Files
optical-regeneration/src/single-core-regen/util/complexNN.py
Joseph Hopfmüller 249fe1e940 wip
2025-01-27 21:05:49 +01:00

727 lines
23 KiB
Python

import torch
import torch.nn as nn
import torch.nn.functional as F
# from torchlambertw.special import lambertw
def complex_mse_loss(input, target, power=False, normalize=False, reduction="mean"):
"""
Compute the mean squared error between two complex tensors.
If power is set to True, the loss is computed as |input|^2 - |target|^2
"""
reduce = getattr(torch, reduction)
power_penalty = 0
if power:
input = (input * input.conj()).real.to(dtype=input.dtype.to_real())
target = (target * target.conj()).real.to(dtype=target.dtype.to_real())
if normalize:
power_penalty = ((input.max() - input.min()) - (target.max() - target.min())) ** 2
power_penalty += (input.min() - target.min()) ** 2
input = input - input.min()
input = input / input.max()
target = target - target.min()
target = target / target.max()
else:
if normalize:
power_penalty = (input.abs().max() - target.abs().max()) ** 2
input = input / input.abs().max()
target = target / target.abs().max()
if input.is_complex() and target.is_complex():
return reduce(torch.square(input.real - target.real) + torch.square(input.imag - target.imag)) + power_penalty
elif input.is_complex() or target.is_complex():
raise ValueError("Input and target must have the same type (real or complex)")
else:
return F.mse_loss(input, target, reduction=reduction) + power_penalty
def complex_sse_loss(input, target):
"""
Compute the sum squared error between two complex tensors.
"""
if input.is_complex():
return torch.sum(torch.square(input.real - target.real) + torch.square(input.imag - target.imag))
else:
return torch.sum(torch.square(input - target))
class UnitaryLayer(nn.Module):
def __init__(self, in_features, out_features, dtype=None):
assert in_features >= out_features
super(UnitaryLayer, self).__init__()
self.in_features = in_features
self.out_features = out_features
self.weight = nn.Parameter(torch.randn(in_features, out_features, dtype=dtype))
self.reset_parameters()
def reset_parameters(self):
q, _ = torch.linalg.qr(self.weight)
self.weight.data = q
def forward(self, x):
return torch.matmul(x, self.weight)
def __repr__(self):
return f"UnitaryLayer({self.in_features}, {self.out_features})"
class _Unitary(nn.Module):
def forward(self, X: torch.Tensor):
if X.ndim < 2:
raise ValueError(f"Only tensors with 2 or more dimensions are supported. Got a tensor of shape {X.shape}")
n, k = X.size(-2), X.size(-1)
transpose = n < k
if transpose:
X = X.transpose(-2, -1)
q, r = torch.linalg.qr(X)
# q: torch.Tensor = q
# r: torch.Tensor = r
d = r.diagonal(dim1=-2, dim2=-1).sgn()
q *= d.unsqueeze(-2)
if transpose:
q = q.transpose(-2, -1)
if n == k:
mask = (torch.linalg.det(q).abs() >= 0).to(q.dtype.to_real())
mask[mask == 0] = -1
mask = mask.unsqueeze(-1)
q[..., 0] *= mask
# X.copy_(q)
return q
def unitary(module: nn.Module, name: str = "weight") -> nn.Module:
weight = getattr(module, name, None)
if not isinstance(weight, torch.Tensor):
raise ValueError(f"Module '{module}' has no parameter or buffer '{name}'")
if weight.ndim < 2:
raise ValueError(f"Expected a matrix or batch of matrices. Got a tensor of {weight.ndim} dimensions.")
if weight.shape[-2] != weight.shape[-1]:
raise ValueError(f"Expected a square matrix or batch of square matrices. Got a tensor of shape {weight.shape}")
unit = _Unitary()
nn.utils.parametrize.register_parametrization(module, name, unit)
return module
class _SpecialUnitary(nn.Module):
def __init__(self):
super().__init__()
def forward(self, X: torch.Tensor):
n, k = X.size(-2), X.size(-1)
if n != k:
raise ValueError(f"Expected a square matrix. Got a tensor of shape {X.shape}")
q, _ = torch.linalg.qr(X)
q = q / torch.linalg.det(q).pow(1 / n)
return q
def special_unitary(module: nn.Module, name: str = "weight") -> nn.Module:
weight = getattr(module, name, None)
if not isinstance(weight, torch.Tensor):
raise ValueError(f"Module '{module}' has no parameter or buffer '{name}'")
if weight.ndim < 2:
raise ValueError(f"Expected a matrix or batch of matrices. Got a tensor of {weight.ndim} dimensions.")
if weight.shape[-2] != weight.shape[-1]:
raise ValueError(f"Expected a square matrix or batch of square matrices. Got a tensor of shape {weight.shape}")
unit = _SpecialUnitary()
nn.utils.parametrize.register_parametrization(module, name, unit)
return module
class _Clamp(nn.Module):
def __init__(self, min, max):
super(_Clamp, self).__init__()
self.min = min
self.max = max
def forward(self, x):
if x.is_complex():
# clamp magnitude, ignore phase
return torch.clamp(x.abs(), self.min, self.max) * x / x.abs()
return torch.clamp(x, self.min, self.max)
def clamp(module: nn.Module, name: str = "scale", min=0, max=1) -> nn.Module:
scale = getattr(module, name, None)
if not isinstance(scale, torch.Tensor):
raise ValueError(f"Module '{module}' has no parameter or buffer '{name}'")
cl = _Clamp(min, max)
nn.utils.parametrize.register_parametrization(module, name, cl)
return module
class _EnergyConserving(nn.Module):
def __init__(self):
super(_EnergyConserving, self).__init__()
def forward(self, X: torch.Tensor):
if X.ndim == 2:
X = X.unsqueeze(0)
spectral_norm = torch.linalg.svdvals(X)[:, 0]
return (X / spectral_norm).squeeze()
def energy_conserving(module: nn.Module, name: str = "weight") -> nn.Module:
param = getattr(module, name, None)
if not isinstance(param, torch.Tensor):
raise ValueError(f"Module '{module}' has no parameter or buffer '{name}'")
if not (2 <= param.ndim <= 3):
raise ValueError(f"Expected a matrix or batch of matrices. Got a tensor of {param.ndim} dimensions.")
unit = _EnergyConserving()
nn.utils.parametrize.register_parametrization(module, name, unit)
return module
class ONN(nn.Module):
def __init__(self, input_dim, output_dim, dtype=None) -> None:
super(ONN, self).__init__()
self.input_dim = input_dim
self.output_dim = output_dim
self.dtype = dtype
self.dim = max(input_dim, output_dim)
# zero pad input to internal size if smaller
if self.input_dim < self.dim:
self.pad = lambda x: F.pad(x, ((self.dim - self.input_dim) // 2, (self.dim - self.input_dim + 1) // 2))
self.pad.__doc__ = f"Zero pad input from {self.input_dim} to {self.dim}"
else:
self.pad = lambda x: x
self.pad.__doc__ = f"Input size equals internal size {self.dim}"
# crop output to desired size
if self.output_dim < self.dim:
self.crop = lambda x: x[
:, (self.dim - self.output_dim) // 2 : (x.shape[1] - (self.dim - self.output_dim + 1) // 2)
]
self.crop.__doc__ = f"Crop output from {self.dim} to {self.output_dim}"
else:
self.crop = lambda x: x
self.crop.__doc__ = f"Output size equals internal size {self.dim}"
self.weight = nn.Parameter(torch.randn(self.dim, self.dim, dtype=self.dtype))
# self.scale = nn.Parameter(torch.randn(1, dtype=self.dtype.to_real())+0.5)
def reset_parameters(self):
q, _ = torch.linalg.qr(self.weight)
self.weight.data = q
# def get_M(self):
# return self.U @ self.sigma @ self.V
def forward(self, x):
return self.crop(self.pad(x) @ self.weight)
class ONNRect(nn.Module):
def __init__(self, input_dim, output_dim, square=False, dtype=None):
super(ONNRect, self).__init__()
self.input_dim = input_dim
self.output_dim = output_dim
if square:
dim = max(input_dim, output_dim)
self.weight = nn.Parameter(torch.randn(dim, dim, dtype=dtype))
# zero pad input to internal size if smaller
if self.input_dim < dim:
self.pad = lambda x: F.pad(x, ((dim - self.input_dim) // 2, (dim - self.input_dim + 1) // 2))
self.pad.__doc__ = f"Zero pad input from {self.input_dim} to {dim}"
else:
self.pad = lambda x: x
self.pad.__doc__ = f"Input size equals internal size {dim}"
# crop output to desired size
if self.output_dim < dim:
self.crop = lambda x: x[
:, (dim - self.output_dim) // 2 : (x.shape[1] - (dim - self.output_dim + 1) // 2)
]
self.crop.__doc__ = f"Crop output from {dim} to {self.output_dim}"
else:
self.crop = lambda x: x
self.crop.__doc__ = f"Output size equals internal size {dim}"
else:
self.weight = nn.Parameter(torch.randn(output_dim, input_dim, dtype=dtype))
self.pad = lambda x: x
self.pad.__doc__ = "No padding"
self.crop = lambda x: x
self.crop.__doc__ = "No cropping"
def forward(self, x):
x = self.pad(x).to(dtype=self.weight.dtype)
out = self.crop((self.weight @ x.mT).mT)
return out
class polarimeter(nn.Module):
def __init__(self):
super(polarimeter, self).__init__()
# self.input_length = input_length
def forward(self, data):
# S0 = I
# S1 = (2*I_x - I)/I
# S2 = (2*I_45 - I)/I
# S3 = (2*I_RHC - I)/I
# # data: (batch, input_length*2) -> (batch, input_length, 2)
data = data.view(data.shape[0], -1, 2)
x = data[:, :, 0].mean(dim=1)
y = data[:, :, 1].mean(dim=1)
# x = x.mean(dim=1)
# y = y.mean(dim=1)
# angle = torch.atan2(y.abs().square().real, x.abs().square().real)
# return torch.stack([angle, angle, angle, angle], dim=1)
# horizontal polarisation
I_x = x.abs().square()
# vertical polarisation
I_y = y.abs().square()
# 45 degree polarisation
I_45 = (x + y).abs().square()
# right hand circular polarisation
I_RHC = (x + 1j*y).abs().square()
# S0 = I_x + I_y
# S1 = I_x - I_y
# S2 = I_45 - I_m45
# S3 = I_RHC - I_LHC
S0 = (I_x + I_y)
S1 = ((2*I_x - S0)/S0)
S2 = ((2*I_45 - S0)/S0)
S3 = ((2*I_RHC - S0)/S0)
return torch.stack([S0/S0, S1/S0, S2/S0, S3/S0], dim=1)
class normalize_by_first(nn.Module):
def __init__(self):
super(normalize_by_first, self).__init__()
def forward(self, data):
return data / data[:, 0].unsqueeze(1)
class rotate(nn.Module):
def __init__(self):
super(rotate, self).__init__()
def forward(self, data, angle):
# data -> (batch, n*2)
# angle -> (batch, n)
data_ = data
if angle.ndim == 1:
angle_ = angle.unsqueeze(1)
else:
angle_ = angle
angle_ = angle_.expand(-1, data_.shape[1]//2)
c = torch.cos(angle_)
s = torch.sin(angle_)
rot = torch.stack([torch.stack([c, -s], dim=2),
torch.stack([s, c], dim=2)], dim=3)
d = torch.bmm(data_.reshape(-1, 1, 2), rot.view(-1, 2, 2).to(dtype=data_.dtype)).reshape(*data.shape)
# d = torch.bmm(data.unsqueeze(-1).mT, rot.to(dtype=data.dtype).mT).mT.squeeze(-1)
return d
class photodiode(nn.Module):
def __init__(self, size, bias=True):
super(photodiode, self).__init__()
self.input_dim = size
self.scale = nn.Parameter(torch.rand(size))
self.pd_bias = nn.Parameter(torch.rand(size))
def forward(self, x):
return x.abs().square().to(dtype=x.dtype.to_real()).mul(self.scale).add(self.pd_bias)
class input_rotator(nn.Module):
def __init__(self, input_dim):
super(input_rotator, self).__init__()
assert input_dim % 2 == 0, "Input dimension must be even"
self.input_dim = input_dim
# self.angle = nn.Parameter(torch.randn(1, dtype=self.dtype.to_real()))
def forward(self, x, angle=None):
# take channels (0,1), (2,3), ... and rotate them by the angle
angle = angle or self.angle
sine = torch.sin(angle)
cosine = torch.cos(angle)
rot = torch.tensor([[cosine, -sine], [sine, cosine]], dtype=self.dtype)
return torch.matmul(x.view(-1, 2), rot).view(x.shape)
# def __repr__(self):
# return f"ONNRect({self.input_dim}, {self.output_dim})"
# class SaturableAbsorberLambertW(nn.Module):
# """
# Implements the activation function for an optical saturable absorber
# base eqn: sigma*tau*I0 = 0.5*(log(Tm/T0))/(1-Tm),
# where: sigma is the absorption cross section
# tau is the radiative lifetime of the absorber material
# T0 is the initial transmittance
# I0 is the input intensity
# Tm is the transmittance of the absorber
# The activation function is defined as:
# Iout = I0 * Tm(I0)
# where Tm(I0) is the transmittance of the absorber as a function of the input intensity I0
# for a unit sigma*tau product, he solution Tm(I0) is given by:
# Tm(I0) = (W(2*exp(2*I0)*I0*T0))/(2*I0),
# where W is the Lambert W function
# if sigma*tau is not 1, I0 has to be scaled by sigma*tau
# (-> x has to be scaled by sqrt(sigma*tau))
# """
# def __init__(self, T0):
# super(SaturableAbsorberLambertW, self).__init__()
# self.register_buffer("T0", torch.tensor(T0))
# def forward(self, x: torch.Tensor):
# xc = x.conj()
# two_x_xc = (2 * x * xc).real
# return (lambertw(2 * torch.exp(two_x_xc) * (x * self.T0 * xc).real) / two_x_xc).to(dtype=x.dtype)
# def backward(self, x):
# xc = x.conj()
# lambert_eval = lambertw(2 * torch.exp(2 * x * xc).real * (x * self.T0 * xc).real)
# return (((xc * (-2 * lambert_eval + 2 * torch.square(x) - 1) + 2 * x * torch.square(xc) + x) * lambert_eval) / (
# 2 * torch.pow(x, 3) * xc * (lambert_eval + 1)
# )).to(dtype=x.dtype)
# class SaturableAbsorber(nn.Module):
# def __init__(self, alpha, I0):
# super(SaturableAbsorber, self).__init__()
# self.register_buffer("alpha", torch.tensor(alpha))
# self.register_buffer("I0", torch.tensor(I0))
# def forward(self, x):
# I = (x*x.conj()).to(dtype=x.dtype.to_real())
# A = self.alpha/(1+I/self.I0)
# class SpreadLayer(nn.Module):
# def __init__(self, in_features, out_features, dtype=None):
# super(SpreadLayer, self).__init__()
# self.in_features = in_features
# self.out_features = out_features
# self.mat = torch.ones(in_features, out_features, dtype=dtype)*torch.sqrt(torch.tensor(in_features/out_features))
# def forward(self, x):
# # N in_features -> M out_features, Enery is preserved (P = abs(x)^2)
# out = torch.matmul(x, self.mat)
# return out
#### as defined by zhang et alas
class DropoutComplex(nn.Module):
def __init__(self, p=0.5):
super(DropoutComplex, self).__init__()
self.dropout = nn.Dropout(p=p)
def forward(self, x):
if x.is_complex():
mask = self.dropout(torch.ones_like(x.real))
return x * mask
else:
return self.dropout(x)
class Scale(nn.Module):
def __init__(self, size):
super(Scale, self).__init__()
self.size = size
self.scale = nn.Parameter(torch.ones(size, dtype=torch.float32))
def forward(self, x):
return x * torch.sqrt(self.scale)
def __repr__(self):
return f"Scale({self.size})"
class Identity(nn.Module):
"""
implements the "activation" function
M(z) = z
"""
def __init__(self, size=None):
super(Identity, self).__init__()
def forward(self, x):
return x
class phase_shift(nn.Module):
def __init__(self, size):
super(phase_shift, self).__init__()
self.size = size
self.phase = nn.Parameter(torch.rand(size))
def forward(self, x):
return x * torch.exp(1j*self.phase)
class PowRot(nn.Module):
def __init__(self, bias=False):
super(PowRot, self).__init__()
self.scale = nn.Parameter(torch.tensor(1.0))
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x: torch.Tensor):
if x.is_complex():
return x * torch.exp(-self.scale * 1j * x.abs().square() + self.bias.to(dtype=x.dtype))
else:
return x
class MZISingle(nn.Module):
def __init__(self, bias, size, func=None):
super(MZISingle, self).__init__()
self.omega = nn.Parameter(torch.randn(size))
self.phi = nn.Parameter(torch.randn(size))
self.func = func or (lambda x: x.abs().square()) # default to |z|^2
def forward(self, x: torch.Tensor):
return x * torch.exp(1j * self.phi) * torch.sin(self.omega + self.func(x))
def naive_angle_loss(x: torch.Tensor, target: torch.Tensor, mod=2*torch.pi):
return torch.fmod((x.abs().real - target.abs().real), mod).abs().mean()
def cosine_loss(x: torch.Tensor, target: torch.Tensor):
return (2*(1 - torch.cos(x - target))).mean()
def angle_mse_loss(x: torch.Tensor, target: torch.Tensor):
x = torch.fmod(x, 2*torch.pi)
target = torch.fmod(target, 2*torch.pi)
x_cos = torch.cos(x)
x_sin = torch.sin(x)
target_cos = torch.cos(target)
target_sin = torch.sin(target)
cos_diff = x_cos - target_cos
sin_diff = x_sin - target_sin
squared_diff = cos_diff**2 + sin_diff**2
return squared_diff.mean()
class EOActivation(nn.Module):
def __init__(self, size=None):
# 10.1109/JSTQE.2019.2930455
super(EOActivation, self).__init__()
if size is None:
raise ValueError("Size must be specified")
self.size = size
self.alpha = nn.Parameter(torch.rand(size))
self.gain = nn.Parameter(torch.rand(size))
self.V_bias = nn.Parameter(torch.rand(size))
# self.register_buffer("gain", torch.ones(size))
# self.register_buffer("responsivity", torch.ones(size))
# self.register_buffer("V_pi", torch.ones(size))
self.reset_weights()
def reset_weights(self):
if "alpha" in self._parameters:
self.alpha.data = torch.rand(self.size)
# if "V_pi" in self._parameters:
# self.V_pi.data = torch.rand(self.size)*3
if "V_bias" in self._parameters:
self.V_bias.data = torch.randn(self.size)
if "gain" in self._parameters:
self.gain.data = torch.rand(self.size)
# if "responsivity" in self._parameters:
# self.responsivity.data = torch.ones(self.size)*0.9
# if "bias" in self._parameters:
# self.phase_bias.data = torch.zeros(self.size)
def forward(self, x: torch.Tensor):
phi_b = torch.pi * self.V_bias# / (self.V_pi)
g_phi = torch.pi * (self.alpha * self.gain)# * self.responsivity)# / (self.V_pi)
intermediate = g_phi * x.abs().square() + phi_b
return (
1j
* torch.sqrt(1 - self.alpha)
* torch.exp(-0.5j * intermediate)
* torch.cos(0.5 * intermediate)
* x
)
class Pow(nn.Module):
"""
implements the activation function
M(z) = ||z||^2 + b
"""
def __init__(self, bias=False):
super(Pow, self).__init__()
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x: torch.Tensor):
return x.abs().square().add(self.bias).to(dtype=x.dtype)
class Mag(nn.Module):
"""
implements the activation function
M(z) = ||z||+b
"""
def __init__(self, bias=False):
super(Mag, self).__init__()
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x: torch.Tensor):
return x.abs().add(self.bias).to(dtype=x.dtype)
class MagScale(nn.Module):
def __init__(self, bias=False):
super(MagScale, self).__init__()
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x: torch.Tensor):
return x.abs().add(self.bias).to(dtype=x.dtype).sin().mul(x)
class PowScale(nn.Module):
def __init__(self, bias=False):
super(PowScale, self).__init__()
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x: torch.Tensor):
return x.mul(x.abs().square().add(self.bias).to(dtype=x.dtype).sin())
class ModReLU(nn.Module):
"""
implements the activation function
M(z) = ReLU(||z|| + b)*exp(j*theta_z)
= ReLU(||z|| + b)*z/||z||
"""
def __init__(self, bias=True):
super(ModReLU, self).__init__()
if bias:
self.bias = nn.Parameter(torch.tensor(0.0))
else:
self.register_buffer("bias", torch.tensor(0.0))
def forward(self, x):
if x.is_complex():
mod = x.abs()
out = torch.relu(mod + self.bias) * x / mod
return out.to(dtype=x.dtype)
else:
return torch.relu(x + self.bias).to(dtype=x.dtype)
def __repr__(self):
return f"ModReLU(b={self.b})"
class CReLU(nn.Module):
"""
implements the activation function
M(z) = ReLU(Re(z)) + j*ReLU(Im(z))
"""
def __init__(self):
super(CReLU, self).__init__()
def forward(self, x):
if x.is_complex():
return torch.relu(x.real) + 1j * torch.relu(x.imag)
else:
return torch.relu(x)
class ZReLU(nn.Module):
"""
implements the activation function
M(z) = z if 0 <= angle(z) <= pi/2
= 0 otherwise
"""
def __init__(self):
super(ZReLU, self).__init__()
def forward(self, x):
if x.is_complex():
return x * (torch.angle(x) >= 0) * (torch.angle(x) <= torch.pi / 2)
else:
return torch.relu(x)
__all__ = [
complex_sse_loss,
complex_mse_loss,
angle_mse_loss,
UnitaryLayer,
unitary,
energy_conserving,
clamp,
ONN,
ONNRect,
DropoutComplex,
Identity,
Pow,
PowRot,
Mag,
ModReLU,
CReLU,
ZReLU,
MZISingle,
EOActivation,
photodiode,
phase_shift,
# SaturableAbsorberLambertW,
# SaturableAbsorber,
# SpreadLayer,
]