def ba_proc(rows, cols, chrom_seq, pnum, counter, permutations):
"""
BA Algorithm function for use in a multiprocessor process.
:param rows: number of rows on the board.
:param cols: number of columns on the board.
:param chrom_seq: pre-initialised chromosome.
:param pnum: number of processors.
:param permutations: permutations calculation flag.
:param counter: reference to counter object.
:return: n/a
"""
#
# Plot the domino grid solutions; saving to a each to a file.
#
print("Saving resultant board plots.")
# Retrieve the expected number of holes and dominoes
(holes, dominoes) = cmn.calc_solution_holes(rows, cols)
dplobj = dpl.CPlot(rows, cols, "BA", holes, dominoes)
dplobj.set_proc_num(pnum)
#
# Create the backtracking algorithm object with the specified board size.
#
baobj = CBacktracking(rows, cols, dplobj, counter, permutations)
# Display the backtracking algorithm's properties
if pnum == 0:
print(baobj) # Only print it the once.
# Now ready to solve the problem using the chromosome.
print(
"Executing the backtracking algorithm on processor[{}].".format(pnum))
baobj.runp(chrom_seq)
def main():
"""
Main function entry point to calculating all the solutions to the (8 x 10)
board, by using the solutions from lower dimensions. These being 2x slices
of (3 x 8) solutions, plus 1x slice of (4 x 8) solutions.
:param: n/a
:return: n/a
"""
#
# Check that the solution folders are present, no point continuing if
# they are not there.
#
ok_to_proceed = True
soln_folders = ["3x8__8_holes-8_dominoes", "4x8__10_holes-11_dominoes"]
for folder in soln_folders:
if not os.path.exists(os.path.join(cmn.BA_FOLDER, folder)):
print("Error: {} doesn't exist.".format(folder))
ok_to_proceed = False
else:
print("Found solution folder '{}'".format(folder))
if not ok_to_proceed:
print("Missing solution folder(s) so quitting.")
sys.exit(-1)
#
# Load all the solutions into memory for speed and ease of processing.
#
solns = {"3x8": [], "4x8": []}
for folder in soln_folders:
path_str = os.path.join(cmn.BA_FOLDER, folder)
for fname in os.listdir(path_str):
# Identify a solution file and load it.
if fname.endswith(".npy"):
board = np.load(os.path.join(path_str, fname))
if folder == "3x8__8_holes-8_dominoes":
solns["3x8"].append(board)
else:
solns["4x8"].append(board)
# Need 3x nested for loops representing each of the 3 slices.
# As the seed board solutions are different we need to execute the nested
# loop three times to get full coverage, as follows:
all_solns = []
# 1) slice1: 3x8, slice2: 3x8, slice3: 4x8
all_solns.extend(get_solns(solns["3x8"], solns["3x8"], solns["4x8"]))
# 2) slice1: 3x8, slice2: 4x8, slice3: 3x8
all_solns.extend(get_solns(solns["3x8"], solns["4x8"], solns["3x8"]))
# 3) slice1: 4x8, slice2: 3x8, slice3: 3x8
all_solns.extend(get_solns(solns["4x8"], solns["3x8"], solns["3x8"]))
# Plot the domino board solutions; saving to a each to a file.
# Note we need to pass in a numpy 2D array!
max_holes, min_dominoes = cmn.calc_solution_holes(8, 10)
dplobj = dpl.CPlot(8, 10, "pattern", max_holes, min_dominoes)
for result in all_solns:
dplobj.write_soln_to_file(result)
dplobj.classify_solns()
dplobj.plot_all()
def main(grid, algo):
"""
Main reclassification script.
:param grid: grid dimensions in rows and columns.
:param algo: algorithm to be reclassified.
:return: execution time
"""
rows = int(grid[0])
cols = int(grid[1])
# Calculate solution maximum number of holes.
(max_holes, max_dominoes) = cmn.calc_solution_holes(rows, cols)
#
# Instantiate the plotting object.
#
dplobj = dpl.CPlot(rows, cols, algo, max_holes, max_dominoes)
#
# Scan the results folder solutions and update the class members
#
print("Scanning the previous results.")
dplobj.load_soln_info()
# print(dplobj) # debug output
#
# Scan the results folder for image files and remove any it finds
#
print("Removing old image solution files.")
for fname in os.listdir(dplobj.path_str):
if fname.endswith(".png"):
os.remove(os.path.join(dplobj.path_str, fname))
#
# Parse the solution files; classify the solutions and plot them.
#
print("Re-classfying the results.")
dplobj.classify_solns()
print("Plotting all the results.")
dplobj.plot_all()
print("Found {} total solutions and {} fundamental solutions" \
.format(dplobj.total_all_solns, dplobj.total_fundamental))
#
# Update the test information file with the correct number of fundamental solutions.
#
fname = os.path.join(dplobj.path_str, cmn.RESULTS_FILE)
if os.path.exists(fname):
print("Updating the number of fundamental solutions in {}".format(fname))
# The file exists so read in the entire contents
with open(fname, "r") as fin:
contents = fin.read()
# Update the number of fundamental solutions
repl = "Fundamental solutions: {}".format(dplobj.total_fundamental)
# Had to use regex '(?!...) look behind so that regex it didn't consume
# the 'Fundamental solutions: ' string.
contents = re.sub(r"(Fundamental solutions:\s*[0-9]+)", repl, contents, re.IGNORECASE)
# Write the file back again.
with open(fname, "w") as fout:
fout.write(contents)
def main(grid, calc_permutations, timed_execution):
"""
Main Bracktracking Algorithm implementation.
:param grid: grid dimensions in rows and columns.
:param timed_execution: flag to time algorithm execution.
:return: execution time
"""
start = time.time() # Used to time script execution.
rows = int(grid[0])
cols = int(grid[1])
# Set the number of parallel processes we want to run.
# This is dependent on the number of processors available and the
# initialisation values available and the board dimensions.
num_processors = mp.cpu_count()
print("Number of processors available: {}".format(num_processors))
# Create the chromosome initialisation list.
if calc_permutations and num_processors >= 9 and rows > 4 and cols > 4:
num_processors = 9 # Only use 9 processors
# Note: when calculating the permutations we need ALL combinations!
chrom_init_seq = [[cmn.CELL_SPACE, cmn.CELL_HDOMINO],
[cmn.CELL_SPACE, cmn.CELL_VDOMINO],
[cmn.CELL_SPACE, cmn.CELL_SPACE],
[cmn.CELL_HDOMINO, cmn.CELL_SPACE],
[cmn.CELL_HDOMINO, cmn.CELL_HDOMINO],
[cmn.CELL_HDOMINO, cmn.CELL_VDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_SPACE],
[cmn.CELL_VDOMINO, cmn.CELL_HDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_VDOMINO]]
if not calc_permutations and num_processors >= 8 and rows > 4 and cols > 4:
num_processors = 8 # Only use 8 processors
chrom_init_seq = [[cmn.CELL_SPACE, cmn.CELL_HDOMINO],
[cmn.CELL_SPACE, cmn.CELL_VDOMINO],
[cmn.CELL_HDOMINO, cmn.CELL_SPACE],
[cmn.CELL_HDOMINO, cmn.CELL_HDOMINO],
[cmn.CELL_HDOMINO, cmn.CELL_VDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_SPACE],
[cmn.CELL_VDOMINO, cmn.CELL_HDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_VDOMINO]]
elif not calc_permutations and num_processors >= 6 and rows >= 4 and cols >= 4:
num_processors = 6 # Only use 6 processors
chrom_init_seq = [[cmn.CELL_SPACE, cmn.CELL_HDOMINO],
[cmn.CELL_SPACE,
cmn.CELL_VDOMINO], [cmn.CELL_HDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_SPACE],
[cmn.CELL_VDOMINO, cmn.CELL_HDOMINO],
[cmn.CELL_VDOMINO, cmn.CELL_VDOMINO]]
elif num_processors >= 3 and rows >= 3 and cols >= 3:
num_processors = 3 # Only use 3 processors
chrom_init_seq = [[cmn.CELL_SPACE], [cmn.CELL_HDOMINO],
[cmn.CELL_VDOMINO]]
else:
num_processors = 1 # Only use 1 processor
chrom_init_seq = []
# Initialise our permutations counter object.
counter = Counter(0)
# Setup the BA algorithm to run on num_processors value, if possible.
if num_processors == 1:
print("System not sufficient to run parallel processes.")
ba_proc(rows, cols, chrom_init_seq, 0, counter, calc_permutations)
else:
print("Running {} parallel processes.".format(num_processors))
# Seeding each BA object with all the different possible combinations
# for the first board squares.
procs = []
for i in range(num_processors):
proc = Process(target=ba_proc,
args=(rows, cols, chrom_init_seq[i], i, counter,
calc_permutations))
procs.append(proc)
proc.start()
# Block until all cores have finished.
for proc in procs:
proc.join()
execution_time = time.time() - start
#
# Now display the number of permutations found.
#
if calc_permutations:
msg = "\n\nNumber of permutations = {}\n".format(counter.value())
print(msg)
fname = "{}x{}-permutations.txt".format(rows, cols)
fname = os.path.join(cmn.PERMUTATIONS_FOLDER, fname)
with open(fname, "w") as fout:
fout.write(msg)
#
# Parse the solution files; classify the solutions and plot them.
#
else:
# Retrieve the expected number of holes and dominoes
(holes, dominoes) = cmn.calc_solution_holes(rows, cols)
dplobj = dpl.CPlot(rows, cols, "BA", holes, dominoes)
dplobj.load_soln_info()
dplobj.classify_solns()
dplobj.plot_all()
#
# Write the version information to the results folder.
# - Python and script version information is recorded.
# - this includes the execution time in seconds.
#
verstr = cmn.get_version_str(SCRIPTINFO)
if dplobj.get_total_solns():
time_1st = float(execution_time / dplobj.get_total_solns())
else:
# protect against divide by zero
time_1st = execution_time
dplobj.write_test_info(verstr, execution_time, time_1st)
# Display the time taken if requested.
if timed_execution:
print("Script execution time:", execution_time, "seconds")
# Return the execution time.
return execution_time
def main(grid, timed_execution):
"""
Main Genetic Algorithm implementation.
:param grid: the board dimensions in rows and columns.
:param timed_execution: flag to time algorithm execution.
:return: execution time and total number of solutions found.
"""
# Setup the GA configuration and show the user
rows = int(grid[0])
cols = int(grid[1])
print('Running {} with board ({} x {}):'.format(SCRIPTNAME, rows, cols))
#
# Calculate solution maximum number of holes.
#
(max_holes, max_dominoes) = cmn.calc_solution_holes(rows, cols)
print("Maximum number of holes for {} x {} board is {}.".format(
rows, cols, max_holes))
print("Maximum number of dominoes for {} x {} board is {}.".format(
rows, cols, max_dominoes))
# Determine the chromosome size 'csize' from the maximum number of rows and
# columns that are possible; plus add some padding.
csize = int(max_holes + max_dominoes + 4)
print("Chromosome size = {}".format(csize))
print(
"Generations={}, Population={}, Crossover Probability={}, Mutation Rate={}"
.format(GENERATIONS_MAX, POPULATION_SIZE, CX_PROBABILITY,
MUTATION_RATE))
# Initialise the DEAP structure and evaluation object
toolbox, pop, fits = init_DEAP_structures(csize, cols, rows, max_holes,
max_dominoes)
#
# Run the evolution:
# Stop if we find a solution or we reach the maximum number of generations.
#
# Variable keeping track of the number of generations
generation = 0
start = time.time() # Used to time script execution.
while max(fits) < 100 and generation < GENERATIONS_MAX:
# Display the header at the regular intervals.
if not generation % 50:
print("\n {:<10}{:<10}{:<8}{:<8}{:<8}{:<8}".format(
"Gen", "Eval", "Min", "Max", "Avg", "Std"))
print("-" * 60)
# A new generation
random.seed(time.time()) # MUST ENSURE RANDOM SEED EACH RUN
generation = generation + 1
# Select the next generation individuals
offspring = toolbox.select(pop, len(pop))
# Clone the selected individuals
offspring = list(map(toolbox.clone, offspring))
for mutant in offspring:
# mutate an individual with probability MUTATION_RATE
# range [0.0, 1.0)
if random.random() < MUTATION_RATE:
toolbox.mutate(mutant)
del mutant.fitness.values
# Evaluate the individuals with an invalid fitness
invalid_ind = [ind for ind in offspring if not ind.fitness.valid]
fitnesses = map(toolbox.evaluate, invalid_ind)
for ind, fit in zip(invalid_ind, fitnesses):
ind.fitness.values = fit
# The population is entirely replaced by the offspring
pop[:] = offspring
# Gather all the fitnesses in one list and print the stats
fits = [ind.fitness.values[0] for ind in pop]
# Calculate and print out the statistics
length = len(pop)
mean = sum(fits) / length
sum2 = sum(x * x for x in fits)
std = abs(sum2 / length - mean**2)**0.5
print(" {:<10}{:<10}{:<8.2f}{:<8.2f}{:<8.2f}{:<8.2f}".format(
generation, len(invalid_ind), min(fits), max(fits), mean, std))
# Had to add time.sleep() to get around a weird bug, where times less than
# 1 second are not recorded/recognised. Simple 1 second delay and then we
# have to subtract the 1 second to get the actual time.
time.sleep(1)
execution_time = time.time() - start - 1
total_solns = int(0)
best = tools.selBest(pop, 1)[0]
# print("Best individual is %s, %s" % (best, best.fitness.values)) # debug
# Let the user know the result.
if best.fitness.values[0] >= 100:
print("\nSolution(s) Found.")
print("Saving resultant board plots.")
dplobj = dpl.CPlot(rows, cols, "GA", max_holes, max_dominoes)
solns = []
# Find all the solutions in the population as there may be more than 1
for ind in pop:
if ind.fitness.values[0] == 100:
result = cmn.convert2board(ind, rows, cols)
# Only add if the solution is unique!
unique = True
for soln in solns:
if np.array_equal(soln, result):
unique = False
break
if unique:
# print("ind={}".format(ind)) # debug
solns.append(result)
# Plot the domino board solutions; saving to a each to a file.
# Note we need to pass in a numpy 2D array!
dplobj.write_soln_to_file(result)
dplobj.classify_solns()
dplobj.plot_all()
#
# Write the version information to the results folder.
# - Python and script version information is recorded.
# - this includes the execution time in seconds.
#
total_solns = len(solns)
verstr = cmn.get_version_str(SCRIPTINFO)
time1st = execution_time / total_solns
dplobj.write_test_info(verstr, execution_time, time1st)
else:
print("\nFailed to find a solution.")
# Display the time taken if requested.
if timed_execution:
print("Script execution time:", execution_time, "seconds")
# Return the execution time.
return execution_time, total_solns