can you elaborate one part of the code?

[mrgransky]

Hi,

could you please explain this part of the code?

if((scale>0.1) 	&& (t.at<double>(2) > t.at<double>(0)) 
					&& (t.at<double>(2) > t.at<double>(1))) 
	{
		t_f = t_f + scale*(R_f*t);
		R_f = R*R_f;
	}
	else 
	{
		cout << "scale below 0.1, or incorrect translation" << endl;
	}

when I apply this code to my own dataset, I get unreasonable results.
Is there any theoretical logic written in any textbooks you might know about rotation and translation concatenation to build the trajectory?
Cheers,