import torch
from torch import nn
from d2l import torch as d2l
batch_size, num_steps = 32, 35
train_iter, vocab = d2l.load_data_time_machine(batch_size, num_steps)
初始化模型参数
def get_params(vocab_size, num_hiddens, device):
num_inputs = num_outputs = vocab_size
def normal(shape):
return torch.randn(size=shape, device=device) * 0.01
def three():
return (normal(
(num_inputs, num_hiddens)), normal((num_hiddens, num_hiddens)),
torch.zeros(num_hiddens, device=device))
W_xz, W_hz, b_z = three()
W_xr, W_hr, b_r = three()
W_xh, W_hh, b_h = three()
W_hq = normal((num_hiddens, num_outputs))
b_q = torch.zeros(num_outputs, device=device)
params = [W_xz, W_hz, b_z, W_xr, W_hr, b_r, W_xh, W_hh, b_h, W_hq, b_q]
for param in params:
param.requires_grad_(True)
return params
定义隐藏状态的初始化函数
def init_gru_state(batch_size, num_hiddens, device):
return (torch.zeros((batch_size, num_hiddens), device=device),)
定义门控循环单元模型
def gru(inputs, state, params):
W_xz, W_hz, b_z, W_xr, W_hr, b_r, W_xh, W_hh, b_h, W_hq, b_q = params
H, = state
outputs = []
for X in inputs:
Z = torch.sigmoid((X @ W_xz) + (H @ W_hz) + b_z)
R = torch.sigmoid((X @ W_xr) + (H @ W_hr) + b_r)
H_tilda = torch.tanh((X @ W_xh) + ((R * H) @ W_hh) + b_h)
H = Z * H + (1 - Z) * H_tilda
Y = H @ W_hq + b_q
outputs.append(Y)
return torch.cat(outputs, dim=0), (H,)
训练
vocab_size, num_hiddens, device = len(vocab), 256, d2l.try_gpu()
num_epochs, lr = 500, 1
model = d2l.RNNModelScratch(len(vocab), num_hiddens, device, get_params,
init_gru_state, gru)
d2l.train_ch8(model, train_iter, vocab, lr, num_epochs, device)
perplexity 1.1, 24634.0 tokens/sec on cuda:0 time traveller for so it will be convenient to speak of himwas e travelleryou can show black is white by argument said filby
简洁实现
num_inputs = vocab_size
gru_layer = nn.GRU(num_inputs, num_hiddens)
model = d2l.RNNModel(gru_layer, len(vocab))
model = model.to(device)
d2l.train_ch8(model, train_iter, vocab, lr, num_epochs, device)
perplexity 1.0, 308866.0 tokens/sec on cuda:0 time travelleryou can show black is white by argument said filby travelleryou can show black is white by argument said filby