C++ CMatrix类设计与实现
作者：互联网
实验一：CMatrix类设计与实现
一 代码实现
1.main.cpp
#include < iostream>
#include <stdio.h>
#include "CMatrix.h"
using namespace std;
int main(int argc, char** argv) {
double pData[10]={2,3,4,5};
CMatrix m1,m2(2,5,pData), m3("d:\\1.txt"),m4(m2);
cin>>m1;
m2.Set(1,3,10);
cout<<m1<<m2<<m3<<m4;
m4=m3;
m4[2]=m4+1;
if(m4==m3)
{
cout<<"Error !"<<endl;
}
m4 += m3;
cout<<"sum of m4 = "<<(double)m4<<endl;
return 0;
}
2.CMatrix.h
#ifndef CMATRIX_H
#define CMATRIX_H
#include <iostream>
using namespace std;
class CMatrix
{
public:
CMatrix();
CMatrix(int nRow, int nCol, double* pData = NULL);
CMatrix(const CMatrix & m);
CMatrix(const char* strPath);
~CMatrix();
bool Create(int nRow, int nCol, double* pData = NULL);
void Set(int nRow, int nCol, double dVale);
void Release();
friend istream & operator>>(istream& is, CMatrix& m);
friend ostream & operator<<(ostream & os, const CMatrix & m);
CMatrix & operator=(const CMatrix & m);
CMatrix & operator+=(const CMatrix & m);
// CMatrix& operator+(const CMatrix& m);
// CMatrix operator+(const CMatrix& m1,const CMatrix& m2);
double& operator[](int nIndex);
double& operator()(int nRow, int nCol);
bool operator ==(const CMatrix & m);
bool operator !=(const CMatrix & m);
operator double();
private:
int m_nRow;
int m_nCol;
double* m_pData;
};
CMatrix operator+(const CMatrix & m1, const CMatrix & m2);
inline void CMatrix::Set(int nRow, int nCol, double dVal)
{
m_pData[nRow * m_nCol + nCol] = dVal;
}
#endif
3.CMatrix.cpp
#include "CMatrix.h"
#include <fstream>
#include <assert.h>
CMatrix::CMatrix() : m_nRow(0), m_nCol(0), m_pData(0)
{
}
CMatrix::CMatrix(int nRow, int nCol, double* pData) : m_pData(0)
{
Create(nRow, nCol, pData);
}
CMatrix::CMatrix(const CMatrix & m) : m_pData(0)
{
*this = m;
}
CMatrix::CMatrix(const char* strPath)
{
m_pData = 0;
m_nRow = m_nCol = 0;
ifstream cin(strPath);
cin >> *this;
}
CMatrix::~CMatrix()
{
Release();
}
bool CMatrix::Create(int nRow, int nCol, double* pData)
{
Release();
m_pData = new double[nRow * nCol];
m_nRow = nRow;
m_nCol = nCol;
if (pData)
{
memcpy(m_pData, pData, nRow * nCol * sizeof(double));
}
}
void CMatrix::Release()
{
if (m_pData)
{
delete[]m_pData;
m_pData = NULL;
}
m_nRow = m_nCol = 0;
}
CMatrix & CMatrix::operator=(const CMatrix & m)
{
if (this != &m) {
Create(m.m_nRow, m.m_nCol, m.m_pData);
}
return *this;
}
CMatrix & CMatrix::operator+=(const CMatrix & m)
{
assert(m_nRow == m.m_nRow && m_nCol == m.m_nCol);
for (int i = 0; i < m_nRow * m_nCol; i++)
{
m_pData[i] += m.m_pData[i];
}
return *this;
}
//CMatrix& CMatrix::operator+(const CMatrix& m)
//{
// assert(m_nRow==m.m_nRow && m_nCol==m.m_nCol);
// for(int i=0;i<m_nRow*m_nCol;i++)
// {
// m_pData[i]+=m.m_pData[i];
// }
// return *this;
//}
//CMatrix CMatrix::operator+(const CMatrix& m1,const CMatrix& m2)
//{
// CMatrix m3(m1);
// m3+=m2;
// return m3;
//}
CMatrix operator+(const CMatrix & m1, const CMatrix & m2)
{
CMatrix m3(m1);
m3 += m2;
return m3;
}
double& CMatrix::operator[](int nIndex)
{
assert(nIndex < m_nRow * m_nCol);
return m_pData[nIndex];
}
double& CMatrix::operator()(int nRow, int nCol)
{
assert(nRow * m_nCol + nCol < m_nRow * m_nCol);
return m_pData[nRow * m_nCol + nCol];
}
bool CMatrix::operator == (const CMatrix & m)
{
if (!(m_nRow == m.m_nRow && m_nCol == m.m_nCol))
{
return false;
}
for (int i = 0; i < m_nRow * m_nCol; i++)
{
if (m_pData[i] != m.m_pData[i])
{
return false;
}
}
return true;
}
bool CMatrix::operator !=(const CMatrix & m)
{
return !((*this) == m);
}
CMatrix::operator double()
{
double dS = 0;
for (int i = 0; i < m_nRow * m_nCol; i++)
{
dS += m_pData[i];
}
return dS;
}
istream & operator>>(istream& is, CMatrix& m)
{
is >> m.m_nRow >> m.m_nCol;
m.Create(m.m_nRow, m.m_nCol);
for (int i = 0; i < m.m_nRow * m.m_nCol; i++)
{
is >> m.m_pData[i];
}
return is;
}
ostream & operator<<(ostream & os, const CMatrix & m)
{
os << m.m_nRow << " " << m.m_nCol << endl;
double* pData = m.m_pData;
for (int i = 0; i < m.m_nRow; i++)
{
for (int j = 0; j < m.m_nCol; j++)
{
os << *pData++ << " ";
}
os << endl;
}
return os;
}
二 运行截图
输入1 1 3
文件1.txt中内容也为 1 1 3
三 总结
1.构造函数
CMatrix();
CMatrix(int nRow, int nCol, double* pData=NULL);
CMatrix(const CMatrix& m);
CMatrix(const char* strPath);
1.可以有多个构造函数进行构造（可以重载）
2.double* pData=NULL 无pData传入时默认进行赋值null
2.析构函数
~CMatrix();
1 析构函数不可以有参数，因此不可以发生重载
2.程序在对象销毁前会自动调用析构，无须手动调用，并且只会调用一次
3.运算符重载
CMatrix & operator+=(const CMatrix & m);
double& operator[](int nIndex);
double& operator()(int nRow, int nCol);
bool operator ==(const CMatrix & m);
bool operator !=(const CMatrix & m);
operator double();
1.运算符重载，可以将类的运算规则自定义
2 返回值用 类型+& 是为了避免做连续运算时候会出错.原因就是没加&你返回的不是地址而是被Copy了一个临时对象
3 转换函数默认返回类型为它本身
4.友元函数
friend istream & operator>>(istream& is, CMatrix& m);
friend ostream & operator<<(ostream & os, const CMatrix & m);
1.在类中声明友元函数使其可以访问类的私有数据
2.friend和operator同时使用可以让其他类对数据进行的操作符进行自定义
标签：nRow,CMatrix,int,pData,C++,nCol,operator,设计 来源： https://blog.csdn.net/sjdkljlkfc/article/details/120585539