def set_boundary_conditions_access(g_a):
# this will reset the outer (ghost) elements back to the boundary cond.
if rlo == 0 or clo == 0 or chi == dim:
a = ga.access_ghosts(g_a)
if rlo == 0:
a[0,:] = 100 # I own a top row
if clo == 0:
a[:,0] = 75 # I own a left column
if chi == dim:
a[:,-1] = 50 # I own a right column
ga.release_update_ghosts(g_a)
ga.sync()
ga.release_update_ghosts(g_a)
ga.sync()
set_boundary_conditions_access(g_a)
iteration = 0
start = ga.wtime()
while True:
ga.sync()
iteration += 1
if iteration % HOW_MANY_STEPS_BEFORE_CONVERGENCE_TEST == 0:
# check for convergence will occur, so make a copy of the GA
ga.copy(g_a, g_b)
# the iteration
ga.update_ghosts(g_a)
set_boundary_conditions_access(g_a)
my_array = ga.access_ghosts(g_a)
my_array[1:-1,1:-1] = (
my_array[0:-2, 1:-1] +
my_array[2:, 1:-1] +
my_array[1:-1,0:-2] +
my_array[1:-1, 2:]) / 4
ga.release_ghosts(g_a)
if iteration % HOW_MANY_STEPS_BEFORE_CONVERGENCE_TEST == 0:
if convergence_test_L2(g_a, g_b):
break
if DEBUG or True and rank == 0:
print ga.get(g_a)
if rank == 0:
print iteration