6 October 2025   6:09:40.618 PM
 
fd2d_predator_prey
  Fortran90 version
  A two dimensional finite difference algorithm
  for a predator-prey system.
 
  Enter parameter alpha:
  Enter parameter beta:
  Enter parameter gamma:
  Enter parameter delta:
  Enter a in [a,b]:
  Enter b in [a,b]:
  Enter space-step h:
  Enter maximum time t:
  Enter time-step Delta t:
  Enter SOLVE ( 0 = GMRES, 1 = Jacobi ):
 
  Parameters:
 
    ALPHA =        0.400000    
    BETA =          2.00000    
    GAMMA =        0.600000    
    DELTA =         10.0000    
 
    A =             0.00000    
    B =             500.000    
    H =             1.00000    
    BIGJ =          500
    (number of intervals on one side)
    DIMJ =          501
    (number of nodes on one side)
    N =                251001
    (total number of nodes)
 
    T =             150.000    
    (final time)
    DELT =         0.416667E-01
    (time step)
    TIME_STEPS =         3600
 
    MU =           0.416667E-01
    SOLVE =        0.416667E-01
          = Jacobi iteration.
 
  Arrays allocated.
 
  Arrays initialized.
 
FD2D_PREDATOR_PREY:
  Maximum number of nonzeros =      1255991
 
  Sparse matrix values assigned.
  
  Begin sorting.
 6 October 2025   6:09:40.668 PM
 6 October 2025   6:09:41.537 PM
 
  Sorting done.
 
  Compress the matrix data.
  Initial number of matrix entries, NZ_NUM =      1255991
  After compression,                NZ_NUM =      1253997
 
  Begin time loop.
   TIME_STEP =          360
 6 October 2025   6:10:10.125 PM
 
  Number of iterations:       4
  Last change in solution   0.584790E-05
 
  Number of iterations:      10
  Last change in solution   0.178352E-04
   TIME_STEP =          720
 6 October 2025   6:10:39.534 PM
 
  Number of iterations:       5
  Last change in solution   0.188241E-05
 
  Number of iterations:      10
  Last change in solution   0.267525E-04
   TIME_STEP =         1080
 6 October 2025   6:11:09.487 PM
 
  Number of iterations:       4
  Last change in solution   0.880453E-05
 
  Number of iterations:      10
  Last change in solution   0.380718E-04
   TIME_STEP =         1440
 6 October 2025   6:11:40.131 PM
 
  Number of iterations:       5
  Last change in solution   0.307342E-05
 
  Number of iterations:      10
  Last change in solution   0.649733E-04
   TIME_STEP =         1800
 6 October 2025   6:12:11.416 PM
 
  Number of iterations:       5
  Last change in solution   0.433260E-05
 
  Number of iterations:      10
  Last change in solution   0.942496E-04
   TIME_STEP =         2160
 6 October 2025   6:12:42.697 PM
 
  Number of iterations:       5
  Last change in solution   0.436230E-05
 
  Number of iterations:      10
  Last change in solution   0.102442E-03
   TIME_STEP =         2520
 6 October 2025   6:13:13.963 PM
 
  Number of iterations:       5
  Last change in solution   0.592924E-05
 
  Number of iterations:      10
  Last change in solution   0.127553E-03
   TIME_STEP =         2880
 6 October 2025   6:13:45.254 PM
 
  Number of iterations:       5
  Last change in solution   0.529609E-05
 
  Number of iterations:      10
  Last change in solution   0.132707E-03
   TIME_STEP =         3240
 6 October 2025   6:14:16.555 PM
 
  Number of iterations:       5
  Last change in solution   0.653224E-05
 
  Number of iterations:      10
  Last change in solution   0.124188E-03
   TIME_STEP =         3600
 6 October 2025   6:14:47.840 PM
 
  Number of iterations:       5
  Last change in solution   0.456149E-05
 
  Number of iterations:      10
  Last change in solution   0.126209E-03
 
FD2D_PREDATOR_PREY:
  Normal end of execution.
 
 6 October 2025   6:14:48.041 PM