Eigen库学习笔记（十五）Eigen获取最小值与最小值索引

Eigen库学习笔记（十五）Eigen获取最小值与最小值索引

准备编写NMS时，需要获取当前行最大值，下面用一段代码测试了类似功能。

#include<Eigen/Core>
#include<iostream>
using namespace std;
using namespace Eigen;

int main()
{
	
	MatrixXd::Index maxRow, maxCol;
	MatrixXd::Index minRow, minCol;
	MatrixXd mMat(4,4);
	mMat << 11, 10, 13, 15,
	3, 24, 56,	1,
	2, 12, 45,	0,
	8, 5,	6,	4;
	double min = mMat.minCoeff(&minRow,&minCol);
	double max = mMat.maxCoeff(&maxRow,&maxCol);
	cout << "Max = \n" << max << endl;
	cout << "Min = \n" << min << endl;
	cout << "minRow = " << minRow << "minCol = " <<minCol<<endl;
	cout << "maxRow = " << maxRow << "maxCol = " << maxCol << endl;
	
	Eigen::VectorXd v(4);
	Eigen::VectorXd::Index col;
	for(int i=0;i<=3;i++){
		//TODO
		v = mMat.row(i);
		cout << "v = " << v <<endl;
		double minv = v.minCoeff(&col);
		cout << " min v = " << minv <<endl;
		cout << "min v index = " << col <<endl;
	}
	
	
	return 0;
}

运行结果

Max =
56
Min =
0
minRow = 2minCol = 3
maxRow = 1maxCol = 2
v = 11
10
13
15
 min v = 10
min v index = 1
v =  3
24
56
 1
 min v = 1
min v index = 3
v =  2
12
45
 0
 min v = 0
min v index = 3
v = 8
5
6
4
 min v = 4
min v index = 3

--------------------------------
Process exited after 0.02429 seconds with return value 0

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