libtrilinos-rol-dev 12.10.1-3 / usr / include / trilinos / ROL_BinaryFunctions.hpp

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#ifndef ROL_BINARYFUNCTIONS_H
#define ROL_BINARYFUNCTIONS_H

#include "ROL_Elementwise_Function.hpp"

namespace ROL {
namespace Elementwise {

// Used to set every element in a vector to a specific value
template<class Real>
class Multiply : public BinaryFunction<Real> {
public:
  Multiply( ) { }

  Real apply( const Real &x, const Real &y ) const {
    return x*y;
  }  
}; // class Multiply

template<class Real>
class Plus : public BinaryFunction<Real> {
public:
  Real apply( const Real &x, const Real &y ) const {
    return x+y;
  }
};


// Used to set every element in a vector to a specific value
template<class Real>
class Divide : public BinaryFunction<Real> {
public:
  Divide( ) { }

  Real apply( const Real &x, const Real &y ) const {
    return x/y;
  }  
}; // class Divide


template<class Real> 
class Axpy : public BinaryFunction<Real> {
private:
  Real a_;
public:
  Axpy(Real a) : a_(a) {}
  Real apply( const Real &x, const Real &y ) const {
    return x+a_*y;
  }
};


template<class Real> 
class Aypx : public BinaryFunction<Real> {
private:
  Real a_;
public:
  Aypx(Real a) : a_(a) {}
  Real apply( const Real &x, const Real &y ) const {
    return a_*x+y;
  }
};


template<class Real>
class Min : public BinaryFunction<Real> {
public:
  Min() {}
  Real apply(const Real &x, const Real &y) const {
    return std::min(x,y);
  }
};


template<class Real>
class Max : public BinaryFunction<Real> {
public:
  Max() {}
  Real apply(const Real &x, const Real &y) const {
    return std::max(x,y);
  }
};


template<class Real> 
class Set : public BinaryFunction<Real> {
public:
  Real apply( const Real &x, const Real &y ) const {
    return y;
  }
};

template<class Real> 
class Lesser : public BinaryFunction<Real> {
public:
  Real apply( const Real &x, const Real &y ) const {
    return (x<y) ? x : y;
  }
};

template<class Real> 
class Greater : public BinaryFunction<Real> {
public:
  Real apply( const Real &x, const Real &y ) const {
    return (x>y) ? x : y;
  }
};

// Set x to one of two values based on whether y satisfies
// a comparative condition
template<class Real>
class ValueSet : public BinaryFunction<Real> {
private:
  const Real threshold_;
  const int option_;
  const Real c1_;
  const Real c2_;
public:
  static const int LESS_THAN    = 0;
  static const int EQUAL_TO     = 1;
  static const int GREATER_THAN = 2;
  ValueSet( const Real& threshold, const int option, const Real &c1=Real(1), const Real &c2=Real(0) ) :
    threshold_(threshold), option_(option), c1_(c1), c2_(c2) {}
 
  Real apply(const Real &x, const Real &y ) const {
    Real result(c2_);
    switch( option_ ) {
      case LESS_THAN:    { result = y <  threshold_ ? c1_ : c2_; break; }
      case EQUAL_TO:     { result = y == threshold_ ? c1_ : c2_; break; }
      case GREATER_THAN: { result = y >  threshold_ ? c1_ : c2_; break; }
    }
    return result;
  }
};


// Evaluate g(f(x,y))
template<class Real> 
class BinaryComposition : public BinaryFunction<Real> {

private:

  Teuchos::RCP<BinaryFunction<Real> > f_;
  Teuchos::RCP<UnaryFunction<Real> >  g_;

public:

  BinaryComposition( Teuchos::RCP<BinaryFunction<Real> > &f,
                     Teuchos::RCP<UnaryFunction<Real> > &g ) : f_(f), g_(g) {}
  Real apply( const Real &x, const Real &y ) const {
    return g_->apply(f_->apply(x,y));
  }

};


} // namespace Elementwise
} // namespace ROL




#endif // ROL_BINARYFUNCTIONS_H