quantumrevivals2d_tests.cpp

Go to the documentation of this file.

/**
 * @file quantumrevivals2d_tests.cpp
 * @brief Implements regression and invariant tests for quantumrevivals2d tests.
 * @ingroup qpe_tests
 *
 * Source: @c tests/quantumrevivals2d_tests.cpp. This file is part of Quantum Phenomena Explorer (QPE),
 * maintained by Officina Turini. See LICENSE_IT.txt / LICENSE.txt for the
 * QPE freeware source-available terms and THIRD_PARTY_NOTICES.txt for
 * third-party components.
 */
 
#include "quantumrevivals2d_tests.h"
 
#include "core/quantum/gaussianpacket2d.h"
#include "core/quantum/quantumrevivals2d.h"
 
#include <cmath>
 
namespace qpe {
namespace tests {
namespace {
 
/**
 * @brief Creates box.
 */
PotentialScene2D makeBox()
{
    PotentialScene2D scene;
    const float half = 3.2f;
    const float thickness = 1.28f;
    const float centre = half + 0.5f * thickness;
    const float span = 2.0f * (half + thickness);
    for (int sign = -1; sign <= 1; sign += 2) {
        PotentialObject2D vertical;
        vertical.type = PotentialObjectType2D::Rectangle;
        vertical.value = 120.0f;
        vertical.centerX = sign * centre;
        vertical.centerY = 0.0f;
        vertical.width = thickness;
        vertical.height = span;
        scene.add(vertical);
 
        PotentialObject2D horizontal;
        horizontal.type = PotentialObjectType2D::Rectangle;
        horizontal.value = 120.0f;
        horizontal.centerX = 0.0f;
        horizontal.centerY = sign * centre;
        horizontal.width = span;
        horizontal.height = thickness;
        scene.add(horizontal);
    }
    return scene;
}
 
/**
 * @brief Performs close.
 * @param a The a value used by the operation.
 * @param b The b value used by the operation.
 * @param tolerance The tolerance value used by the operation.
 */
bool close(double a, double b, double tolerance)
{
    return std::fabs(a - b) <= tolerance;
}
 
} // namespace
 
/**
 * @brief Runs quantum revivals2 d tests.
 * @param errorMessage The error message value used by the operation.
 */
bool runQuantumRevivals2DTests(std::string &errorMessage)
{
    errorMessage.clear();
    const PotentialScene2D scene = makeBox();
    QuantumBoxGeometry2D geometry;
    if (!QuantumRevivals2D::identifyBox(scene, geometry, nullptr)) {
        errorMessage = "failed to identify valid revival box";
        return false;
    }
    if (!close(geometry.innerWidth, 6.4, 1.0e-5) ||
        !close(geometry.innerHeight, 6.4, 1.0e-5) ||
        !close(geometry.wallPotential, 120.0, 1.0e-6)) {
        errorMessage = "revival box geometry is incorrect";
        return false;
    }
 
    const double expected = 4.0 * 6.4 * 6.4 / 3.14159265358979323846;
    if (!close(QuantumRevivals2D::revivalTimeX(geometry, 1.0), expected, 1.0e-5) ||
        !close(QuantumRevivals2D::revivalTimeY(geometry, 1.0), expected, 1.0e-5)) {
        errorMessage = "hard-wall revival time is incorrect";
        return false;
    }
 
    ComplexField2D field(32u, 32u, 0.25f, 0.25f);
    GaussianPacket2DParams packet;
    packet.centerX = -0.75f;
    packet.centerY = 0.25f;
    packet.sigma = 0.6f;
    packet.momentumX = 1.2f;
    packet.momentumY = -0.7f;
    GaussianPacket2D::initialize(field, packet);
 
    if (!close(QuantumRevivals2D::fidelity(field, field), 1.0, 1.0e-12)) {
        errorMessage = "self fidelity is not one";
        return false;
    }
 
    const std::vector<float> marginal = QuantumRevivals2D::marginalProbabilityX(field);
    if (marginal.size() != field.width()) {
        errorMessage = "wrong marginal size";
        return false;
    }
    double marginalNorm = 0.0;
    for (float value : marginal) marginalNorm += value * field.dx();
    if (!close(marginalNorm, field.norm2(), 2.0e-6)) {
        errorMessage = "x marginal does not integrate to field norm";
        return false;
    }
 
    QuantumRevivalHistory2D history(4u);
    if (!history.captureReference(field) || !history.append(0.0, field)) {
        errorMessage = "failed to capture/append revival history";
        return false;
    }
    if (history.size() != 1u || !close(history.samples()[0].fidelity, 1.0, 1.0e-12)) {
        errorMessage = "initial revival history sample is inconsistent";
        return false;
    }
 
    PotentialScene2D invalid = scene;
    PotentialObject2D circle;
    circle.type = PotentialObjectType2D::Circle;
    circle.value = 1.0f;
    circle.radius = 1.0f;
    invalid.add(circle);
    QuantumBoxGeometry2D invalidGeometry;
    if (QuantumRevivals2D::identifyBox(invalid, invalidGeometry, nullptr)) {
        errorMessage = "invalid mixed scene accepted as revival box";
        return false;
    }
 
    return true;
}
 
} // namespace tests
} // namespace qpe