def test_learning_rate_update(self):
"""Check the learning rate update is applied to tile."""
loss_func = mse_loss
x_b = Tensor([[0.1, 0.2], [0.2, 0.4]])
y_b = Tensor([[0.3], [0.6]])
layer1 = self.get_layer(2, 3)
layer2 = self.get_layer(3, 1)
model = Sequential(layer1, layer2)
if self.use_cuda:
x_b = x_b.cuda()
y_b = y_b.cuda()
model = model.cuda()
opt = AnalogSGD(model.parameters(), lr=0.5)
opt.regroup_param_groups(model)
new_lr = 0.07
for param_group in opt.param_groups:
param_group['lr'] = new_lr
pred = model(x_b)
loss = loss_func(pred, y_b)
loss.backward()
opt.step()
self.assertAlmostEqual(layer1.analog_tile.get_learning_rate(), new_lr)
def train_model(model, loss_func, x_b, y_b):
"""Train the model."""
opt = AnalogSGD(model.parameters(), lr=0.1)
opt.regroup_param_groups(model)
epochs = 10
for _ in range(epochs):
pred = model(x_b)
loss = loss_func(pred, y_b)
loss.backward()
opt.step()
opt.zero_grad()
def get_model_and_x(self):
"""Trains a simple model."""
# Prepare the datasets (input and expected output).
x = Tensor([[0.1, 0.2, 0.4, 0.3], [0.2, 0.1, 0.1, 0.3]])
y = Tensor([[1.0, 0.5], [0.7, 0.3]])
# Define a single-layer network, using a constant step device type.
rpu_config = self.get_rpu_config()
rpu_config.forward.out_res = -1. # Turn off (output) ADC discretization.
rpu_config.forward.w_noise_type = OutputWeightNoiseType.ADDITIVE_CONSTANT
rpu_config.forward.w_noise = 0.02
rpu_config.noise_model = PCMLikeNoiseModel(g_max=25.0)
model = AnalogLinear(4, 2, bias=True, rpu_config=rpu_config)
# Move the model and tensors to cuda if it is available.
if self.use_cuda:
x = x.cuda()
y = y.cuda()
model.cuda()
# Define an analog-aware optimizer, preparing it for using the layers.
opt = AnalogSGD(model.parameters(), lr=0.1)
opt.regroup_param_groups(model)
for _ in range(100):
# Add the training Tensor to the model (input).
pred = model(x)
# Add the expected output Tensor.
loss = mse_loss(pred, y)
# Run training (backward propagation).
loss.backward()
opt.step()
return model, x
# Imports from aihwkit.
from aihwkit.nn import AnalogLinear
from aihwkit.optim.analog_sgd import AnalogSGD
from aihwkit.simulator.devices import ConstantStepResistiveDevice
# Prepare the datasets (input and expected output).
x_b = Tensor([[0.1, 0.2, 0.0, 0.0], [0.2, 0.4, 0.0, 0.0]])
y_b = Tensor([[0.3], [0.6]])
# Define a multiple-layer network, using a constant step device type.
model = Sequential(
AnalogLinear(4, 2, resistive_device=ConstantStepResistiveDevice()),
AnalogLinear(2, 2, resistive_device=ConstantStepResistiveDevice()),
AnalogLinear(2, 1, resistive_device=ConstantStepResistiveDevice()))
# Define an analog-aware optimizer, preparing it for using the layers.
opt = AnalogSGD(model.parameters(), lr=0.5)
opt.regroup_param_groups(model)
for epoch in range(100):
# Add the training Tensor to the model (input).
pred = model(x_b)
# Add the expected output Tensor.
loss = mse_loss(pred, y_b)
# Run training (backward propagation).
loss.backward()
opt.step()
print('Loss error: {:.16f}'.format(loss))