COnvert negative Point values to Positive Point Values

[tomazi]

Hello People I am trying to convert negative point values to positive point values.......I know i can use abs but from what i have read and looked at abs works with int's where I am working with Point's (x,y) data type, Is it possible to apply abs to point data types somehow....?

Here is the code I have written:

	vector<Point> RightTracking;
	vector<Point> LeftTracking;

	vector<Point> Rightsummary;
	vector<Point> Leftsummary;
	
	

	if(Rightarm.size() > 10)
    {
        int i = 0;
        for(vector<Point>::iterator Right_iter = Rightarm.begin(); Right_iter != Rightarm.end(); ++Right_iter, i++)
        {
            if(i % 2)
            {
                RightTracking.push_back(*Right_iter);
            }
        }
    }

    if(RightTracking.size() > 1)
    {
        for(vector<Point>::iterator RRresult_Iter = RightTracking.begin() + 1; RRresult_Iter != RightTracking.end(); ++RRresult_Iter)
        {
            Rightsummary.push_back(*RRresult_Iter - *(RRresult_Iter -1));
		}
    }

	cout<<"MODULO:" <<Rightsummary<<endl;


	if(Leftarm.size() > 10)
    {
        int i = 0;
        for(vector<Point>::iterator Left_iter = Leftarm.begin(); Left_iter != Leftarm.end(); ++Left_iter, i++)
        {
            if(i % 2)
            {
                LeftTracking.push_back(*Left_iter);
            }
        }
    }

    if(LeftTracking.size() > 1)
    {
        for(vector<Point>::iterator LRresult_Iter = LeftTracking.begin() + 1; LRresult_Iter != LeftTracking.end(); ++LRresult_Iter)
        {
            Leftsummary.push_back(*LRresult_Iter - *(LRresult_Iter -1));
			
        }
    }

I was thinking of writing it like this Rightsummary.push_back(abs(*RRresult_Iter) - abs(*(RRresult_Iter -1)));

But it doesnt work like this I get a compile error....


c:\opencv243\build\include\opencv2\core\mat.hpp(1405): or 'cv::MatExpr cv::abs(const cv::Mat &)'
1> c:\opencv243\build\include\opencv2\core\mat.hpp(1406): or 'cv::MatExpr cv::abs(const cv::MatExpr &)'
1> while trying to match the argument list '(cv::Point_<_Tp>)'
1> with
1> [
1> _Tp=int
1> ]
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

Ps....I am using Microsoft Visual C++

[Marcos Modenesi]

I'm not reading your whole example... I just will try to answer your question from the top:

Why don't you write your own abs function:

double my_abs(double num) 
   // only if num is negative ----- example: -10.5
   if (num < 0) {
      num = 0 - num;    //  num = 0 - (-10.5) = 0 + 10.5 = 10.5
   }
   return num;