matrix.java

基本的数据结构的java代码

public class Matrix{
	private MyVector values;			//成员变量，矩阵元素
	private int h;						//成员变量，矩阵行数		
	private int w; 						//成员变量，矩阵列数

	public Matrix(int h,int w){			//构造函数，h为行数，w为列数
		if(!(h > 0 && w > 0))
			throw new ArrayIndexOutOfBoundsException("h or w  < " + 1);
		values = new MyVector(h);				//创建有h行的对象
		for(int i = 0; i < h; i++){
			MyVector row = new MyVector(w); 	//创建有w列的对象
			values.add(row);					//让行元素引用等于row
			for(int j = 0; j < w; j++){
				row.add(null);					//初始化矩阵元素为null
			}
		}
		this.h = h;
		this.w = w;
	}
	
	public void set(int row,int col,Object value){		//置元素
		if(!(row >= 0 && w >= 0 && row < h && col <w))
			throw new ArrayIndexOutOfBoundsException("h or w  < " + "-1");
		MyVector selrow = (MyVector)values.get(row);
		selrow.set(col,value); 
	}
	
	public Object get(int row,int col){					//取元素
		if(!(row >= 0 && w >= 0 && row < h && col <w))
			throw new ArrayIndexOutOfBoundsException("h or w  < " + "-1");
		MyVector selrow = (MyVector)values.get(row);
		return selrow.get(col); 
	}
	
	public int width(){									//矩阵列数
		return w;
	}
	
	public int height(){								//矩阵行数
		return h;
	}
	
	public Matrix add(Matrix b){		//矩阵加
		if(height() != b.height() || width()!= b.width()){
			throw new ArrayIndexOutOfBoundsException("Matrix h and w error");
		}
		
		Matrix result = new Matrix(height(),width());
		
		for(int i = 0;i < height();i ++){
			for(int j = 0;j < width(); j ++){
				Integer i1 = (Integer)get(i,j);
				Integer i2 = (Integer)(b.get(i,j));				
				result.set(i,j,new Integer(i1.intValue()+i2.intValue()));
			}
		}
		
		return result;
	}
	
	public void print(){							//输出矩阵元素
		for(int i = 0; i < h; i++){
			for(int j = 0; j < w; j++){
				System.out.print(get(i,j)+" ");//(get(i,j)返回Object，不需要调用toString()函数？？
			}
			System.out.println();
		}
	}	
}