Files
5039dcf6ea TFT fixes (#55)
* fixies for running tft

* fix test set configs

* added AgeFeature back to the pipeline

* fixing AgeFeature

* revert setups changes

Co-authored-by: alex sliz-nagy <alex.sliz.nagy@blackswan.com>
2021-06-08 13:23:22 +02:00

297 lines
8.8 KiB
Python

from typing import List, Optional, Tuple
import numpy as np
import torch
import torch.nn as nn
from pts.modules import FeatureEmbedder as BaseFeatureEmbedder
class FeatureProjector(nn.Module):
def __init__(
self,
feature_dims: List[int],
embedding_dims: List[int],
):
super().__init__()
self.__num_features = len(feature_dims)
if self.__num_features > 1:
self.feature_slices = (
feature_dims[0:1] + np.cumsum(feature_dims)[:-1].tolist()
)
else:
self.feature_slices = feature_dims
self.feature_dims = feature_dims
self._projector = nn.ModuleList(
[
nn.Linear(in_features=in_feature, out_features=out_features)
for in_feature, out_features in zip(self.feature_dims, embedding_dims)
]
)
def forward(self, features: torch.Tensor) -> List[torch.Tensor]:
if self.__num_features > 1:
real_feature_slices = torch.tensor_split(
features, self.feature_slices[1:], dim=-1
)
else:
real_feature_slices = [features]
return [
proj(real_feature_slice)
for proj, real_feature_slice in zip(self._projector, real_feature_slices)
]
class FeatureEmbedder(BaseFeatureEmbedder):
def forward(self, features: torch.Tensor) -> List[torch.Tensor]:
concat_features = super(FeatureEmbedder, self).forward(features=features)
if self.__num_features > 1:
features = torch.chunk(concat_features, self.__num_features, dim=-1)
else:
features = [concat_features]
return features
class GatedLinearUnit(nn.Module):
def __init__(self, dim: int = -1, nonlinear: bool = True):
super().__init__()
self.dim = dim
self.nonlinear = nonlinear
def forward(self, x: torch.Tensor) -> torch.Tensor:
val, gate = torch.chunk(x, 2, dim=self.dim)
if self.nonlinear:
val = torch.tanh(val)
return torch.sigmoid(gate) * val
class GatedResidualNetwork(nn.Module):
def __init__(
self,
d_hidden: int,
d_input: Optional[int] = None,
d_output: Optional[int] = None,
d_static: Optional[int] = None,
dropout: float = 0.0,
):
super().__init__()
d_input = d_input or d_hidden
d_static = d_static or 0
if d_output is None:
d_output = d_input
self.add_skip = False
else:
if d_output != d_input:
self.add_skip = True
self.skip_proj = nn.Linear(in_features=d_input, out_features=d_output)
else:
self.add_skip = False
self.mlp = nn.Sequential(
nn.Linear(in_features=d_input + d_static, out_features=d_hidden),
nn.ELU(),
nn.Linear(in_features=d_hidden, out_features=d_hidden),
nn.Dropout(p=dropout),
nn.Linear(in_features=d_hidden, out_features=d_output * 2),
GatedLinearUnit(nonlinear=False),
)
self.lnorm = nn.LayerNorm(d_output)
def forward(
self, x: torch.Tensor, c: Optional[torch.Tensor] = None
) -> torch.Tensor:
if self.add_skip:
skip = self.skip_proj(x)
else:
skip = x
if c is not None:
x = torch.cat((x, c), dim=-1)
x = self.mlp(x)
x = self.lnorm(x + skip)
return x
class VariableSelectionNetwork(nn.Module):
def __init__(
self,
d_hidden: int,
n_vars: int,
dropout: float = 0.0,
add_static: bool = False,
):
super().__init__()
self.weight_network = GatedResidualNetwork(
d_hidden=d_hidden,
d_input=d_hidden * n_vars,
d_output=n_vars,
d_static=d_hidden if add_static else None,
dropout=dropout,
)
self.variable_network = nn.ModuleList(
[
GatedResidualNetwork(d_hidden=d_hidden, dropout=dropout)
for _ in range(n_vars)
]
)
def forward(
self, variables: List[torch.Tensor], static: Optional[torch.Tensor] = None
) -> Tuple[torch.Tensor, torch.Tensor]:
flatten = torch.cat(variables, dim=-1)
if static is not None:
static = static.expand_as(variables[0])
weight = self.weight_network(flatten, static)
weight = torch.softmax(weight.unsqueeze(-2), dim=-1)
var_encodings = [net(var) for var, net in zip(variables, self.variable_network)]
var_encodings = torch.stack(var_encodings, dim=-1)
var_encodings = torch.sum(var_encodings * weight, dim=-1)
return var_encodings, weight
class TemporalFusionEncoder(nn.Module):
def __init__(
self,
d_input: int,
d_hidden: int,
):
super().__init__()
self.encoder_lstm = nn.LSTM(
input_size=d_input, hidden_size=d_hidden, batch_first=True
)
self.decoder_lstm = nn.LSTM(
input_size=d_input, hidden_size=d_hidden, batch_first=True
)
self.gate = nn.Sequential(
nn.Linear(in_features=d_hidden, out_features=d_hidden * 2),
GatedLinearUnit(nonlinear=False),
)
if d_input != d_hidden:
self.skip_proj = nn.Linear(in_features=d_input, out_features=d_hidden)
self.add_skip = True
else:
self.add_skip = False
self.lnorm = nn.LayerNorm(d_hidden)
def forward(
self,
ctx_input: torch.Tensor,
tgt_input: torch.Tensor,
states: List[torch.Tensor],
):
ctx_encodings, states = self.encoder_lstm(ctx_input, states)
tgt_encodings, _ = self.decoder_lstm(tgt_input, states)
encodings = torch.cat((ctx_encodings, tgt_encodings), dim=1)
skip = torch.cat((ctx_input, tgt_input), dim=1)
if self.add_skip:
skip = self.skip_proj(skip)
encodings = self.gate(encodings)
encodings = self.lnorm(skip + encodings)
return encodings
class TemporalFusionDecoder(nn.Module):
def __init__(
self,
context_length: int,
prediction_length: int,
d_hidden: int,
d_var: int,
n_head: int,
dropout: float = 0.0,
):
super().__init__()
self.context_length = context_length
self.prediction_length = prediction_length
self.enrich = GatedResidualNetwork(
d_hidden=d_hidden,
d_static=d_var,
dropout=dropout,
)
self.attention = nn.MultiheadAttention(
embed_dim=d_hidden, num_heads=n_head, dropout=dropout
)
self.att_net = nn.Sequential(
nn.Linear(in_features=d_hidden, out_features=d_hidden * 2),
GatedLinearUnit(nonlinear=False),
)
self.att_lnorm = nn.LayerNorm(d_hidden)
self.ff_net = nn.Sequential(
GatedResidualNetwork(d_hidden=d_hidden, dropout=dropout),
nn.Linear(in_features=d_hidden, out_features=d_hidden * 2),
GatedLinearUnit(nonlinear=False),
)
self.ff_lnorm = nn.LayerNorm(d_hidden)
self.register_buffer(
"attn_mask",
self._generate_subsequent_mask(
prediction_length, prediction_length + context_length
),
)
@staticmethod
def _generate_subsequent_mask(
target_length: int, source_length: int
) -> torch.Tensor:
mask = (torch.triu(torch.ones(source_length, target_length)) == 1).transpose(
0, 1
)
mask = (
mask.float()
.masked_fill(mask == 0, float("-inf"))
.masked_fill(mask == 1, float(0.0))
)
return mask
def forward(
self, x: torch.Tensor, static: torch.Tensor, mask: torch.Tensor
) -> torch.Tensor:
static = static.repeat((1, self.context_length + self.prediction_length, 1))
skip = x[:, self.context_length :, ...]
x = self.enrich(x, static)
mask_pad = torch.ones_like(mask)[:, 0:1, ...]
mask_pad = mask_pad.repeat((1, self.prediction_length))
key_padding_mask = torch.cat((mask, mask_pad), dim=1).bool()
query_key_value = x.permute(1, 0, 2)
attn_output, _ = self.attention(
query=query_key_value[-self.prediction_length :, ...],
key=query_key_value,
value=query_key_value,
# key_padding_mask=key_padding_mask, # does not work on GPU :-(
attn_mask=self.attn_mask,
)
att = self.att_net(attn_output.permute(1, 0, 2))
x = x[:, self.context_length :, ...]
x = self.att_lnorm(x + att)
x = self.ff_net(x)
x = self.ff_lnorm(x + skip)
return x