In the Train Tamping / socadeiras (machines that correct alignment of the tracks) using the method of ropes and to align the arrow via either curved or straight.
Each type of machine has its rope, just different lengths between them and as well as the arrow reading is also different in each type of machine.

But the problem is:
There are some software of these machines that give the project arrow and the arrow reading this arrow representing a value of each string of each type of machine being difficult to understand that value which may be the Lightning or 20m rope arrow ...

So this algorithm is that the arrow machine translation with the radius and thus a better comprehension and understanding of the work that is taking place and even check the machine with the project radius.

Essentially there are two sofwares the Iberian Peninsula and the WinAlc CGV (discontinued).
The CGV uses the arrows of machines.


There is a module for calculations of the arrows 20 and 10m and get the radius and vice versa.