lib/maths/common/CIntegration.cc

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 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0 and the following additional limitation. Functionality enabled by the
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 * limitation.
 */

#include <maths/common/CIntegration.h>

#include <core/CLogger.h>

namespace ml {
namespace maths {
namespace common {
const double* CIntegration::CGaussLegendreQuadrature::weights(EOrder order) {
    switch (order) {
    case OrderOne:
        return WEIGHTS1;
    case OrderTwo:
        return WEIGHTS2;
    case OrderThree:
        return WEIGHTS3;
    case OrderFour:
        return WEIGHTS4;
    case OrderFive:
        return WEIGHTS5;
    case OrderSix:
        return WEIGHTS6;
    case OrderSeven:
        return WEIGHTS7;
    case OrderEight:
        return WEIGHTS8;
    case OrderNine:
        return WEIGHTS9;
    case OrderTen:
        return WEIGHTS10;
    }

    LOG_ABORT(<< "Unexpected enumeration value " << order);
}

const double* CIntegration::CGaussLegendreQuadrature::abscissas(EOrder order) {
    switch (order) {
    case OrderOne:
        return ABSCISSAS1;
    case OrderTwo:
        return ABSCISSAS2;
    case OrderThree:
        return ABSCISSAS3;
    case OrderFour:
        return ABSCISSAS4;
    case OrderFive:
        return ABSCISSAS5;
    case OrderSix:
        return ABSCISSAS6;
    case OrderSeven:
        return ABSCISSAS7;
    case OrderEight:
        return ABSCISSAS8;
    case OrderNine:
        return ABSCISSAS9;
    case OrderTen:
        return ABSCISSAS10;
    }

    LOG_ABORT(<< "Unexpected enumeration value " << order);
}

const double CIntegration::CGaussLegendreQuadrature::WEIGHTS1[] = {2.0};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS2[] = {1.0, 1.0};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS3[] = {
    0.8888888888888888, 0.5555555555555556, 0.5555555555555556};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS4[] = {
    0.6521451548625461, 0.6521451548625461, 0.3478548451374538, 0.3478548451374538};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS5[] = {
    0.5688888888888889, 0.4786286704993665, 0.4786286704993665,
    0.2369268850561891, 0.2369268850561891};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS6[] = {
    0.3607615730481386, 0.3607615730481386, 0.4679139345726910,
    0.4679139345726910, 0.1713244923791704, 0.1713244923791704};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS7[] = {
    0.4179591836734694, 0.3818300505051189, 0.3818300505051189,
    0.2797053914892766, 0.2797053914892766, 0.1294849661688697,
    0.1294849661688697};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS8[] = {
    0.3626837833783620, 0.3626837833783620, 0.3137066458778873,
    0.3137066458778873, 0.2223810344533745, 0.2223810344533745,
    0.1012285362903763, 0.1012285362903763};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS9[] = {
    0.3302393550012598, 0.1806481606948574, 0.1806481606948574,
    0.0812743883615744, 0.0812743883615744, 0.3123470770400029,
    0.3123470770400029, 0.2606106964029354, 0.2606106964029354};
const double CIntegration::CGaussLegendreQuadrature::WEIGHTS10[] = {
    0.2955242247147529, 0.2955242247147529, 0.2692667193099963,
    0.2692667193099963, 0.2190863625159820, 0.2190863625159820,
    0.1494513491505806, 0.1494513491505806, 0.0666713443086881,
    0.0666713443086881};

const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS1[] = {0.0};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS2[] = {
    -0.5773502691896257, 0.5773502691896257};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS3[] = {
    0.0000000000000000, -0.7745966692414834, 0.7745966692414834};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS4[] = {
    -0.3399810435848563, 0.3399810435848563, -0.8611363115940526, 0.8611363115940526};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS5[] = {
    0.0000000000000000, -0.5384693101056831, 0.5384693101056831,
    -0.9061798459386640, 0.9061798459386640};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS6[] = {
    0.6612093864662645, -0.6612093864662645, -0.2386191860831969,
    0.2386191860831969, -0.9324695142031521, 0.9324695142031521};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS7[] = {
    0.0000000000000000,  0.4058451513773972, -0.4058451513773972,
    -0.7415311855993945, 0.7415311855993945, -0.9491079123427585,
    0.9491079123427585};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS8[] = {
    -0.1834346424956498, 0.1834346424956498,  -0.5255324099163290,
    0.5255324099163290,  -0.7966664774136267, 0.7966664774136267,
    -0.9602898564975363, 0.9602898564975363};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS9[] = {
    0.0000000000000000,  -0.8360311073266358, 0.8360311073266358,
    -0.9681602395076261, 0.9681602395076261,  -0.3242534234038089,
    0.3242534234038089,  -0.6133714327005904, 0.6133714327005904};
const double CIntegration::CGaussLegendreQuadrature::ABSCISSAS10[] = {
    -0.1488743389816312, 0.1488743389816312,  -0.4333953941292472,
    0.4333953941292472,  -0.6794095682990244, 0.6794095682990244,
    -0.8650633666889845, 0.8650633666889845,  -0.9739065285171717,
    0.9739065285171717};

core::CFastMutex CIntegration::ms_Mutex;
}
}
}