import numpy
from time import perf_counter

nx = 1201
ny = 1201

# Solution and previous solution arrays
sol = numpy.zeros((nx,ny))
soln = sol.copy()

for j in range(0,ny-1):
  sol[0,j] = 10.0
  sol[nx-1,j] = 1.0
# end for

for i in range(0,nx-1):
  sol[i,0] = 0.0
  sol[i,ny-1] = 0.0
# end for

# Iterate
start_time = perf_counter()
for kloop in range(1,100):
  soln = sol.copy()

  for i in range(1,nx-1):
    for j in range (1,ny-1):
      sol[i,j] = 0.25 * (soln[i,j-1] + soln[i,j+1] + soln[i-1,j] + soln[i+1,j])
    # end j for loop
  # end i for loop
#end for
end_time = perf_counter()

print(' ')
print('Elapsed wall clock time = %g seconds.' % (end_time-start_time) )
print(' ')