c++矩阵
这里讲的矩阵有创建矩阵，矩阵加法，矩阵乘法，输出矩阵这些功能。
#include<iostream>
using namespace std;
template<class T>
class matrix //矩阵节点
{
public:
matrix(int theRows = 0, int theColumns = 0);
matrix(const matrix<T>&);
~matrix() { delete[] element; };
int rows()const { return theRows; };
int cols()const { return theColumns; };
T& operator()(int i, int j)const;
matrix<T>& operator=(const matrix<T>&);
matrix<T> operator+()const;
matrix<T> operator+(const matrix<T>&)const;
matrix<T> operator-()const;
matrix<T> operator-(const matrix<T>&)const;
matrix<T> operator*(const matrix<T>&)const;
matrix<T>& operator+=(const T&);
void Input();
void Output();
private:
int theRows;
int theColumns;
T* element; //元素
};
template<class T>
matrix<T>::matrix(int theRows, int theColumns)
{
if (theColumns < 0 || theRows < 0)
{
cout<<"Rows and Cols must be >= 0 ";
}
if ((theColumns == 0 || theRows == 0) && (theColumns != 0 || theRows != 0))
{
cout<<"Either both or neither rows and columns should be zero ";
}
this->theColumns = theColumns;
this->theRows = theRows;
element = new T[theColumns * theRows];
}
template<class T>
matrix<T>::matrix(const matrix<T>& m)
{
theColumns = m.theColumns;
theRows = m.theRows;
size_t number = theColumns * theRows;
element = new T[number];
copy(m.element, m.element + number, element);
}
template<class T>
matrix<T>& matrix<T>::operator=(const matrix<T>& m)
{
if (this != &m)
{
delete[] element;
theColumns = m.theColumns;
theRows = m.theRows;
size_t number = theColumns * theRows;
element = new T[number];
copy(m.element, m.element + number, element);
}
return *this;
}
template<class T>
T& matrix<T>::operator()(int i, int j) const
{
if (i<1 || i>theRows || j<1 || j>theColumns)
{
cout<<"Matrix Index Out Of Bounds ";
}
return element[(i - 1)*theColumns + j - 1];
}
//矩阵相加
template<class T>
matrix<T> matrix<T>::operator+(const matrix<T>& m)const
{
if (theRows != m.theRows || theColumns != m.theColumns)
{
cout<< "Matrix Size is Out of batch ";
}
matrix<T> w(theRows, theColumns);
size_t number = theColumns*theRows;
for (int i = 0; i < number; i++)
{
w.element[i] = element[i] + m.element[i];
}
return w;
}
//矩阵相乘
template<class T>
matrix<T> matrix<T>::operator*(const matrix<T>& m)const
{
if (theColumns != m.theRows || theRows != m.theColumns)
{
cout<<"Matrix Style is Out of batch ";
}
matrix<T> w(theRows, theColumns);
int ct = 0;
int cm = 0;
int cw = 0;
for (int i = 1; i <= theRows; i++)
{
for (int j = 1; j <= theColumns; j++)
{
T sum = element[ct] * m.element[cm];
for (int k = 2; k <= theColumns; k++)
{
ct++;
cm += m.theColumns;
sum += element[ct] * m.element[cm];
}
w.element[cw++] = sum;
ct -= theColumns - 1;
cm = j;
}
ct += theColumns;
cm = 0;
}
return w;
}
//输入矩阵
template<class T>
void matrix<T>::Input()
{
size_t number = theColumns * theRows;
for (int i = 0; i < number; i++)
{
cin >> element[i];
}
cout << "Input fanished" << endl;
return;
}
//输出矩阵
template<class T>
void matrix<T>::Output()
{
size_t number = theColumns * theRows;
for (int i = 0; i < theRows; i++)
{
for (int j = 0; j < theColumns; j++)
{
cout << element[i*theColumns + j] << " ";
}
cout << endl;
}
cout << "Output finished " << endl;
return;
}
int main()
{
matrix<int> a(3, 3);
matrix<int> b(3, 3);
matrix<int> c(3, 3);
matrix<int> d(3, 3);
a.Input();
b.Input();
c= a * b;
d=a+b;
c.Output();
d.Output();
return 0;
}
