9
1
mirror of https://github.com/QuantumPackage/qp2.git synced 2024-08-30 12:43:40 +02:00
qp2/doc/intro/selected_ci.html
2019-01-25 14:17:34 +01:00

424 lines
26 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Selected Configuration Interaction &mdash; Quantum Package 2.0 documentation</title>
<link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
<link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
<link rel="next" title="Quick-start guide" href="../users_guide/quickstart.html" />
<link rel="prev" title="Installation" href="install.html" />
<script src="../_static/js/modernizr.min.js"></script>
</head>
<body class="wy-body-for-nav">
<div class="wy-grid-for-nav">
<nav data-toggle="wy-nav-shift" class="wy-nav-side">
<div class="wy-side-scroll">
<div class="wy-side-nav-search">
<a href="../index.html" class="icon icon-home"> Quantum Package
</a>
<div class="version">
2.0
</div>
<div role="search">
<form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
<input type="text" name="q" placeholder="Search docs" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
</div>
<div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
<p class="caption"><span class="caption-text">Introduction</span></p>
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="install.html">Installation</a></li>
<li class="toctree-l1 current"><a class="current reference internal" href="#">Selected Configuration Interaction</a><ul>
<li class="toctree-l2"><a class="reference internal" href="#simple-algorithm">Simple Algorithm</a></li>
<li class="toctree-l2"><a class="reference internal" href="#stochastic-approximations-for-the-selection-and-the-computation-of-ept">Stochastic approximations for the selection and the computation of <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span></a></li>
<li class="toctree-l2"><a class="reference internal" href="#deterministic-approximations-for-the-selection">Deterministic approximations for the selection</a></li>
<li class="toctree-l2"><a class="reference internal" href="#modifying-the-selection-space">Modifying the selection space</a></li>
</ul>
</li>
</ul>
<p class="caption"><span class="caption-text">User's guide</span></p>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/quickstart.html">Quick-start guide</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/interfaces.html">Interfaces</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/excited_states.html">Excited states</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/natural_orbitals.html">Natural orbitals</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/printing.html">Printing the near-<abbr title="Full Configuration Interaction">FCI</abbr> wave function</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/plugins.html">Working with external plugins</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/qp_plugins.html">qp_plugins</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/index.html">Index of commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="../users_guide/index.html#index-of-programs">Index of programs</a></li>
</ul>
<p class="caption"><span class="caption-text">Programmer's guide</span></p>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../programmers_guide/programming.html">Programming in the <em>Quantum Package</em></a></li>
<li class="toctree-l1"><a class="reference internal" href="../programmers_guide/ezfio.html">EZFIO</a></li>
<li class="toctree-l1"><a class="reference internal" href="../programmers_guide/plugins.html">Developing plugins</a></li>
<li class="toctree-l1"><a class="reference internal" href="../programmers_guide/index.html">Index for programmers</a></li>
<li class="toctree-l1"><a class="reference internal" href="../programmers_guide/plugins.html">Developing plugins</a></li>
</ul>
<p class="caption"><span class="caption-text">Appendix</span></p>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../appendix/benchmarks.html">Benchmarks</a></li>
<li class="toctree-l1"><a class="reference internal" href="../appendix/research.html">Some research made with the <em>Quantum Package</em></a></li>
<li class="toctree-l1"><a class="reference internal" href="../appendix/license.html">License</a></li>
<li class="toctree-l1"><a class="reference internal" href="../appendix/contributors.html">Contributors</a></li>
</ul>
</div>
</div>
</nav>
<section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
<nav class="wy-nav-top" aria-label="top navigation">
<i data-toggle="wy-nav-top" class="fa fa-bars"></i>
<a href="../index.html">Quantum Package</a>
</nav>
<div class="wy-nav-content">
<div class="rst-content">
<div role="navigation" aria-label="breadcrumbs navigation">
<ul class="wy-breadcrumbs">
<li><a href="../index.html">Docs</a> &raquo;</li>
<li>Selected Configuration Interaction</li>
<li class="wy-breadcrumbs-aside">
<a href="../_sources/intro/selected_ci.rst.txt" rel="nofollow"> View page source</a>
</li>
</ul>
<hr/>
</div>
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
<div itemprop="articleBody">
<div class="section" id="selected-configuration-interaction">
<h1>Selected Configuration Interaction<a class="headerlink" href="#selected-configuration-interaction" title="Permalink to this headline"></a></h1>
<p>These methods rely on the same principle as the usual <abbr title="Configuration Interaction">CI</abbr> approaches, except
that determinants arent chosen <em>a priori</em> based on an occupation or
excitation criterion, but selected <em>on the fly</em> among the entire set of
determinants based on their estimated contribution to the <abbr title="Full Configuration Interaction">FCI</abbr> wave function.
It has been noticed long ago that, even inside a predefined subspace of
determinants, only a small number significantly contributes to the wave
function. <a class="reference internal" href="#bytautas-2009" id="id1">[A1]</a><a class="reference internal" href="#anderson-2018" id="id2">[A2]</a> Therefore, an <em>on the fly</em>
selection of determinants is a rather natural idea that has been proposed
in the late 60s by Bender and Davidson <a class="reference internal" href="#bender-1969" id="id3">[A3]</a> as well as Whitten
and Hackmeyer. <a class="reference internal" href="#whitten-1969" id="id4">[A4]</a></p>
<p>The approach we are using in the <em>Quantum Package</em> is based on <abbr title="Configuration Interaction using a Perturbative Selection">CIPSI</abbr> developed by Huron,
Rancurel and Malrieu, <a class="reference internal" href="#huron-1973" id="id5">[A5]</a> that iteratively selects <em>external</em>
determinants (determinants which are not present in the variational space)
using a perturbative criterion.</p>
<p>There is however a computational downside. In <em>a priori</em> selected
methods, the rule by which determinants are selected is known <em>a
priori</em>, and therefore, one can map a particular determinant to some row or
column index. <a class="reference internal" href="#knowles-1984" id="id6">[A6]</a> As a consequence, it can be systematically
determined to which matrix element of <span class="math notranslate nohighlight">\(\hat H\)</span> a two-electron integral
contributes. This allows for the implementation of so-called
<em>integral-driven</em> methods, that work essentially by iterating over
integrals and are very fast.</p>
<p>On the contrary, in selected methods an explicit list of determinants has to be
kept, and there is no immediate way to know whether a determinant has been
selected, or what its index is in the list. Consequently, a
<em>determinant-driven</em> approach will be used, in which the loops run over
determinants rather than integrals. This can be a lot more computationally
expensive since the number of determinants is typically much larger than the
number of integrals.</p>
<p>What makes <em>determinant-driven</em> approaches possible here is:</p>
<ul class="simple">
<li>the fact that selected <abbr title="Configuration Interaction">CI</abbr> methods will keep the number of determinants small
enough, orders of magnitude smaller than in <em>a priori</em> selected methods for
wave functions with equal energies,</li>
<li>an efficient way to compare determinants in order to extract the
corresponding excitation operators <a class="reference internal" href="#scemama-2013" id="id7">[A7]</a>,</li>
<li>an intense filtering of the internal space to avoid as much as possible
determinant comparisons of disconnected determinants,</li>
<li>a fast retrieval of the corresponding two-electron integrals in memory.</li>
</ul>
<div class="section" id="simple-algorithm">
<h2>Simple Algorithm<a class="headerlink" href="#simple-algorithm" title="Permalink to this headline"></a></h2>
<p>The variational wave function <span class="math notranslate nohighlight">\(|\Psi^{(n)}\rangle\)</span> is defined over a set of determinants
<span class="math notranslate nohighlight">\(\{|D_I\rangle\}^{(n)}\)</span> in which we diagonalize <span class="math notranslate nohighlight">\(\hat H\)</span>.</p>
<div class="math notranslate nohighlight">
\[|\Psi^{(n)}\rangle = \sum_{I} c_I^{(n)} |D_I\rangle\]</div>
<p>The determinants in <span class="math notranslate nohighlight">\(\{|D_I\rangle\}^{(n)}\)</span> will be characterized as <strong>internal</strong>.</p>
<ol class="arabic">
<li><p class="first">For all <strong>external</strong> determinants <span class="math notranslate nohighlight">\(|\alpha \rangle\)</span> <span class="math notranslate nohighlight">\(\notin\)</span> <span class="math notranslate nohighlight">\(\{|D_I\rangle\}^{(n)}\)</span>, compute the
Epstein-Nesbet second-order perturbative contribution to the energy</p>
<div class="math notranslate nohighlight">
\[e_\alpha = \frac{ \langle \Psi^{(n)}| {\hat H} | \alpha \rangle^2 }{E^{(n)} - \langle \alpha | {\hat H} | \alpha \rangle }.\]</div>
<p><span class="math notranslate nohighlight">\(E^{(n)}\)</span> is the variational energy of the wave function at the current
iteration. Note that another perturbation theory could be used to estimate
<span class="math notranslate nohighlight">\(e_\alpha\)</span>.</p>
</li>
<li><p class="first">An estimate of the total missing correlation energy can be computed
by summing all the <span class="math notranslate nohighlight">\(e_\alpha\)</span> contributions</p>
<div class="math notranslate nohighlight">
\[\begin{split}E_\text{PT2} &amp; = \sum_{\alpha} e_\alpha \\
E_\text{FCI} &amp; \approx E + E_\text{PT2}\end{split}\]</div>
</li>
<li><p class="first"><span class="math notranslate nohighlight">\(\{ |\alpha \rangle \}_\star ^{(n)}\)</span>, the subset of determinants <span class="math notranslate nohighlight">\(|\alpha \rangle\)</span> with the largest
contributions <span class="math notranslate nohighlight">\(e_\alpha\)</span>, is added to the variational space</p>
<div class="math notranslate nohighlight">
\[\{ |D_I \rangle \}^{(n+1)} = \{|D_I\rangle\}^{(n)} \cup \{ |\alpha\rangle \}_\star^{(n)}\]</div>
</li>
<li><p class="first">Go to iteration n+1, or exit on some criterion (number of determinants in
the wave function, low <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span>, …).</p>
</li>
</ol>
<p>Of course, such a procedure can be applied on any state and therefore can allow to treat both ground and excited states.</p>
</div>
<div class="section" id="stochastic-approximations-for-the-selection-and-the-computation-of-ept">
<h2>Stochastic approximations for the selection and the computation of <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span><a class="headerlink" href="#stochastic-approximations-for-the-selection-and-the-computation-of-ept" title="Permalink to this headline"></a></h2>
<p>The simple algorithm would be too slow to make calculations possible. Instead,
the <em>Quantum Package</em> uses a stochastic algorithm <a class="reference internal" href="../appendix/research.html#garniron-2017-2" id="id8">[13]</a> in order to compute
efficiently the <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span> and to select on-the-fly the best Slater determinants.</p>
<p>In such a way, the selection step introduces no extra cost with respect to the <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span> calculation and the <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span>
itself is unbiased but associated with a statistical error bar rapidly converging.</p>
</div>
<div class="section" id="deterministic-approximations-for-the-selection">
<h2>Deterministic approximations for the selection<a class="headerlink" href="#deterministic-approximations-for-the-selection" title="Permalink to this headline"></a></h2>
<p>The following description was used in a previous version of the <abbr title="Configuration Interaction using a Perturbative Selection">CIPSI</abbr> algorithm
which was less efficient. Nonetheless, it introduces the notions of <strong>generator</strong> and <strong>selector</strong> determinants
which are much more general than the <abbr title="Configuration Interaction using a Perturbative Selection">CIPSI</abbr> algorithm that targets the <abbr title="Full Configuration Interaction">FCI</abbr> and can be used to realize virtually
<strong>any kind of CI in a selected way</strong>.</p>
<p>We define <strong>generator</strong> determinants, as determinants of the internal space
from which the <span class="math notranslate nohighlight">\(|\alpha \rangle\)</span> are generated.
We then define <strong>selector</strong> determinants, a truncated wave function
used in the computation of <span class="math notranslate nohighlight">\(e_\alpha\)</span>.</p>
<p>For calculations in the <abbr title="Full Configuration Interaction">FCI</abbr> space, the determinants are sorted by decreasing
<span class="math notranslate nohighlight">\(|c_I|^2\)</span>, and thresholds are used on the squared norm of the wave function.
The default is to use <a class="reference internal" href="../modules/determinants.html#cmdoption-determinants-arg-threshold-generators"><code class="xref std std-option docutils literal notranslate"><span class="pre">determinants</span> <span class="pre">threshold_generators</span></code></a> = 0.99 for
the generators, and <code class="xref std std-option docutils literal notranslate"><span class="pre">determinants</span> <span class="pre">threshold_selectors</span></code> = 0.999 for the
selectors.</p>
<p>This is nothing but the 3-class <abbr title="Configuration Interaction using a Perturbative Selection">CIPSI</abbr> approximation to accelerate the selection,
<a class="reference internal" href="#evangelisti-1983" id="id9">[A8]</a> where instead of generating all possible <span class="math notranslate nohighlight">\(|\alpha \rangle\)</span>,
we only generate a subset which are likely to be selected.</p>
<p>The computation of <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span> using a truncated wave function is biased,
so if an accurate estimate of the <abbr title="Full Configuration Interaction">FCI</abbr> energy is desired, it is preferable
to recompute <span class="math notranslate nohighlight">\(E_\text{PT2}\)</span> with the hybrid deterministic/stochastic algorithm
<a class="reference internal" href="#garniron-2017b" id="id10">[A9]</a> which is unbiased (this is the default).</p>
</div>
<div class="section" id="modifying-the-selection-space">
<h2>Modifying the selection space<a class="headerlink" href="#modifying-the-selection-space" title="Permalink to this headline"></a></h2>
<p>By changing the definition of generators, and the rules for the generation of
the <span class="math notranslate nohighlight">\(|\alpha \rangle\)</span>, it is easy to define selected variants of traditional <abbr title="Configuration Interaction">CI</abbr> methods.</p>
<p>For example, if one defines the <abbr title="Hartree-Fock">HF</abbr> determinant as the only generator,
one will produce a selected <abbr title="Configuration Interaction with Single and Double Excitations">CISD</abbr>. If one also changes the rules for the generation
to generate only the double excitations, one will have a selected <abbr title="Configuration Interaction with Double Excitations">CID</abbr>.</p>
<p>The generators can also be chosen as determinants belonging to a <abbr title="Complete Active Space">CAS</abbr>. If the
rules allow only for excitations inside the <abbr title="Complete Active Space">CAS</abbr>, we obtain a selected
<abbr title="Complete Active Space">CAS</abbr> <abbr title="Configuration Interaction">CI</abbr>. If the rules allow for excitations in the <abbr title="Full Configuration Interaction">FCI</abbr> space, we obtain
a selected <abbr title="Complete Active Space plus all Singles and Doubles">CAS-SD</abbr>. And if one add the rule to prevent for doing double
excitations with two holes and two particles outside of the active space, one
obtains a selected <abbr title="Difference Dedicated Configuration Interaction">DDCI</abbr> method.</p>
<p>All such things can be done very easily when programming the <em>Quantum Package</em>.</p>
<hr class="docutils" />
<p id="bibtex-bibliography-intro/selected_ci-0"><table class="docutils citation" frame="void" id="bytautas-2009" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id1">[A1]</a></td><td>Laimutis Bytautas and Klaus Ruedenberg. A priori identification of configurational deadwood. <em>Chemical Physics</em>, 356(1-3):6475, feb 2009. URL: <a class="reference external" href="https://doi.org/10.1016%2Fj.chemphys.2008.11.021">https://doi.org/10.1016%2Fj.chemphys.2008.11.021</a>, <a class="reference external" href="https://doi.org/10.1016/j.chemphys.2008.11.021">doi:10.1016/j.chemphys.2008.11.021</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="anderson-2018" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id2">[A2]</a></td><td>James&nbsp;S.M. Anderson, Farnaz Heidar-Zadeh, and Paul&nbsp;W. Ayers. Breaking the curse of dimension for the electronic schrodinger equation with functional analysis. <em>Computational and Theoretical Chemistry</em>, 1142:6677, oct 2018. URL: <a class="reference external" href="https://doi.org/10.1016%2Fj.comptc.2018.08.017">https://doi.org/10.1016%2Fj.comptc.2018.08.017</a>, <a class="reference external" href="https://doi.org/10.1016/j.comptc.2018.08.017">doi:10.1016/j.comptc.2018.08.017</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="bender-1969" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id3">[A3]</a></td><td>Charles&nbsp;F. Bender and Ernest&nbsp;R. Davidson. Studies in configuration interaction: the first-row diatomic hydrides. <em>Phys. Rev.</em>, 183(1):2330, jul 1969. URL: <a class="reference external" href="http://dx.doi.org/10.1103/PhysRev.183.23">http://dx.doi.org/10.1103/PhysRev.183.23</a>, <a class="reference external" href="https://doi.org/10.1103/physrev.183.23">doi:10.1103/physrev.183.23</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="whitten-1969" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id4">[A4]</a></td><td>J.&nbsp;L. Whitten and Melvyn Hackmeyer. Configuration interaction studies of ground and excited states of polyatomic molecules. i. the CI formulation and studies of formaldehyde. <em>The Journal of Chemical Physics</em>, 51(12):55845596, dec 1969. URL: <a class="reference external" href="https://doi.org/10.1063%2F1.1671985">https://doi.org/10.1063%2F1.1671985</a>, <a class="reference external" href="https://doi.org/10.1063/1.1671985">doi:10.1063/1.1671985</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="huron-1973" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id5">[A5]</a></td><td>B.&nbsp;Huron, J.&nbsp;P. Malrieu, and P.&nbsp;Rancurel. Iterative perturbation calculations of ground and excited state energies from multiconfigurational zeroth-order wavefunctions. <em>The Journal of Chemical Physics</em>, 58(12):57455759, jun 1973. URL: <a class="reference external" href="https://doi.org/10.1063%2F1.1679199">https://doi.org/10.1063%2F1.1679199</a>, <a class="reference external" href="https://doi.org/10.1063/1.1679199">doi:10.1063/1.1679199</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="knowles-1984" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id6">[A6]</a></td><td>Peter&nbsp;J. Knowles and Nicholas&nbsp;C Handy. A new determinant-based full configuration interaction method. <em>Chem. Phys. Letters</em>, 111:315321, 1984.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="scemama-2013" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id7">[A7]</a></td><td>A.&nbsp;Scemama and E.&nbsp;Giner. An efficient implementation of Slater-Condon rules. <em>ArXiv [physics.comp-ph]</em>, pages 1311.6244, November 2013. URL: <a class="reference external" href="https://arxiv.org/abs/1311.6244">https://arxiv.org/abs/1311.6244</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="evangelisti-1983" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id9">[A8]</a></td><td>Stefano Evangelisti, Jean-Pierre Daudey, and Jean-Paul Malrieu. Convergence of an improved CIPSI algorithm. <em>Chemical Physics</em>, 75(1):91102, feb 1983. URL: <a class="reference external" href="https://doi.org/10.1016%2F0301-0104%2883%2985011-3">https://doi.org/10.1016%2F0301-0104%2883%2985011-3</a>, <a class="reference external" href="https://doi.org/10.1016/0301-0104(83)85011-3">doi:10.1016/0301-0104(83)85011-3</a>.</td></tr>
</tbody>
</table>
<table class="docutils citation" frame="void" id="garniron-2017b" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id10">[A9]</a></td><td>Yann Garniron, Anthony Scemama, Pierre-François Loos, and Michel Caffarel. Hybrid stochastic-deterministic calculation of the second-order perturbative contribution of multireference perturbation theory. <em>The Journal of Chemical Physics</em>, 147(3):034101, jul 2017. URL: <a class="reference external" href="https://doi.org/10.1063%2F1.4992127">https://doi.org/10.1063%2F1.4992127</a>, <a class="reference external" href="https://doi.org/10.1063/1.4992127">doi:10.1063/1.4992127</a>.</td></tr>
</tbody>
</table>
</p>
</div>
</div>
</div>
</div>
<footer>
<div class="rst-footer-buttons" role="navigation" aria-label="footer navigation">
<a href="../users_guide/quickstart.html" class="btn btn-neutral float-right" title="Quick-start guide" accesskey="n" rel="next">Next <span class="fa fa-arrow-circle-right"></span></a>
<a href="install.html" class="btn btn-neutral" title="Installation" accesskey="p" rel="prev"><span class="fa fa-arrow-circle-left"></span> Previous</a>
</div>
<hr/>
<div role="contentinfo">
<p>
&copy; Copyright 2018, A. Scemama, E. Giner
</p>
</div>
Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/rtfd/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
</footer>
</div>
</div>
</section>
</div>
<script type="text/javascript" id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script>
<script type="text/javascript" src="../_static/jquery.js"></script>
<script type="text/javascript" src="../_static/underscore.js"></script>
<script type="text/javascript" src="../_static/doctools.js"></script>
<script async="async" type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
<script type="text/javascript" src="../_static/js/theme.js"></script>
<script type="text/javascript">
jQuery(function () {
SphinxRtdTheme.Navigation.enable(true);
});
</script>
</body>
</html>