#ifndef __JMATRIX1D__
#define __JMATRIX1D__

#include <limits>
#include <cmath>
#include <ostream>
#include <iomanip>

#include "JIO/JSerialisable.hh"
#include "JLang/JEquals.hh"
#include "JLang/JManip.hh"
#include "JMath/JMath.hh"


/**
 * \author mdejong
 */

namespace JMATH {}
namespace JPP { using namespace JMATH; }

namespace JMATH {

  using JIO::JReader;
  using JIO::JWriter;
  using JLANG::JEquals;
  

  /**
   * 1 x 1 matrix
   */
  class JMatrix1D :
    public JMath  <JMatrix1D>,
    public JEquals<JMatrix1D>
  {
  public:

    using JMath<JMatrix1D>::mul;
    
    
    /**
     * Default constructor.
     */
    JMatrix1D() :
      a00(0.0)
    {}


    /**
     * Contructor.
     *
     * \param   __a00   (0,0)
     */
    JMatrix1D(const double __a00) :
      a00(__a00)
    {}


    /**
     * Get reference to unique instance of this class object.
     *
     * \return          zero matrix
     */
    static const JMatrix1D& getInstance()
    {
      static JMatrix1D matrix;

      return matrix;
    }


    /**
     * Set to identity matrix.
     *
     * \return          this matrix
     */
    JMatrix1D& setIdentity()
    {
      a00 = 1.0;

      return *this;
    }


    /**
     * Get reference to unique instance of this class object.
     *
     * \return          identity matrix
     */
    static const JMatrix1D& getIdentity()
    {
      static JMatrix1D matrix(JMatrix1D().setIdentity());

      return matrix;
    }


    /**
     * Set matrix.
     *
     * \param  A        matrix
     */
    void set(const JMatrix1D& A)
    {
      static_cast<JMatrix1D&>(*this) = A;
    }


    /**
     * Set matrix to the null matrix.
     *
     * \return          this matrix
     */
    JMatrix1D& reset()
    {
      *this = JMatrix1D();
      
      return *this;
    }

    
    /**
     * Transpose.
     *
     * \return          this matrix
     */
    JMatrix1D& transpose()
    {
      return *this;
    }


    /**
     * Negate matrix.
     *
     * \return          -this matrix
     */
    JMatrix1D& negate()
    {
      a00 = -a00;

      return *this;
    }


    /**
     * Matrix addition.
     *
     * \param  A        matrix
     * \return          this matrix + A
     */
    JMatrix1D& add(const JMatrix1D& A)
    {
      a00 += A.a00;

      return *this;
    }


    /**
     * Matrix subtraction.
     *
     * \param  A        matrix
     * \return          this matrix - A
     */
    JMatrix1D& sub(const JMatrix1D& A)
    {
      a00 -= A.a00;

      return *this;
    }


    /**
     * Scale matrix.
     *
     * \param  factor   factor
     * \return          this matrix * factor
     */
    JMatrix1D& mul(const double factor)
    {
      a00 *= factor;

      return *this;
    }


    /**
     * Scale matrix.
     *
     * \param  factor   factor
     * \return          this matrix / factor
     */
    JMatrix1D& div(const double factor)
    {
      a00 /= factor;

      return *this;
    }

    
    /**
     * Matrix multiplication.
     *
     * \param  A        matrix
     * \param  B        matrix
     * \return          this matrix
     */
    JMatrix1D& mul(const JMatrix1D& A,
                   const JMatrix1D& B)
    {
      a00 = A.a00 * B.a00;
      
      return *this;
    }


    /**
     * Equality.
     *
     * \param  A        matrix
     * \param  eps      numerical precision
     * \return          true if matrices identical; else false
     */
    bool equals(const JMatrix1D& A,
		const double     eps = std::numeric_limits<double>::min()) const
    {
      return (fabs(a00 - A.a00) <= eps);
    }


    /**
     * Test identity.
     *
     * \param  eps      numerical precision
     * \return          true if identity matrix; else false
     */
    bool isIdentity(const double eps = std::numeric_limits<double>::min()) const
    {
      return equals(getIdentity(), eps);
    }


    /**
     * Get determinant of matrix.
     *
     * \return         determinant of matrix
     */
    double getDeterminant() const
    {
      return a00;
    }


    /**
     * Transform.
     *
     * \param  __x      x value
     */
    void transform(double& __x) const
    {
      __x = a00 * __x;
    }


    /**
     * Read matrix from input.
     *
     * \param  in       reader
     * \param  matrix   matrix
     * \return          reader
     */
    friend inline JReader& operator>>(JReader& in, JMatrix1D& matrix)
    {
      in >> matrix.a00;

      return in;
    }


    /**
     * Write matrix to output.
     *
     * \param  out      writer
     * \param  matrix   matrix
     * \return          writer
     */
    friend inline JWriter& operator<<(JWriter& out, const JMatrix1D& matrix)
    {
      out << matrix.a00;

      return out;
    }


    /**
     * Print ASCII formatted output.
     *
     * \param  out      output stream
     * \param  A        matrix
     * \return          output stream
     */
    friend inline std::ostream& operator<<(std::ostream& out, const JMatrix1D& A)
    {
      using namespace std;

      const JFormat format(out, getFormat<JMatrix1D>(JFormat_t(10, 3, std::ios::fixed | std::ios::showpos)));

      out << format << A.a00 << endl;

      return out;
    }


    double a00;
  };
}

#endif