WUT_Computer_Science/code/threads.py

73 lines
2.6 KiB
Python

import numpy as np
import threading
import multiprocessing
import gc
import time
import sys
from time_measurement import time_measurement_longest, longest_time_accumulator, tests_time
import linear_algebra_utils as linAlg
@time_measurement_longest(longest_time_accumulator)
def RichardsonThread(A, b, x, _x, omega, start, end):
for i in range(start, end):
sigma = np.dot(A[i, :], _x) - A[i, i] * _x[i]
x[i] = (1 - omega) * _x[i] + omega * (b[i] - sigma) / A[i, i]
def RichardsonMethodThreads(A, b, lambda_min, lambda_max, max_iterations, x0=None, tol=1e-5):
longest_time_accumulator.total_time = 0
longest_time_accumulator.start = sys.float_info.max
longest_time_accumulator.end = 0
gc.disable()
start_time = time.perf_counter()
n = len(b)
x0 = x0 if x0 is not None else [0.0] * len(b)
x = x0[:]
omega = 0.05#2 / (lambda_min + lambda_max)
num_threads = multiprocessing.cpu_count()
threads = []
chunk_size = n // num_threads
max_iterations = 1000
for _ in range(max_iterations):
_x = x[:]
for i in range(num_threads):
start = i * chunk_size # start jest indeksem w A. Wątki otrzymują kolejny punkt startowy będący wielokrotnością rozmiaru porcji na wątek
end = n if i == num_threads - 1 else (i + 1) * chunk_size
thread = threading.Thread(target=RichardsonThread, args=(A, b, x, _x, omega, start, end))
threads.append(thread)
thread.start()
for thread in threads:
thread.join()
# Ax = linAlg.SequentialLinearAlgebraUtils.matrix_vector_multiply(A, x)
# residual = linAlg.SequentialLinearAlgebraUtils.vector_vector_subtraction(b, Ax)
# if (linAlg.SequentialLinearAlgebraUtils.vector_norm(residual) < tol):
# break
end_time = time.perf_counter()
gc.enable()
total_time = end_time - start_time
sequential_time = total_time - longest_time_accumulator.total_time
print(f"Total: {total_time:.3e}s, Seq: {sequential_time:.3e}s, Parallel (threads): {longest_time_accumulator.total_time:.3e}s, Tests time: {tests_time.total_time:.3e}s")
return x, 0
# # Przykładowe dane wejściowe
# np.random.seed(0) # Ustalanie ziarna dla powtarzalności wyników
# A = np.random.rand(20, 20) + 20 * np.eye(20) # Macierz przekątniowa z losowymi elementami
# b = np.random.rand(20) # Wektor wyrazów wolnych
# omega = 0.2
# n_iterations = 1000
# # Rozwiązanie układu równań metodą Richardson'a
# x = RichardsonMethodThreads(A, b, 5, 5, n_iterations)
# print("Rozwiązanie: ", x)