49 lines
6.4 KiB
Plaintext
49 lines
6.4 KiB
Plaintext
---
|
||
title: pes_samplers (v0.26)
|
||
description: API reference for qiskit.chemistry.algorithms.pes_samplers in qiskit v0.26
|
||
in_page_toc_min_heading_level: 2
|
||
python_api_type: module
|
||
python_api_name: qiskit.chemistry.algorithms.pes_samplers
|
||
---
|
||
|
||
<span id="module-qiskit.chemistry.algorithms.pes_samplers" />
|
||
|
||
<span id="qiskit-chemistry-algorithms-pes-samplers" />
|
||
|
||
<span id="potential-energy-surface-samplers-qiskit-chemistry-algorithms-pes-samplers" />
|
||
|
||
# Potential energy surface samplers
|
||
|
||
`qiskit.chemistry.algorithms.pes_samplers`
|
||
|
||
Potential energy surface samplers.
|
||
|
||
Algorithms that can compute potential energy surfaces.
|
||
|
||
| | |
|
||
| ------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
|
||
| [`BOPESSampler`](qiskit.chemistry.algorithms.pes_samplers.BOPESSampler "qiskit.chemistry.algorithms.pes_samplers.BOPESSampler") | Class to evaluate the Born-Oppenheimer Potential Energy Surface (BOPES). |
|
||
|
||
When used with variational solvers, such as VQE, when computing a set of points there is support for extrapolation from prior solution(s) to bootstrap the algorithm with a better starting point to facilitate convergence. Extrapolators are:
|
||
|
||
> | | |
|
||
> | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|
||
> | [`Extrapolator`](qiskit.chemistry.algorithms.pes_samplers.Extrapolator "qiskit.chemistry.algorithms.pes_samplers.Extrapolator") | This class is based on performing extrapolation of parameters of a wavefunction for a variational algorithm defined in the variational forms as part of the Qiskit Aqua module. |
|
||
> | [`DifferentialExtrapolator`](qiskit.chemistry.algorithms.pes_samplers.DifferentialExtrapolator "qiskit.chemistry.algorithms.pes_samplers.DifferentialExtrapolator") | An extrapolator based on treating each param set as a point in space, and fitting a Hamiltonian which evolves each point to the next. |
|
||
> | [`PCAExtrapolator`](qiskit.chemistry.algorithms.pes_samplers.PCAExtrapolator "qiskit.chemistry.algorithms.pes_samplers.PCAExtrapolator") | A wrapper extrapolator which reduces the points’ dimensionality with PCA, performs extrapolation in the transformed pca space, and inverse transforms the results before returning. |
|
||
> | [`PolynomialExtrapolator`](qiskit.chemistry.algorithms.pes_samplers.PolynomialExtrapolator "qiskit.chemistry.algorithms.pes_samplers.PolynomialExtrapolator") | An extrapolator based on fitting each parameter to a polynomial function of a user-specified degree. |
|
||
> | [`SieveExtrapolator`](qiskit.chemistry.algorithms.pes_samplers.SieveExtrapolator "qiskit.chemistry.algorithms.pes_samplers.SieveExtrapolator") | A wrapper extrapolator which clusters the parameter values - either before extrapolation, after, or both - into two large and small clusters, and sets the small clusters’ parameters to zero. |
|
||
> | [`WindowExtrapolator`](qiskit.chemistry.algorithms.pes_samplers.WindowExtrapolator "qiskit.chemistry.algorithms.pes_samplers.WindowExtrapolator") | An extrapolator which wraps another extrapolator, limiting the internal extrapolator’s ground truth parameter set to a fixed window size. |
|
||
|
||
There is also a set of support function for potentials:
|
||
|
||
> | | |
|
||
> | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------- |
|
||
> | [`EnergySurface1DSpline`](qiskit.chemistry.algorithms.pes_samplers.EnergySurface1DSpline "qiskit.chemistry.algorithms.pes_samplers.EnergySurface1DSpline") | A simple cubic spline interpolation for the potential energy surface. |
|
||
> | [`HarmonicPotential`](qiskit.chemistry.algorithms.pes_samplers.HarmonicPotential "qiskit.chemistry.algorithms.pes_samplers.HarmonicPotential") | Implements a 1D Harmonic potential. |
|
||
> | [`MorsePotential`](qiskit.chemistry.algorithms.pes_samplers.MorsePotential "qiskit.chemistry.algorithms.pes_samplers.MorsePotential") | Implements a 1D Morse potential. |
|
||
> | [`EnergySurfaceBase`](qiskit.chemistry.algorithms.pes_samplers.EnergySurfaceBase "qiskit.chemistry.algorithms.pes_samplers.EnergySurfaceBase") | Class to hold a potential energy surface |
|
||
> | [`PotentialBase`](qiskit.chemistry.algorithms.pes_samplers.PotentialBase "qiskit.chemistry.algorithms.pes_samplers.PotentialBase") | Class to hold prescribed 1D potentials (e.g. |
|
||
> | [`VibronicStructureBase`](qiskit.chemistry.algorithms.pes_samplers.VibronicStructureBase "qiskit.chemistry.algorithms.pes_samplers.VibronicStructureBase") | Class to hold a molecular vibronic structure providing access to vibrational modes and energy levels. |
|
||
|