Files
ligandmpnn/sc_utils.py

1159 lines
36 KiB
Python

import sys
import numpy as np
import torch
import torch.distributions as D
import torch.nn as nn
from model_utils import (
DecLayer,
DecLayerJ,
EncLayer,
PositionalEncodings,
cat_neighbors_nodes,
gather_edges,
gather_nodes,
)
from openfold.data.data_transforms import atom37_to_torsion_angles, make_atom14_masks
from openfold.np.residue_constants import (
restype_atom14_mask,
restype_atom14_rigid_group_positions,
restype_atom14_to_rigid_group,
restype_rigid_group_default_frame,
)
from openfold.utils import feats
from openfold.utils.rigid_utils import Rigid
torch_pi = torch.tensor(np.pi, device="cpu")
map_mpnn_to_af2_seq = torch.tensor(
[
[1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
],
device="cpu",
)
def pack_side_chains(
feature_dict,
model_sc,
num_denoising_steps,
num_samples=10,
repack_everything=True,
num_context_atoms=16,
):
device = feature_dict["X"].device
torsion_dict = make_torsion_features(feature_dict, repack_everything)
feature_dict["X"] = torsion_dict["xyz14_noised"]
feature_dict["X_m"] = torsion_dict["xyz14_m"]
if "Y" not in list(feature_dict):
feature_dict["Y"] = torch.zeros(
[
feature_dict["X"].shape[0],
feature_dict["X"].shape[1],
num_context_atoms,
3,
],
device=device,
)
feature_dict["Y_t"] = torch.zeros(
[feature_dict["X"].shape[0], feature_dict["X"].shape[1], num_context_atoms],
device=device,
)
feature_dict["Y_m"] = torch.zeros(
[feature_dict["X"].shape[0], feature_dict["X"].shape[1], num_context_atoms],
device=device,
)
h_V, h_E, E_idx = model_sc.encode(feature_dict)
feature_dict["h_V"] = h_V
feature_dict["h_E"] = h_E
feature_dict["E_idx"] = E_idx
for step in range(num_denoising_steps):
mean, concentration, mix_logits = model_sc.decode(feature_dict)
mix = D.Categorical(logits=mix_logits)
comp = D.VonMises(mean, concentration)
pred_dist = D.MixtureSameFamily(mix, comp)
predicted_samples = pred_dist.sample([num_samples])
log_probs_of_samples = pred_dist.log_prob(predicted_samples)
sample = torch.gather(
predicted_samples, dim=0, index=torch.argmax(log_probs_of_samples, 0)[None,]
)[0,]
torsions_pred_unit = torch.cat(
[torch.sin(sample[:, :, :, None]), torch.cos(sample[:, :, :, None])], -1
)
torsion_dict["torsions_noised"][:, :, 3:] = torsions_pred_unit * torsion_dict[
"mask_fix_sc"
] + torsion_dict["torsions_true"] * (1 - torsion_dict["mask_fix_sc"])
pred_frames = feats.torsion_angles_to_frames(
torsion_dict["rigids"],
torsion_dict["torsions_noised"],
torsion_dict["aatype"],
torch.tensor(restype_rigid_group_default_frame, device=device),
)
xyz14_noised = feats.frames_and_literature_positions_to_atom14_pos(
pred_frames,
torsion_dict["aatype"],
torch.tensor(restype_rigid_group_default_frame, device=device),
torch.tensor(restype_atom14_to_rigid_group, device=device),
torch.tensor(restype_atom14_mask, device=device),
torch.tensor(restype_atom14_rigid_group_positions, device=device),
)
xyz14_noised = xyz14_noised * feature_dict["X_m"][:, :, :, None]
feature_dict["X"] = xyz14_noised
S_af2 = torsion_dict["S_af2"]
feature_dict["X"] = xyz14_noised
log_prob = pred_dist.log_prob(sample) * torsion_dict["mask_fix_sc"][
..., 0
] + 2.0 * (1 - torsion_dict["mask_fix_sc"][..., 0])
tmp_types = torch.tensor(restype_atom14_to_rigid_group, device=device)[S_af2]
tmp_types[tmp_types < 4] = 4
tmp_types -= 4
atom_types_for_b_factor = torch.nn.functional.one_hot(tmp_types, 4) # [B, L, 14, 4]
uncertainty = log_prob[:, :, None, :] * atom_types_for_b_factor # [B,L,14,4]
b_factor_pred = uncertainty.sum(-1) # [B, L, 14]
feature_dict["b_factors"] = b_factor_pred
feature_dict["mean"] = mean
feature_dict["concentration"] = concentration
feature_dict["mix_logits"] = mix_logits
feature_dict["log_prob"] = log_prob
feature_dict["sample"] = sample
feature_dict["true_torsion_sin_cos"] = torsion_dict["torsions_true"]
return feature_dict
def make_torsion_features(feature_dict, repack_everything=True):
device = feature_dict["mask"].device
mask = feature_dict["mask"]
B, L = mask.shape
xyz37 = torch.zeros([B, L, 37, 3], device=device, dtype=torch.float32)
xyz37[:, :, :3] = feature_dict["X"][:, :, :3]
xyz37[:, :, 4] = feature_dict["X"][:, :, 3]
S_af2 = torch.argmax(
torch.nn.functional.one_hot(feature_dict["S"], 21).float()
@ map_mpnn_to_af2_seq.to(device).float(),
-1,
)
masks14_37 = make_atom14_masks({"aatype": S_af2})
temp_dict = {
"aatype": S_af2,
"all_atom_positions": xyz37,
"all_atom_mask": masks14_37["atom37_atom_exists"],
}
torsion_dict = atom37_to_torsion_angles("")(temp_dict)
rigids = Rigid.make_transform_from_reference(
n_xyz=xyz37[:, :, 0, :],
ca_xyz=xyz37[:, :, 1, :],
c_xyz=xyz37[:, :, 2, :],
eps=1e-9,
)
if not repack_everything:
xyz37_true = feature_dict["xyz_37"]
temp_dict_true = {
"aatype": S_af2,
"all_atom_positions": xyz37_true,
"all_atom_mask": masks14_37["atom37_atom_exists"],
}
torsion_dict_true = atom37_to_torsion_angles("")(temp_dict_true)
torsions_true = torch.clone(torsion_dict_true["torsion_angles_sin_cos"])[
:, :, 3:
]
mask_fix_sc = feature_dict["chain_mask"][:, :, None, None]
else:
torsions_true = torch.zeros([B, L, 4, 2], device=device)
mask_fix_sc = torch.ones([B, L, 1, 1], device=device)
random_angle = (
2 * torch_pi * torch.rand([S_af2.shape[0], S_af2.shape[1], 4], device=device)
)
random_sin_cos = torch.cat(
[torch.sin(random_angle)[..., None], torch.cos(random_angle)[..., None]], -1
)
torsions_noised = torch.clone(torsion_dict["torsion_angles_sin_cos"])
torsions_noised[:, :, 3:] = random_sin_cos * mask_fix_sc + torsions_true * (
1 - mask_fix_sc
)
pred_frames = feats.torsion_angles_to_frames(
rigids,
torsions_noised,
S_af2,
torch.tensor(restype_rigid_group_default_frame, device=device),
)
xyz14_noised = feats.frames_and_literature_positions_to_atom14_pos(
pred_frames,
S_af2,
torch.tensor(restype_rigid_group_default_frame, device=device),
torch.tensor(restype_atom14_to_rigid_group, device=device).long(),
torch.tensor(restype_atom14_mask, device=device),
torch.tensor(restype_atom14_rigid_group_positions, device=device),
)
xyz14_m = masks14_37["atom14_atom_exists"] * mask[:, :, None]
xyz14_noised = xyz14_noised * xyz14_m[:, :, :, None]
torsion_dict["xyz14_m"] = xyz14_m
torsion_dict["xyz14_noised"] = xyz14_noised
torsion_dict["mask_for_loss"] = mask
torsion_dict["rigids"] = rigids
torsion_dict["torsions_noised"] = torsions_noised
torsion_dict["mask_fix_sc"] = mask_fix_sc
torsion_dict["torsions_true"] = torsions_true
torsion_dict["S_af2"] = S_af2
return torsion_dict
class Packer(nn.Module):
def __init__(
self,
edge_features=128,
node_features=128,
num_positional_embeddings=16,
num_chain_embeddings=16,
num_rbf=16,
top_k=30,
augment_eps=0.0,
atom37_order=False,
device=None,
atom_context_num=16,
lower_bound=0.0,
upper_bound=20.0,
hidden_dim=128,
num_encoder_layers=3,
num_decoder_layers=3,
dropout=0.1,
num_mix=3,
):
super(Packer, self).__init__()
self.edge_features = edge_features
self.node_features = node_features
self.num_positional_embeddings = num_positional_embeddings
self.num_chain_embeddings = num_chain_embeddings
self.num_rbf = num_rbf
self.top_k = top_k
self.augment_eps = augment_eps
self.atom37_order = atom37_order
self.device = device
self.atom_context_num = atom_context_num
self.lower_bound = lower_bound
self.upper_bound = upper_bound
self.hidden_dim = hidden_dim
self.num_encoder_layers = num_encoder_layers
self.num_decoder_layers = num_decoder_layers
self.dropout = dropout
self.softplus = nn.Softplus(beta=1, threshold=20)
self.features = ProteinFeatures(
edge_features=edge_features,
node_features=node_features,
num_positional_embeddings=num_positional_embeddings,
num_chain_embeddings=num_chain_embeddings,
num_rbf=num_rbf,
top_k=top_k,
augment_eps=augment_eps,
atom37_order=atom37_order,
device=device,
atom_context_num=atom_context_num,
lower_bound=lower_bound,
upper_bound=upper_bound,
)
self.W_e = nn.Linear(edge_features, hidden_dim, bias=True)
self.W_v = nn.Linear(node_features, hidden_dim, bias=True)
self.W_f = nn.Linear(edge_features, hidden_dim, bias=True)
self.W_v_sc = nn.Linear(node_features, hidden_dim, bias=True)
self.linear_down = nn.Linear(2 * hidden_dim, hidden_dim, bias=True)
self.W_torsions = nn.Linear(hidden_dim, 4 * 3 * num_mix, bias=True)
self.num_mix = num_mix
self.dropout = nn.Dropout(dropout)
# Encoder layers
self.encoder_layers = nn.ModuleList(
[
EncLayer(hidden_dim, hidden_dim * 2, dropout=dropout)
for _ in range(num_encoder_layers)
]
)
self.W_c = nn.Linear(hidden_dim, hidden_dim, bias=True)
self.W_e_context = nn.Linear(hidden_dim, hidden_dim, bias=True)
self.W_nodes_y = nn.Linear(hidden_dim, hidden_dim, bias=True)
self.W_edges_y = nn.Linear(hidden_dim, hidden_dim, bias=True)
self.context_encoder_layers = nn.ModuleList(
[DecLayer(hidden_dim, hidden_dim * 2, dropout=dropout) for _ in range(2)]
)
self.V_C = nn.Linear(hidden_dim, hidden_dim, bias=False)
self.V_C_norm = nn.LayerNorm(hidden_dim)
self.y_context_encoder_layers = nn.ModuleList(
[DecLayerJ(hidden_dim, hidden_dim, dropout=dropout) for _ in range(2)]
)
self.h_V_C_dropout = nn.Dropout(dropout)
# Decoder layers
self.decoder_layers = nn.ModuleList(
[
DecLayer(hidden_dim, hidden_dim * 3, dropout=dropout)
for _ in range(num_decoder_layers)
]
)
for p in self.parameters():
if p.dim() > 1:
nn.init.xavier_uniform_(p)
def encode(self, feature_dict):
mask = feature_dict["mask"]
V, E, E_idx, Y_nodes, Y_edges, E_context, Y_m = self.features.features_encode(
feature_dict
)
h_E_context = self.W_e_context(E_context)
h_V = self.W_v(V)
h_E = self.W_e(E)
mask_attend = gather_nodes(mask.unsqueeze(-1), E_idx).squeeze(-1)
mask_attend = mask.unsqueeze(-1) * mask_attend
for layer in self.encoder_layers:
h_V, h_E = layer(h_V, h_E, E_idx, mask, mask_attend)
h_V_C = self.W_c(h_V)
Y_m_edges = Y_m[:, :, :, None] * Y_m[:, :, None, :]
Y_nodes = self.W_nodes_y(Y_nodes)
Y_edges = self.W_edges_y(Y_edges)
for i in range(len(self.context_encoder_layers)):
Y_nodes = self.y_context_encoder_layers[i](Y_nodes, Y_edges, Y_m, Y_m_edges)
h_E_context_cat = torch.cat([h_E_context, Y_nodes], -1)
h_V_C = self.context_encoder_layers[i](h_V_C, h_E_context_cat, mask, Y_m)
h_V_C = self.V_C(h_V_C)
h_V = h_V + self.V_C_norm(self.h_V_C_dropout(h_V_C))
return h_V, h_E, E_idx
def decode(self, feature_dict):
h_V = feature_dict["h_V"]
h_E = feature_dict["h_E"]
E_idx = feature_dict["E_idx"]
mask = feature_dict["mask"]
device = h_V.device
V, F = self.features.features_decode(feature_dict)
h_F = self.W_f(F)
h_EF = torch.cat([h_E, h_F], -1)
h_V_sc = self.W_v_sc(V)
h_V_combined = torch.cat([h_V, h_V_sc], -1)
h_V = self.linear_down(h_V_combined)
for layer in self.decoder_layers:
h_EV = cat_neighbors_nodes(h_V, h_EF, E_idx)
h_V = layer(h_V, h_EV, mask)
torsions = self.W_torsions(h_V)
torsions = torsions.reshape(h_V.shape[0], h_V.shape[1], 4, self.num_mix, 3)
mean = torsions[:, :, :, :, 0].float()
concentration = 0.1 + self.softplus(torsions[:, :, :, :, 1]).float()
mix_logits = torsions[:, :, :, :, 2].float()
return mean, concentration, mix_logits
class ProteinFeatures(nn.Module):
def __init__(
self,
edge_features=128,
node_features=128,
num_positional_embeddings=16,
num_chain_embeddings=16,
num_rbf=16,
top_k=30,
augment_eps=0.0,
atom37_order=False,
device=None,
atom_context_num=16,
lower_bound=0.0,
upper_bound=20.0,
):
"""Extract protein features"""
super(ProteinFeatures, self).__init__()
self.edge_features = edge_features
self.node_features = node_features
self.num_positional_embeddings = num_positional_embeddings
self.num_chain_embeddings = num_chain_embeddings
self.num_rbf = num_rbf
self.top_k = top_k
self.augment_eps = augment_eps
self.atom37_order = atom37_order
self.device = device
self.atom_context_num = atom_context_num
self.lower_bound = lower_bound
self.upper_bound = upper_bound
# deal with oxygen index
# ------
self.N_idx = 0
self.CA_idx = 1
self.C_idx = 2
if atom37_order:
self.O_idx = 4
else:
self.O_idx = 3
# -------
self.positional_embeddings = PositionalEncodings(num_positional_embeddings)
# Features for the encoder
enc_node_in = 21 # alphabet for the sequence
enc_edge_in = (
num_positional_embeddings + num_rbf * 25
) # positional + distance features
self.enc_node_in = enc_node_in
self.enc_edge_in = enc_edge_in
self.enc_edge_embedding = nn.Linear(enc_edge_in, edge_features, bias=False)
self.enc_norm_edges = nn.LayerNorm(edge_features)
self.enc_node_embedding = nn.Linear(enc_node_in, node_features, bias=False)
self.enc_norm_nodes = nn.LayerNorm(node_features)
# Features for the decoder
dec_node_in = 14 * atom_context_num * num_rbf
dec_edge_in = num_rbf * 14 * 14 + 42
self.dec_node_in = dec_node_in
self.dec_edge_in = dec_edge_in
self.W_XY_project_down1 = nn.Linear(num_rbf + 120, num_rbf, bias=True)
self.dec_edge_embedding1 = nn.Linear(dec_edge_in, edge_features, bias=False)
self.dec_norm_edges1 = nn.LayerNorm(edge_features)
self.dec_node_embedding1 = nn.Linear(dec_node_in, node_features, bias=False)
self.dec_norm_nodes1 = nn.LayerNorm(node_features)
self.node_project_down = nn.Linear(
5 * num_rbf + 64 + 4, node_features, bias=True
)
self.norm_nodes = nn.LayerNorm(node_features)
self.type_linear = nn.Linear(147, 64)
self.y_nodes = nn.Linear(147, node_features, bias=False)
self.y_edges = nn.Linear(num_rbf, node_features, bias=False)
self.norm_y_edges = nn.LayerNorm(node_features)
self.norm_y_nodes = nn.LayerNorm(node_features)
self.periodic_table_features = torch.tensor(
[
[
0,
1,
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],
],
dtype=torch.long,
device=device,
)
def _dist(self, X, mask, eps=1e-6):
mask_2D = torch.unsqueeze(mask, 1) * torch.unsqueeze(mask, 2)
dX = torch.unsqueeze(X, 1) - torch.unsqueeze(X, 2)
D = mask_2D * torch.sqrt(torch.sum(dX**2, 3) + eps)
D_max, _ = torch.max(D, -1, keepdim=True)
D_adjust = D + (1.0 - mask_2D) * D_max
sampled_top_k = self.top_k
D_neighbors, E_idx = torch.topk(
D_adjust, np.minimum(self.top_k, X.shape[1]), dim=-1, largest=False
)
return D_neighbors, E_idx
def _make_angle_features(self, A, B, C, Y):
v1 = A - B
v2 = C - B
e1 = torch.nn.functional.normalize(v1, dim=-1)
e1_v2_dot = torch.einsum("bli, bli -> bl", e1, v2)[..., None]
u2 = v2 - e1 * e1_v2_dot
e2 = torch.nn.functional.normalize(u2, dim=-1)
e3 = torch.cross(e1, e2, dim=-1)
R_residue = torch.cat(
(e1[:, :, :, None], e2[:, :, :, None], e3[:, :, :, None]), dim=-1
)
local_vectors = torch.einsum(
"blqp, blyq -> blyp", R_residue, Y - B[:, :, None, :]
)
rxy = torch.sqrt(local_vectors[..., 0] ** 2 + local_vectors[..., 1] ** 2 + 1e-8)
f1 = local_vectors[..., 0] / rxy
f2 = local_vectors[..., 1] / rxy
rxyz = torch.norm(local_vectors, dim=-1) + 1e-8
f3 = rxy / rxyz
f4 = local_vectors[..., 2] / rxyz
f = torch.cat([f1[..., None], f2[..., None], f3[..., None], f4[..., None]], -1)
return f
def _rbf(
self,
D,
D_mu_shape=[1, 1, 1, -1],
lower_bound=0.0,
upper_bound=20.0,
num_bins=16,
):
device = D.device
D_min, D_max, D_count = lower_bound, upper_bound, num_bins
D_mu = torch.linspace(D_min, D_max, D_count, device=device)
D_mu = D_mu.view(D_mu_shape)
D_sigma = (D_max - D_min) / D_count
D_expand = torch.unsqueeze(D, -1)
RBF = torch.exp(-(((D_expand - D_mu) / D_sigma) ** 2))
return RBF
def _get_rbf(
self,
A,
B,
E_idx,
D_mu_shape=[1, 1, 1, -1],
lower_bound=2.0,
upper_bound=22.0,
num_bins=16,
):
D_A_B = torch.sqrt(
torch.sum((A[:, :, None, :] - B[:, None, :, :]) ** 2, -1) + 1e-6
) # [B, L, L]
D_A_B_neighbors = gather_edges(D_A_B[:, :, :, None], E_idx)[
:, :, :, 0
] # [B,L,K]
RBF_A_B = self._rbf(
D_A_B_neighbors,
D_mu_shape=D_mu_shape,
lower_bound=lower_bound,
upper_bound=upper_bound,
num_bins=num_bins,
)
return RBF_A_B
def features_encode(self, features):
"""
make protein graph and encode backbone
"""
S = features["S"]
X = features["X"]
Y = features["Y"]
Y_m = features["Y_m"]
Y_t = features["Y_t"]
mask = features["mask"]
R_idx = features["R_idx"]
chain_labels = features["chain_labels"]
if self.training and self.augment_eps > 0:
X = X + self.augment_eps * torch.randn_like(X)
Ca = X[:, :, self.CA_idx, :]
N = X[:, :, self.N_idx, :]
C = X[:, :, self.C_idx, :]
O = X[:, :, self.O_idx, :]
b = Ca - N
c = C - Ca
a = torch.cross(b, c, dim=-1)
Cb = -0.58273431 * a + 0.56802827 * b - 0.54067466 * c + Ca # shift from CA
_, E_idx = self._dist(Ca, mask)
backbone_coords_list = [N, Ca, C, O, Cb]
RBF_all = []
for atom_1 in backbone_coords_list:
for atom_2 in backbone_coords_list:
RBF_all.append(
self._get_rbf(
atom_1,
atom_2,
E_idx,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
)
RBF_all = torch.cat(tuple(RBF_all), dim=-1)
offset = R_idx[:, :, None] - R_idx[:, None, :]
offset = gather_edges(offset[:, :, :, None], E_idx)[:, :, :, 0] # [B, L, K]
d_chains = (
(chain_labels[:, :, None] - chain_labels[:, None, :]) == 0
).long() # find self vs non-self interaction
E_chains = gather_edges(d_chains[:, :, :, None], E_idx)[:, :, :, 0]
E_positional = self.positional_embeddings(offset.long(), E_chains)
E = torch.cat((E_positional, RBF_all), -1)
E = self.enc_edge_embedding(E)
E = self.enc_norm_edges(E)
V = torch.nn.functional.one_hot(S, self.enc_node_in).float()
V = self.enc_node_embedding(V)
V = self.enc_norm_nodes(V)
Y_t = Y_t.long()
Y_t_g = self.periodic_table_features[1][Y_t] # group; 19 categories including 0
Y_t_p = self.periodic_table_features[2][Y_t] # period; 8 categories including 0
Y_t_g_1hot_ = torch.nn.functional.one_hot(Y_t_g, 19) # [B, L, M, 19]
Y_t_p_1hot_ = torch.nn.functional.one_hot(Y_t_p, 8) # [B, L, M, 8]
Y_t_1hot_ = torch.nn.functional.one_hot(Y_t, 120) # [B, L, M, 120]
Y_t_1hot_ = torch.cat(
[Y_t_1hot_, Y_t_g_1hot_, Y_t_p_1hot_], -1
) # [B, L, M, 147]
Y_t_1hot = self.type_linear(Y_t_1hot_.float())
D_N_Y = torch.sqrt(
torch.sum((N[:, :, None, :] - Y) ** 2, -1) + 1e-6
) # [B, L, M, num_bins]
D_N_Y = self._rbf(
D_N_Y,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
D_Ca_Y = torch.sqrt(
torch.sum((Ca[:, :, None, :] - Y) ** 2, -1) + 1e-6
) # [B, L, M, num_bins]
D_Ca_Y = self._rbf(
D_Ca_Y,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
D_C_Y = torch.sqrt(
torch.sum((C[:, :, None, :] - Y) ** 2, -1) + 1e-6
) # [B, L, M, num_bins]
D_C_Y = self._rbf(
D_C_Y,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
D_O_Y = torch.sqrt(
torch.sum((O[:, :, None, :] - Y) ** 2, -1) + 1e-6
) # [B, L, M, num_bins]
D_O_Y = self._rbf(
D_O_Y,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
D_Cb_Y = torch.sqrt(
torch.sum((Cb[:, :, None, :] - Y) ** 2, -1) + 1e-6
) # [B, L, M, num_bins]
D_Cb_Y = self._rbf(
D_Cb_Y,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
f_angles = self._make_angle_features(N, Ca, C, Y)
D_all = torch.cat(
(D_N_Y, D_Ca_Y, D_C_Y, D_O_Y, D_Cb_Y, Y_t_1hot, f_angles), dim=-1
) # [B,L,M,5*num_bins+5]
E_context = self.node_project_down(D_all) # [B, L, M, node_features]
E_context = self.norm_nodes(E_context)
Y_edges = self._rbf(
torch.sqrt(
torch.sum((Y[:, :, :, None, :] - Y[:, :, None, :, :]) ** 2, -1) + 1e-6
)
) # [B, L, M, M, num_bins]
Y_edges = self.y_edges(Y_edges)
Y_nodes = self.y_nodes(Y_t_1hot_.float())
Y_edges = self.norm_y_edges(Y_edges)
Y_nodes = self.norm_y_nodes(Y_nodes)
return V, E, E_idx, Y_nodes, Y_edges, E_context, Y_m
def features_decode(self, features):
"""
Make features for decoding. Explicit side chain atom and other atom distances.
"""
S = features["S"]
X = features["X"]
X_m = features["X_m"]
mask = features["mask"]
E_idx = features["E_idx"]
Y = features["Y"][:, :, : self.atom_context_num]
Y_m = features["Y_m"][:, :, : self.atom_context_num]
Y_t = features["Y_t"][:, :, : self.atom_context_num]
X_m = X_m * mask[:, :, None]
device = S.device
B, L, _, _ = X.shape
RBF_sidechain = []
X_m_gathered = gather_nodes(X_m, E_idx) # [B, L, K, 14]
for i in range(14):
for j in range(14):
rbf_features = self._get_rbf(
X[:, :, i, :],
X[:, :, j, :],
E_idx,
D_mu_shape=[1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
)
rbf_features = (
rbf_features
* X_m[:, :, i, None, None]
* X_m_gathered[:, :, :, j, None]
)
RBF_sidechain.append(rbf_features)
D_XY = torch.sqrt(
torch.sum((X[:, :, :, None, :] - Y[:, :, None, :, :]) ** 2, -1) + 1e-6
) # [B, L, 14, atom_context_num]
XY_features = self._rbf(
D_XY,
D_mu_shape=[1, 1, 1, 1, -1],
lower_bound=self.lower_bound,
upper_bound=self.upper_bound,
num_bins=self.num_rbf,
) # [B, L, 14, atom_context_num, num_rbf]
XY_features = XY_features * X_m[:, :, :, None, None] * Y_m[:, :, None, :, None]
Y_t_1hot = torch.nn.functional.one_hot(
Y_t.long(), 120
).float() # [B, L, atom_context_num, 120]
XY_Y_t = torch.cat(
[XY_features, Y_t_1hot[:, :, None, :, :].repeat(1, 1, 14, 1, 1)], -1
) # [B, L, 14, atom_context_num, num_rbf+120]
XY_Y_t = self.W_XY_project_down1(
XY_Y_t
) # [B, L, 14, atom_context_num, num_rbf]
XY_features = XY_Y_t.view([B, L, -1])
V = self.dec_node_embedding1(XY_features)
V = self.dec_norm_nodes1(V)
S_1h = torch.nn.functional.one_hot(S, self.enc_node_in).float()
S_1h_gathered = gather_nodes(S_1h, E_idx) # [B, L, K, 21]
S_features = torch.cat(
[S_1h[:, :, None, :].repeat(1, 1, E_idx.shape[2], 1), S_1h_gathered], -1
) # [B, L, K, 42]
F = torch.cat(
tuple(RBF_sidechain), dim=-1
) # [B,L,atom_context_num,14*14*num_rbf]
F = torch.cat([F, S_features], -1)
F = self.dec_edge_embedding1(F)
F = self.dec_norm_edges1(F)
return V, F