MOAB: Mesh Oriented datABase  (version 5.3.1)
MBMesquite::PatchPowerMeanP Class Reference

Objective function: p-mean^p of p-mean^p of patch metric values. More...

#include <PatchPowerMeanP.hpp>

+ Inheritance diagram for MBMesquite::PatchPowerMeanP:
+ Collaboration diagram for MBMesquite::PatchPowerMeanP:

Public Member Functions

MESQUITE_EXPORT PatchPowerMeanP (double power, QualityMetric *qm=0)
MESQUITE_EXPORT PatchPowerMeanP (const PatchPowerMeanP &copy)
 copy constructor
virtual MESQUITE_EXPORT ~PatchPowerMeanP ()
virtual MESQUITE_EXPORT bool initialize_block_coordinate_descent (Mesh *mesh, MeshDomain *domain, const Settings *settings, PatchSet *user_set, MsqError &err)
virtual MESQUITE_EXPORT bool evaluate (EvalType type, PatchData &pd, double &value_out, bool free, MsqError &err)
 Evaluate objective function for specified patch.
virtual MESQUITE_EXPORT bool evaluate_with_gradient (EvalType type, PatchData &pd, double &value_out, std::vector< Vector3D > &grad_out, MsqError &err)
 Evaluate objective function and gradient for specified patch.
virtual MESQUITE_EXPORT bool evaluate_with_Hessian (EvalType type, PatchData &pd, double &value_out, std::vector< Vector3D > &grad_out, MsqHessian &Hessian_out, MsqError &err)
 Evaluate objective function and Hessian for specified patch.
virtual MESQUITE_EXPORT
ObjectiveFunction
clone () const
 Create copy with same state.

Detailed Description

Objective function: p-mean^p of p-mean^p of patch metric values.

Definition at line 45 of file PatchPowerMeanP.hpp.


Constructor & Destructor Documentation

Parameters:
powerThe exponent to use for the power-mean
qmThe quality metric.

Definition at line 53 of file PatchPowerMeanP.hpp.

Referenced by clone().

: PMeanPTemplate( power, qm ) {}

copy constructor

Define a copy constructor because the compiler-provided default one would also copy the temporary arrays, which would be a waste of time.

Definition at line 62 of file PatchPowerMeanP.hpp.

: PMeanPTemplate( copy ) {}

Definition at line 65 of file PatchPowerMeanP.hpp.

{}

Member Function Documentation

Create copy with same state.

Create a new instance of the objective function that is a copy of the callee with the same accumulated values, parameters, etc.

Reimplemented from MBMesquite::PMeanPTemplate.

Definition at line 43 of file PatchPowerMeanP.cpp.

References PatchPowerMeanP().

{
    return new PatchPowerMeanP( *this );
}
bool MBMesquite::PatchPowerMeanP::evaluate ( EvalType  type,
PatchData pd,
double &  value_out,
bool  free,
MsqError err 
) [virtual]

Evaluate objective function for specified patch.

Either evaluate the objective function over the passed patch or update the accumulated, global objective function value for changes in the passed patch, depending on the value of the EvalType.

Parameters:
typeEvaluation type.
pdThe patch.
value_outThe passed-back value of the objective fuction.
freeIf true, incorporate the quality metric values only for those metric evaluations that depend on at least one free vertex
Returns:
false if any QualityMetric evaluation returned false, true otherwise.

Reimplemented from MBMesquite::PMeanPTemplate.

Definition at line 70 of file PatchPowerMeanP.cpp.

References MBMesquite::ObjectiveFunction::ACCUMULATE, MBMesquite::QualityMetric::evaluate(), MBMesquite::QualityMetric::get_evaluations(), MBMesquite::QualityMetric::get_negate_flag(), MBMesquite::ObjectiveFunctionTemplate::get_quality_metric(), MBMesquite::QualityMetric::get_single_pass(), MBMesquite::PMeanPTemplate::get_value(), MBMesquite::PMeanPTemplate::mPower, MSQ_CHKERR, MSQ_ERRFALSE, MBMesquite::PMeanPTemplate::qmHandles, MBMesquite::Exponent::raise(), and value().

Referenced by initialize_block_coordinate_descent().

{
    QualityMetric* qm = get_quality_metric();
    if( type == ObjectiveFunction::ACCUMULATE )
        qm->get_single_pass( pd, qmHandles, free, err );
    else
        qm->get_evaluations( pd, qmHandles, free, err );
    MSQ_ERRFALSE( err );

    // calculate OF value for just the patch
    std::vector< size_t >::const_iterator i;
    double value, working_sum = 0.0;
    for( i = qmHandles.begin(); i != qmHandles.end(); ++i )
    {
        bool result = qm->evaluate( pd, *i, value, err );
        if( MSQ_CHKERR( err ) || !result ) return false;

        working_sum += mPower.raise( value );
    }
    working_sum /= qmHandles.size();

    // get overall OF value, update member data, etc.
    size_t global_count;
    value_out = qm->get_negate_flag() * get_value( working_sum, 1, type, global_count );
    return true;
}
bool MBMesquite::PatchPowerMeanP::evaluate_with_gradient ( EvalType  eval_type,
PatchData pd,
double &  OF_val,
std::vector< Vector3D > &  grad,
MsqError err 
) [virtual]

Evaluate objective function and gradient for specified patch.

Either evaluate the objective function over the passed patch or update the accumulated, global objective function value for changes in the passed patch, depending on the value of the EvalType.

The default implementation of this function will use the value-only variation of the evaluate method and numerical approximation to calculate gradients. Whenever possible, objective function implementations should provide more efficient analyical gradient calculations.

Parameters:
typeEvaluation type.
pdThe patch.
value_outThe passed-back value of the objective fuction.
grad_outThe gradient of the OF wrt the coordinates of each *free* vertex in the patch.
Returns:
false if any QualityMetric evaluation returned false, true otherwise.

Numerically Calculates the gradient of the ObjectiveFunction for the free vertices in the patch. Returns 'false' if the patch is outside of a required feasible region, returns 'ture' otherwise. The behavior of the function depends on the value of the boolean useLocalGradient. If useLocalGradient is set to 'true', compute_numerical_gradient creates a sub-patch around a free vertex, and then perturbs that vertex in one of the coordinate directions. Only the ObjectiveFunction value on the local sub-patch is used in the computation of the gradient. Therefore, useLocalGradient should only be set to 'true' for ObjectiveFunctions which can use this method. Unless the concrete ObjectiveFunction sets useLocalGradient to 'true' in its constructor, the value will be 'false'. In this case, the objective function value for the entire patch is used in the calculation of the gradient. This is computationally expensive, but it is numerically correct for all (C_1) functions.

Parameters:
pdPatchData on which the gradient is taken.
gradArray of Vector3D of length the number of vertices used to store gradient.
OF_valwill be set to the objective function value.

Reimplemented from MBMesquite::PMeanPTemplate.

Definition at line 97 of file PatchPowerMeanP.cpp.

References MBMesquite::QualityMetric::evaluate_with_gradient(), MBMesquite::QualityMetric::get_evaluations(), MBMesquite::QualityMetric::get_negate_flag(), MBMesquite::ObjectiveFunctionTemplate::get_quality_metric(), MBMesquite::PMeanPTemplate::get_value(), MBMesquite::PMeanPTemplate::mGradient, MBMesquite::PMeanPTemplate::mIndices, MBMesquite::PMeanPTemplate::mPower, MSQ_CHKERR, MSQ_ERRFALSE, MBMesquite::PatchData::num_free_vertices(), MBMesquite::OF_FREE_EVALS_ONLY, MBMesquite::PMeanPTemplate::qmHandles, MBMesquite::Exponent::raise(), MBMesquite::Exponent::value(), and value().

{
    QualityMetric* qm = get_quality_metric();
    qm->get_evaluations( pd, qmHandles, OF_FREE_EVALS_ONLY, err );
    MSQ_ERRFALSE( err );

    // zero gradient
    grad_out.clear();
    grad_out.resize( pd.num_free_vertices(), Vector3D( 0.0, 0.0, 0.0 ) );

    // calculate OF value and gradient for just the patch
    std::vector< size_t >::const_iterator i;
    double value, working_sum = 0.0;
    const double f = qm->get_negate_flag() * mPower.value() / qmHandles.size();
    for( i = qmHandles.begin(); i != qmHandles.end(); ++i )
    {
        bool result = qm->evaluate_with_gradient( pd, *i, value, mIndices, mGradient, err );
        if( MSQ_CHKERR( err ) || !result ) return false;
        if( fabs( value ) < DBL_EPSILON ) continue;

        const double qmp = mPower.raise( value );
        working_sum += mPower.raise( value );
        value = f * qmp / value;

        for( size_t j = 0; j < mIndices.size(); ++j )
        {
            mGradient[j] *= value;
            grad_out[mIndices[j]] += mGradient[j];
        }
    }

    // get overall OF value, update member data, etc.
    size_t global_count;
    value_out          = qm->get_negate_flag() * get_value( working_sum, 1, type, global_count );
    const double inv_n = 1.0 / global_count;
    std::vector< Vector3D >::iterator g;
    for( g = grad_out.begin(); g != grad_out.end(); ++g )
        *g *= inv_n;
    return true;
}
bool MBMesquite::PatchPowerMeanP::evaluate_with_Hessian ( EvalType  type,
PatchData pd,
double &  value_out,
std::vector< Vector3D > &  grad_out,
MsqHessian Hessian_out,
MsqError err 
) [virtual]

Evaluate objective function and Hessian for specified patch.

Either evaluate the objective function over the passed patch or update the accumulated, global objective function value for changes in the passed patch, depending on the value of the EvalType.

The default implementation of this function will fail.

Parameters:
typeEvaluation type.
pdThe patch.
value_outThe passed-back value of the objective fuction.
grad_outThe gradient of the OF wrt the coordinates of each *free* vertex in the patch.
Hessian_outThe Hessian of the OF wrt the coordinates of each *free* vertex in the patch.
Returns:
false if any QualityMetric evaluation returned false, true otherwise.

Reimplemented from MBMesquite::PMeanPTemplate.

Definition at line 139 of file PatchPowerMeanP.cpp.

References MBMesquite::MsqHessian::add(), MBMesquite::QualityMetric::evaluate_with_Hessian(), MBMesquite::QualityMetric::get_evaluations(), MBMesquite::QualityMetric::get_negate_flag(), MBMesquite::ObjectiveFunctionTemplate::get_quality_metric(), MBMesquite::PMeanPTemplate::get_value(), MBMesquite::PMeanPTemplate::mGradient, MBMesquite::PMeanPTemplate::mHessian, MBMesquite::PMeanPTemplate::mIndices, MBMesquite::PMeanPTemplate::mPower, MSQ_CHKERR, MSQ_ERRFALSE, n, MBMesquite::PatchData::num_free_vertices(), MBMesquite::OF_FREE_EVALS_ONLY, MBMesquite::PMeanPTemplate::qmHandles, MBMesquite::Exponent::raise(), MBMesquite::MsqHessian::scale(), MBMesquite::Exponent::value(), value(), and MBMesquite::MsqHessian::zero_out().

{
    QualityMetric* qm = get_quality_metric();
    qm->get_evaluations( pd, qmHandles, OF_FREE_EVALS_ONLY, err );
    MSQ_ERRFALSE( err );

    // zero gradient and hessian
    grad_out.clear();
    grad_out.resize( pd.num_free_vertices(), 0.0 );
    Hessian_out.zero_out();

    // calculate OF value and gradient for just the patch
    std::vector< size_t >::const_iterator i;
    size_t j, k, n;
    double value, working_sum = 0.0;
    const double f1 = qm->get_negate_flag() * mPower.value() / qmHandles.size();
    const double f2 = f1 * ( mPower.value() - 1 );
    Matrix3D m;
    for( i = qmHandles.begin(); i != qmHandles.end(); ++i )
    {
        bool result = qm->evaluate_with_Hessian( pd, *i, value, mIndices, mGradient, mHessian, err );
        if( MSQ_CHKERR( err ) || !result ) return false;
        if( fabs( value ) < DBL_EPSILON ) continue;

        const double qmp = mPower.raise( value );
        const double hf  = f2 * qmp / ( value * value );
        const double gf  = f1 * qmp / value;
        working_sum += qmp;

        const size_t nfree = mIndices.size();
        n                  = 0;
        for( j = 0; j < nfree; ++j )
        {
            for( k = j; k < nfree; ++k )
            {
                m.outer_product( mGradient[j], mGradient[k] );
                m *= hf;
                mHessian[n] *= gf;
                m += mHessian[n];
                ++n;
                Hessian_out.add( mIndices[j], mIndices[k], m, err );
                MSQ_ERRFALSE( err );
            }
        }

        for( j = 0; j < nfree; ++j )
        {
            mGradient[j] *= gf;
            grad_out[mIndices[j]] += mGradient[j];
        }
    }

    // get overall OF value, update member data, etc.
    size_t global_count;
    value_out          = qm->get_negate_flag() * get_value( working_sum, 1, type, global_count );
    const double inv_n = 1.0 / global_count;
    std::vector< Vector3D >::iterator g;
    for( g = grad_out.begin(); g != grad_out.end(); ++g )
        *g *= inv_n;
    Hessian_out.scale( inv_n );
    return true;
}
bool MBMesquite::PatchPowerMeanP::initialize_block_coordinate_descent ( Mesh mesh,
MeshDomain domain,
const Settings settings,
PatchSet user_set,
MsqError err 
) [virtual]

Definition at line 48 of file PatchPowerMeanP.cpp.

References MBMesquite::ObjectiveFunction::ACCUMULATE, MBMesquite::PatchData::attach_settings(), b, MBMesquite::PMeanPTemplate::clear(), evaluate(), MBMesquite::PatchIterator::get_next_patch(), MSQ_CHKERR, MSQ_ERRZERO, MBMesquite::PatchData::set_domain(), MBMesquite::PatchData::set_mesh(), and value().

{
    clear();
    PatchIterator patches( patch_set );

    PatchData pd;
    pd.set_mesh( mesh );
    pd.set_domain( domain );
    if( settings ) pd.attach_settings( settings );

    bool result = true;
    while( patches.get_next_patch( pd, err ) && !MSQ_CHKERR( err ) )
    {
        double value;
        bool b = evaluate( ObjectiveFunction::ACCUMULATE, pd, value, false, err );
        MSQ_ERRZERO( err );
        result = result && b;
    }
    return result;
}

List of all members.


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