Spaces:
Running
Running
# Copyright 2021 AlQuraishi Laboratory | |
# Copyright 2021 DeepMind Technologies Limited | |
# | |
# Licensed under the Apache License, Version 2.0 (the "License"); | |
# you may not use this file except in compliance with the License. | |
# You may obtain a copy of the License at | |
# | |
# http://www.apache.org/licenses/LICENSE-2.0 | |
# | |
# Unless required by applicable law or agreed to in writing, software | |
# distributed under the License is distributed on an "AS IS" BASIS, | |
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
# See the License for the specific language governing permissions and | |
# limitations under the License. | |
from functools import partialmethod, partial | |
import math | |
from typing import Optional, List | |
import torch | |
import torch.nn as nn | |
from dockformer.model.primitives import Linear, LayerNorm, Attention | |
from dockformer.utils.tensor_utils import permute_final_dims | |
class TriangleAttention(nn.Module): | |
def __init__( | |
self, c_in, c_hidden, no_heads, starting=True, inf=1e9 | |
): | |
""" | |
Args: | |
c_in: | |
Input channel dimension | |
c_hidden: | |
Overall hidden channel dimension (not per-head) | |
no_heads: | |
Number of attention heads | |
""" | |
super(TriangleAttention, self).__init__() | |
self.c_in = c_in | |
self.c_hidden = c_hidden | |
self.no_heads = no_heads | |
self.starting = starting | |
self.inf = inf | |
self.layer_norm = LayerNorm(self.c_in) | |
self.linear = Linear(c_in, self.no_heads, bias=False, init="normal") | |
self.mha = Attention( | |
self.c_in, self.c_in, self.c_in, self.c_hidden, self.no_heads | |
) | |
def forward(self, | |
x: torch.Tensor, | |
mask: Optional[torch.Tensor] = None, | |
use_memory_efficient_kernel: bool = False, | |
use_lma: bool = False, | |
) -> torch.Tensor: | |
""" | |
Args: | |
x: | |
[*, I, J, C_in] input tensor (e.g. the pair representation) | |
Returns: | |
[*, I, J, C_in] output tensor | |
""" | |
if mask is None: | |
# [*, I, J] | |
mask = x.new_ones( | |
x.shape[:-1], | |
) | |
if(not self.starting): | |
x = x.transpose(-2, -3) | |
mask = mask.transpose(-1, -2) | |
# [*, I, J, C_in] | |
x = self.layer_norm(x) | |
# [*, I, 1, 1, J] | |
mask_bias = (self.inf * (mask - 1))[..., :, None, None, :] | |
# [*, H, I, J] | |
triangle_bias = permute_final_dims(self.linear(x), (2, 0, 1)) | |
# [*, 1, H, I, J] | |
triangle_bias = triangle_bias.unsqueeze(-4) | |
biases = [mask_bias, triangle_bias] | |
x = self.mha( | |
q_x=x, | |
kv_x=x, | |
biases=biases, | |
use_memory_efficient_kernel=use_memory_efficient_kernel, | |
use_lma=use_lma | |
) | |
if(not self.starting): | |
x = x.transpose(-2, -3) | |
return x | |