/**
 *  @file Array.h
 *
 *  Header file for class Array2D
 */

/*
 *  $Author$
 *  $Revision$
 *  $Date$
 */

// Copyright 2001  California Institute of Technology


#ifndef CT_ARRAY_H
#define CT_ARRAY_H

#include "ct_defs.h"
#include "ctexceptions.h"
#include "stringUtils.h"
#include "utilities.h"

namespace Cantera { 


    /**
     *  A class for 2D arrays stored in column-major
     *  (Fortran-compatible) form.
     */
    class Array2D {

    public:

        typedef vector_fp::iterator iterator;
        typedef vector_fp::const_iterator const_iterator;

        /**
         * Default constructor. Create an empty array.
         */
        Array2D() : m_nrows(0), m_ncols(0) { m_data.clear(); }


        /** 
         *  Constructor. Create an \c m by \c n array, and initialize
         *  all elements to \c v.
         */
        Array2D(int m, int n, doublereal v = 0.0) 
            : m_nrows(m), m_ncols(n) {
            m_data.resize(n*m);
            fill(m_data.begin(), m_data.end(), v);
        }

        /// copy constructor
        Array2D(const Array2D& y) {
            m_nrows = y.m_nrows;
            m_ncols = y.m_ncols;
            m_data.resize(m_nrows*m_ncols);
            m_data = y.m_data;
        }

        /// assignment operator
        Array2D& operator=(const Array2D& y) {
            if (&y == this) return *this;
            m_nrows = y.m_nrows;
            m_ncols = y.m_ncols;
            m_data.resize(m_nrows*m_ncols);
            m_data = y.m_data;
	    return *this;
        }

        /// resize the array, and fill the new entries with 'v'
        void resize(int n, int m, doublereal v = 0.0) {
            m_nrows = n;
            m_ncols = m;
            m_data.resize(n*m, v);
        }

        /// append a column
        void appendColumn(const vector_fp& c) {
            m_ncols++;
            m_data.resize(m_nrows*m_ncols);
            int m;
            for (m = 0;  m < m_nrows; m++) value(m_ncols, m) = c[m];
        }

        /// append a column
        void appendColumn(doublereal* c) {
            m_ncols++;
            m_data.resize(m_nrows*m_ncols);
            int m;
            for (m = 0;  m < m_nrows; m++) value(m_ncols, m) = c[m];
        }

        /// set the nth row to array rw
        void setRow(int n, doublereal* rw) {
            for (int j = 0; j < m_ncols; j++) {
                m_data[m_nrows*j + n] = rw[j];
            }
        }

        /// get the nth row
        void getRow(int n, doublereal* rw) {
            for (int j = 0; j < m_ncols; j++) {
                rw[j] = m_data[m_nrows*j + n];
            }
        }

        /// set the values in column m to those in array col
        void setColumn(int m, doublereal* col) {
            for (int i = 0; i < m_nrows; i++) {
                m_data[m_nrows*m + i] = col[i];
            }
        }

        /// get the values in column m
        void getColumn(int m, doublereal* col) {
            for (int i = 0; i < m_nrows; i++) {
                col[i] = m_data[m_nrows*m + i];
            }
        }
                
        /**
         * Destructor. Does nothing, since no memory allocated on the
         * heap.
         */
        virtual ~Array2D(){}


        /**
         * Evaluate a*x + y.
         */
        void axpy(doublereal a, const Array2D& x, const Array2D& y) {
            const doublereal* xb = x.begin();
            const doublereal* yb = y.begin();
            doublereal* b = begin();
            for (; b != end(); ++b, ++xb, ++yb)  *b = a*(*xb) + *yb;
        }

        /**
         * Allows setting elements using the syntax A(i,j) = x.
         */ 
        doublereal& operator()( int i, int j) { return value(i,j); }

        /**
         * Allows retrieving elements using the syntax x = A(i,j).
         */ 
        doublereal operator() ( int i, int j) const {return value(i,j);}

        doublereal& value( int i, int j) {return m_data[m_nrows*j + i];}
        doublereal value( int i, int j) const {return m_data[m_nrows*j + i];}

        /// Number of rows
        size_t nRows() const { return m_nrows; }

        /// Number of columns
        size_t nColumns() const { return m_ncols; }

        /// Return an iterator pointing to the first element
        iterator begin() { return m_data.begin(); }

        /// Return an iterator pointing past the last element
        iterator end() { return m_data.end(); }

        /// Return a const iterator pointing to the first element
        const_iterator begin() const { return m_data.begin(); }

        /// Return a const iterator pointing to past the last element
        const_iterator end() const { return m_data.end(); }

        /// Return a reference to the data vector
        vector_fp& data() { return m_data; }

        /// Return a const reference to the data vector
        const vector_fp& data() const { return m_data; }

	/// Return a pointer to the top of column j, columns are contiguous
	/// in memory
	doublereal * ptrColumn(int j) { return &(m_data[m_nrows*j]); }

    protected:

        vector_fp m_data;
        int m_nrows, m_ncols;
    };

    /// output the array
    inline ostream& operator<<(ostream& s, const Array2D& m) {
        int nr = static_cast<int>(m.nRows());
        int nc = static_cast<int>(m.nColumns());
        int i,j;
        for (i = 0; i < nr; i++) {
            for (j = 0; j < nc; j++) {
                s << m(i,j) << ", ";
            }
            s << endl;
        }
        return s;
    }

    inline void operator*=(Array2D& m, doublereal a) {
        scale(m.begin(), m.end(), m.begin(), a);
    }

    inline void operator+=(Array2D& x, const Array2D& y) {
        sum_each(x.begin(), x.end(), y.begin());
    }

}

#endif