ABinary.h

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#ifndef OPAL_ABinary_HH
#define OPAL_ABinary_HH
 
// ------------------------------------------------------------------------
// $RCSfile: ABinary.h,v $
// ------------------------------------------------------------------------
// $Revision: 1.2 $
// ------------------------------------------------------------------------
// Copyright: see Copyright.readme
// ------------------------------------------------------------------------
//
// Template class: ABinary<T,U>
//
// ------------------------------------------------------------------------
//
// $Date: 2002/01/17 22:18:36 $
// $Author: jsberg $
//
// ------------------------------------------------------------------------
 
#include <cerrno>
#include <iosfwd>
#include <vector>
#include "Expressions/AList.h"
#include "Expressions/TFunction2.h"
#include "Utilities/DomainError.h"
#include "Utilities/OpalException.h"
#include "Utilities/OverflowError.h"
 
namespace Expressions {
 
    // Template class ABinary
    // ----------------------------------------------------------------------
    //  The expression first evaluates the two array operands, and then
    //  loops in parallel over the results and applies the given function
    //  to each pair of components.
 
    template <class T, class U>
    class ABinary : public AList<T> {
    public:
        //  Use scalar function with two operands and two array expressions.
        ABinary(const TFunction2<T, U>& function, PtrToArray<U> left, PtrToArray<U> right);
 
        ABinary(const ABinary<T, U>&);
        virtual ~ABinary();
 
        virtual OArray<T>* clone() const;
 
        virtual std::vector<T> evaluate() const;
 
        virtual void print(std::ostream& str, int precedence = 99) const;
 
    private:
        // Not implemented.
        ABinary();
        void operator=(const ABinary&);
 
        // The operation object.
        const TFunction2<T, U>& fun;
 
        // The two operands.
        PtrToArray<U> lft;
        PtrToArray<U> rgt;
    };
 
    // Implementation
    // ----------------------------------------------------------------------
 
    template <class T, class U>
    inline ABinary<T, U>::ABinary(const ABinary& rhs)
        : AList<T>(), fun(rhs.fun), lft(rhs.lft->clone()), rgt(rhs.rgt->clone()) {}
 
    template <class T, class U>
    inline ABinary<T, U>::ABinary(
            const TFunction2<T, U>& function, PtrToArray<U> left, PtrToArray<U> right)
        : AList<T>(), fun(function), lft(left), rgt(right) {}
 
    template <class T, class U>
    inline ABinary<T, U>::~ABinary() {}
 
    template <class T, class U>
    inline OArray<T>* ABinary<T, U>::clone() const {
        return new ABinary<T, U>(*this);
    }
 
    template <class T, class U>
    inline std::vector<T> ABinary<T, U>::evaluate() const {
        errno              = 0;
        std::vector<U> op1 = lft->evaluate();
        std::vector<U> op2 = rgt->evaluate();
        std::vector<T> result;
 
        if (op1.size() == op2.size()) {
            for (typename std::vector<U>::size_type i = 0; i < op1.size(); ++i) {
                result.push_back((*fun.function)(op1[i], op2[i]));
            }
        } else if (op1.size() == 1) {
            for (typename std::vector<U>::size_type i = 0; i < op2.size(); ++i) {
                result.push_back((*fun.function)(op1[0], op2[i]));
            }
        } else if (op2.size() == 1) {
            for (typename std::vector<U>::size_type i = 0; i < op1.size(); ++i) {
                result.push_back((*fun.function)(op1[i], op2[0]));
            }
        } else {
            throw OpalException("ABinary::evaluate()", "Inconsistent array dimensions.");
        }
 
        // Test for run-time evaluation errors.
        switch (errno) {
            case EDOM:
                throw DomainError("ABinary::evaluate()");
 
            case ERANGE:
                throw OverflowError("ABinary::evaluate()");
 
            default:
                return result;
        }
    }
 
    template <class T, class U>
    inline void ABinary<T, U>::print(std::ostream& os, int precedence) const {
        if (fun.precedence >= 0) {
            // Binary operation.
            if (fun.precedence <= precedence) os << "(";
            lft->print(os, fun.precedence - 1);
            os << fun.name;
            rgt->print(os, fun.precedence);
            if (fun.precedence <= precedence) os << ")";
        } else {
            // Function.
            os << fun.name << '(';
            lft->print(os, 0);
            os << ',';
            rgt->print(os, 0);
            os << ')';
        }
    }
 
}  // namespace Expressions
 
#endif  // OPAL_ABinary_HH