netket.optimizer.qgt.QGTOnTheFly(vstate=None, **kwargs)[source]

Lazy representation of an S Matrix computed by performing 2 jvp and 1 vjp products, using the variational state’s model, the samples that have already been computed, and the vector.

The S matrix is not computed yet, but can be computed by calling to_dense. The details on how the ⟨S⟩⁻¹⟨F⟩ system is solved are contaianed in the field sr.

  • vstate – The variational State.

  • centered – Uses S=⟨ΔÔᶜΔÔ⟩ if True (default), S=⟨ÔᶜΔÔ⟩ otherwise. The two forms are mathematically equivalent, but might lead to different results due to numerical precision. The non-centered variant should be approximately 33% faster.

Return type