cv::Mat submat = m.colRange(5,10);
m.colRange(3,7).setTo(0);This will set all elements in columns 3 to 6 inclusive to 0, leaving the rest of the matrix unchanged. In both examples, we use the colRange function to select a range of columns from a cv::Mat object. This function takes two parameters: the starting and ending indices of the range, as integers. The function returns a new cv::Mat object that contains only the selected columns. The package library for this function is OpenCV. To use it, you need to include the appropriate header files and link against the OpenCV library.