Mat img(, , CV_8UC1, Scalar());

     std::vector<Point2f> points;

     points.push_back(Point2f(10.5, 10.2));

     points.push_back(Point2f(20.6, 20.7));

     points.push_back(Point2f(33.5, 30.2));

     points.push_back(Point2f(40.7, ));

     //储存拟合直线的容器

     Vec4f line;

     //直线拟合函数

     fitLine(Mat(points), line, CV_DIST_L1, , 0.01, 0.01);

     std::cout << "line: (" << line[] << "," << line[] << ")(" << line[] << "," << line[] << ")\n";

     for (auto i = ; i < points.size(); i++)

         cv::circle(img, cvPoint(points.at(i).x, points.at(i).y), , Scalar());

     double k = line[] / line[];

     double step = ;

     cv::line(img, cvPoint(line[] - step, line[] - k*step), cvPoint(line[] + step, k*step + line[]), Scalar());

     imshow("img", img);

     waitKey();