Files
FCES-native/src/spectral.cpp

42 lines
1.2 KiB
C++

#include "fces/spectral.hpp"
#include <numeric>
namespace fces {
SpectralSensor::SpectralSensor(torch::nn::Module& /*model*/) {}
void SpectralSensor::track_layer(const std::string& name, const torch::Tensor& weight) {
if (weight.dim() >= 2) {
layer_ranks_[name] = compute_effective_rank(weight);
}
}
float SpectralSensor::get_global_rank() const {
if (layer_ranks_.empty()) return 0.0f;
float sum = 0.0f;
for (const auto& [_, rank] : layer_ranks_) {
sum += rank;
}
return sum / static_cast<float>(layer_ranks_.size());
}
void SpectralSensor::reset() {
layer_ranks_.clear();
}
float SpectralSensor::compute_effective_rank(const torch::Tensor& weight) {
// SVD-based effective rank (Shannon entropy of normalized singular values)
auto svd_result = torch::svd(weight.to(torch::kFloat32));
auto svd = std::get<1>(svd_result);
auto s = svd / svd.sum();
auto log_s = (s + 1e-10f).log();
float entropy = -s.mul(log_s).sum().item<float>();
return std::exp(entropy);
}
float SpectralController::compute_alpha(float global_rank, float grokking_coefficient) const {
return global_rank * grokking_coefficient;
}
} // namespace fces