def main():
'''
* :ref:`API in English <lif_fc_mnist.main-en>`
.. _lif_fc_mnist.main-cn:
:return: None
使用全连接-LIF-全连接-LIF的网络结构，进行MNIST识别。这个函数会初始化网络进行训练，并显示训练过程中在测试集的正确率。
* :ref:`中文API <lif_fc_mnist.main-cn>`
.. _lif_fc_mnist.main-en:
The network with FC-LIF-FC-LIF structure for classifying MNIST. This function initials the network, starts training
and shows accuracy on test dataset.
'''
device = input(
'输入运行的设备，例如“cpu”或“cuda:0”\n input device, e.g., "cpu" or "cuda:0": ')
dataset_dir = input(
'输入保存MNIST数据集的位置，例如“./”\n input root directory for saving MNIST dataset, e.g., "./": '
)
batch_size = int(
input('输入batch_size，例如“64”\n input batch_size, e.g., "64": '))
learning_rate = float(
input('输入学习率，例如“1e-3”\n input learning rate, e.g., "1e-3": '))
T = int(input('输入仿真时长，例如“100”\n input simulating steps, e.g., "100": '))
tau = float(
input(
'输入LIF神经元的时间常数tau，例如“100.0”\n input membrane time constant, tau, for LIF neurons, e.g., "100.0": '
))
train_epoch = int(
input(
'输入训练轮数，即遍历训练集的次数，例如“100”\n input training epochs, e.g., "100": '))
log_dir = input(
'输入保存tensorboard日志文件的位置，例如“./”\n input root directory for saving tensorboard logs, e.g., "./": '
)
writer = SummaryWriter(log_dir)
# 初始化数据加载器
train_dataset = torchvision.datasets.MNIST(
root=dataset_dir,
train=True,
transform=torchvision.transforms.ToTensor(),
download=True)
test_dataset = torchvision.datasets.MNIST(
root=dataset_dir,
train=False,
transform=torchvision.transforms.ToTensor(),
download=True)
train_data_loader = torch.utils.data.DataLoader(dataset=train_dataset,
batch_size=batch_size,
shuffle=True,
drop_last=True)
test_data_loader = torch.utils.data.DataLoader(dataset=test_dataset,
batch_size=batch_size,
shuffle=False,
drop_last=False)
# 定义并初始化网络
net = nn.Sequential(nn.Flatten(), nn.Linear(28 * 28, 10, bias=False),
neuron.LIFNode(tau=tau))
net = net.to(device)
# 使用Adam优化器
optimizer = torch.optim.Adam(net.parameters(), lr=learning_rate)
# 使用泊松编码器
encoder = encoding.PoissonEncoder()
train_times = 0
max_test_accuracy = 0
test_accs = []
train_accs = []
for epoch in range(train_epoch):
net.train()
for img, label in tqdm(train_data_loader):
img = img.to(device)
label = label.to(device)
label_one_hot = F.one_hot(label, 10).float()
optimizer.zero_grad()
# 运行T个时长，out_spikes_counter是shape=[batch_size, 10]的tensor
# 记录整个仿真时长内，输出层的10个神经元的脉冲发放次数
for t in range(T):
if t == 0:
out_spikes_counter = net(encoder(img).float())
else:
out_spikes_counter += net(encoder(img).float())
# out_spikes_counter / T 得到输出层10个神经元在仿真时长内的脉冲发放频率
out_spikes_counter_frequency = out_spikes_counter / T
# 损失函数为输出层神经元的脉冲发放频率，与真实类别的MSE
# 这样的损失函数会使，当类别i输入时，输出层中第i个神经元的脉冲发放频率趋近1，而其他神经元的脉冲发放频率趋近0
loss = F.mse_loss(out_spikes_counter_frequency, label_one_hot)
loss.backward()
optimizer.step()
# 优化一次参数后，需要重置网络的状态，因为SNN的神经元是有“记忆”的
functional.reset_net(net)
# 正确率的计算方法如下。认为输出层中脉冲发放频率最大的神经元的下标i是分类结果
accuracy = (out_spikes_counter_frequency.max(1)[1] == label.to(
device)).float().mean().item()
writer.add_scalar('train_accuracy', accuracy, train_times)
train_accs.append(accuracy)
train_times += 1
net.eval()
with torch.no_grad():
# 每遍历一次全部数据集，就在测试集上测试一次
test_sum = 0
correct_sum = 0
for img, label in test_data_loader:
img = img.to(device)
for t in range(T):
if t == 0:
out_spikes_counter = net(encoder(img).float())
else:
out_spikes_counter += net(encoder(img).float())
correct_sum += (out_spikes_counter.max(1)[1] == label.to(
device)).float().sum().item()
test_sum += label.numel()
functional.reset_net(net)
test_accuracy = correct_sum / test_sum
writer.add_scalar('test_accuracy', test_accuracy, epoch)
test_accs.append(test_accuracy)
max_test_accuracy = max(max_test_accuracy, test_accuracy)
print(
f'Epoch {epoch}: device={device}, dataset_dir={dataset_dir}, batch_size={batch_size}, learning_rate={learning_rate}, T={T}, log_dir={log_dir}, max_test_accuracy={max_test_accuracy}, train_times={train_times}'
)
# 保存绘图用数据
net.eval()
functional.set_monitor(net, True)
with torch.no_grad():
img, label = test_dataset[0]
img = img.to(device)
for t in range(T):
if t == 0:
out_spikes_counter = net(encoder(img).float())
else:
out_spikes_counter += net(encoder(img).float())
out_spikes_counter_frequency = (out_spikes_counter / T).cpu().numpy()
print(f'Firing rate: {out_spikes_counter_frequency}')
output_layer = net[-1] # 输出层
v_t_array = np.asarray(output_layer.monitor['v']).squeeze(
).T # v_t_array[i][j]表示神经元i在j时刻的电压值
np.save("v_t_array.npy", v_t_array)
s_t_array = np.asarray(output_layer.monitor['s']).squeeze(
).T # s_t_array[i][j]表示神经元i在j时刻释放的脉冲，为0或1
np.save("s_t_array.npy", s_t_array)
train_accs = np.array(train_accs)
np.save('train_accs.npy', train_accs)
test_accs = np.array(test_accs)
np.save('test_accs.npy', test_accs)
def play(use_cuda,
pt_path,
env_name,
hidden_size,
played_frames=60,
save_fig_num=0,
fig_dir=None,
figsize=(12, 6),
firing_rates_plot_type='bar',
heatmap_shape=None):
T = 16
plt.rcParams['figure.figsize'] = figsize
plt.ion()
env = gym.make(env_name).unwrapped
device = torch.device("cuda" if use_cuda else "cpu")
n_states = env.observation_space.shape[0]
n_actions = env.action_space.n
policy_net = DQSN(n_states, hidden_size, n_actions, T).to(device)
policy_net.load_state_dict(torch.load(pt_path, map_location=device))
env.reset()
state = torch.zeros([1, n_states], dtype=torch.float, device=device)
with torch.no_grad():
functional.set_monitor(policy_net, True)
delta_lim = 0
over_score = 1e9
for i in count():
LIF_v = policy_net(state) # shape=[1, 2]
action = LIF_v.max(1)[1].view(1, 1).item()
if firing_rates_plot_type == 'bar':
plt.subplot2grid((2, 9), (1, 0), colspan=3)
elif firing_rates_plot_type == 'heatmap':
plt.subplot2grid((2, 3), (1, 0))
plt.xticks(np.arange(2), ('Left', 'Right'))
plt.ylabel('Voltage')
plt.title('Voltage of LIF neurons at last time step')
delta_lim = (LIF_v.max() - LIF_v.min()) * 0.5
plt.ylim(LIF_v.min() - delta_lim, LIF_v.max() + delta_lim)
plt.yticks([])
plt.text(0,
LIF_v[0][0],
str(round(LIF_v[0][0].item(), 2)),
ha='center')
plt.text(1,
LIF_v[0][1],
str(round(LIF_v[0][1].item(), 2)),
ha='center')
plt.bar(np.arange(2),
LIF_v.squeeze(),
color=['r', 'gray'] if action == 0 else ['gray', 'r'],
width=0.5)
if LIF_v.min() - delta_lim < 0:
plt.axhline(0, color='black', linewidth=0.1)
IF_spikes = np.asarray(
policy_net.fc[1].monitor['s']) # shape=[16, 1, 256]
firing_rates = IF_spikes.mean(axis=0).squeeze()
if firing_rates_plot_type == 'bar':
plt.subplot2grid((2, 9), (0, 4), rowspan=2, colspan=5)
elif firing_rates_plot_type == 'heatmap':
plt.subplot2grid((2, 3), (0, 1), rowspan=2, colspan=2)
plt.title('Firing rates of IF neurons')
if firing_rates_plot_type == 'bar':
# 绘制柱状图
plt.xlabel('Neuron index')
plt.ylabel('Firing rate')
plt.xlim(0, firing_rates.size)
plt.ylim(0, 1.01)
plt.bar(np.arange(firing_rates.size), firing_rates, width=0.5)
elif firing_rates_plot_type == 'heatmap':
# 绘制热力图
heatmap = plt.imshow(firing_rates.reshape(heatmap_shape),
vmin=0,
vmax=1,
cmap='ocean')
plt.gca().invert_yaxis()
cbar = heatmap.figure.colorbar(heatmap)
cbar.ax.set_ylabel('Magnitude', rotation=90, va='top')
functional.reset_net(policy_net)
subtitle = f'Position={state[0][0].item(): .2f}, Velocity={state[0][1].item(): .2f}, Pole Angle={state[0][2].item(): .2f}, Pole Velocity At Tip={state[0][3].item(): .2f}, Score={i}'
state, reward, done, _ = env.step(action)
if done:
over_score = min(over_score, i)
subtitle = f'Game over, Score={over_score}'
plt.suptitle(subtitle)
state = torch.from_numpy(state).float().to(device).unsqueeze(0)
screen = env.render(mode='rgb_array').copy()
screen[300, :, :] = 0 # 画出黑线
if firing_rates_plot_type == 'bar':
plt.subplot2grid((2, 9), (0, 0), colspan=3)
elif firing_rates_plot_type == 'heatmap':
plt.subplot2grid((2, 3), (0, 0))
plt.xticks([])
plt.yticks([])
plt.title('Game screen')
plt.imshow(screen, interpolation='bicubic')
plt.pause(0.001)
if i < save_fig_num:
plt.savefig(os.path.join(fig_dir, f'{i}.png'))
if done and i >= played_frames:
env.close()
plt.close()
break
'''
train(use_cuda=False, model_dir='./model/CartPole-v0/state', log_dir='./log', env_name='CartPole-v0', \
hidden_size=256, num_episodes=500, seed=1)
'''
play(use_cuda=False, pt_path='./model/CartPole-v0/policy_net_256_max.pt', env_name='CartPole-v0', \
hidden_size=256, played_frames=300)
# Omitting pruning for all BN layers
BN_list = ['static_conv.1', 'conv.2', 'conv.5', 'conv.9', 'conv.12', 'conv.15']
for name, param in net.named_parameters():
if any(BN_name in name for BN_name in BN_list):
bn_params += [param]
ttl_cnt += param.numel()
else:
weight_params += [param]
w_cnt += param.numel()
ttl_cnt += param.numel()
###### TEST MODE ######
if test:
with torch.no_grad():
# Turn on monitor
set_monitor(net, True)
# Record total spike times by layer
spike_times = dict()
for name, module in net.named_modules():
if hasattr(module, 'monitor'):
spike_times[name] = 0
test_sum = 0
correct_sum = 0
for img, label in test_data_loader:
img = img.cuda(non_blocking=True)
label = label.cuda(non_blocking=True)
