长宽相等的矩阵（二维数组）逆时针旋转90度

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我是靠谱客的博主冷艳路灯，最近开发中收集的这篇文章主要介绍长宽相等的矩阵（二维数组）逆时针旋转90度，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

将长宽相等的矩阵（二维数组）逆时针旋转90度，例如，有如下一个二维数组

00 10 20 30 40 50 60  
01 11 21 31 41 51 61  
02 12 22 32 42 52 62  
03 13 23 33 43 53 63  
04 14 24 34 44 54 64  
05 15 25 35 45 55 65  
06 16 26 36 46 56 66

将其逆时针旋转90度，一种比较快捷的方法是通过两次位置调换即可：

第一步，将矩阵沿着自“左上”到“右下”的对角线对调，可得到如下的对调之后的二维数组：

00 01 02 03 04 05 06  
10 11 12 13 14 15 16  
20 21 22 23 24 25 26  
30 31 32 33 34 35 36  
40 41 42 43 44 45 46  
50 51 52 53 54 55 56  
60 61 62 63 64 65 66

第二步，将矩阵上下行对调，即第一行与倒数第一行对调，第二行与倒数第二行对调，依次类推，可得到如下最终版的二维数组（也即原始二维数组逆时针旋转90度的数组）：

60 61 62 63 64 65 66  
50 51 52 53 54 55 56  
40 41 42 43 44 45 46  
30 31 32 33 34 35 36  
20 21 22 23 24 25 26  
10 11 12 13 14 15 16  
00 01 02 03 04 05 06

相关的java版小测试程序为：

public class Test {
	public static void main(String[] args) {
		String m_TestData[][] = {
				{"00","10","20","30","40","50","60"},
				{"01","11","21","31","41","51","61"},
				{"02","12","22","32","42","52","62"},
				{"03","13","23","33","43","53","63"},
				{"04","14","24","34","44","54","64"},
				{"05","15","25","35","45","55","65"},
				{"06","16","26","36","46","56","66"}
		};
		int iX, iY;
		String tmpData;
		int m_iHeight = 7;
		int m_iWidth = 7;
		System.out.println("原始数据：");
		for(iY=0;iY<m_iHeight; ++iY){
			for(iX=0; iX<m_iWidth; ++iX)
				System.out.print(m_TestData[iY][iX] + " ");
			System.out.println(" ");
		}
		for(iY=0; iY<m_iHeight; ++iY){
			iX= iY;
			for(; iX<m_iWidth; ++iX){
				tmpData = m_TestData[iY][iX];
				m_TestData[iY][iX] = m_TestData[iX][iY];
				m_TestData[iX][iY] = tmpData;
			}
		}	
		System.out.println("对角调换之后的数据：");
		for(iY=0;iY<m_iHeight; ++iY){
			for(iX=0; iX<m_iWidth; ++iX)
				System.out.print(m_TestData[iY][iX] + " ");
			System.out.println(" ");
		}
		for(iY=0; iY<m_iHeight/2; ++iY){
			for(iX=0; iX<m_iWidth; ++iX){
				tmpData = m_TestData[iY][iX];
				m_TestData[iY][iX] = m_TestData[m_iHeight-iY-1][iX];
				m_TestData[m_iHeight-iY-1][iX] = tmpData;
			}	
		}
		System.out.println("上下对调之后的数据：");
		for(iY=0;iY<m_iHeight; ++iY){
			for(iX=0; iX<m_iWidth; ++iX)
				System.out.print(m_TestData[iY][iX] + " ");
			System.out.println(" ");
		}
	}
}