
 
  Computing initial forces and energies.
 
  At each step, we report the potential and kinetic energies.
  The sum of these energies should be a constant.
  As an accuracy check, we also print the relative error
  in the total energy.
 
      Step      Potential       Kinetic        (P+K-E0)/E0
                Energy P        Energy K       Relative Energy Error
 
         0     498090.         0.00000         0.00000    
        40     498090.        0.610465E-01    0.204253E-10
        80     498090.        0.253823        0.185788E-10
       120     498090.        0.578519        0.134468E-10
       160     498089.         1.03530        0.333418E-11
       200     498089.         1.62439       -0.134231E-10
       240     498088.         2.34610       -0.384941E-10
       280     498087.         3.20079       -0.735760E-10
       320     498086.         4.18888       -0.120379E-09
       360     498085.         5.31089       -0.180558E-09
       400     498084.         6.56737       -0.255856E-09
 
  Elapsed cpu time for main computation:
     18.3871     seconds
 
md():
  Normal end of execution.
 
May  9 2025   9:25:35.307 PM