Strange results of optimal transportation curve reconstruction

[stla]

Hello,

I've just started to play with the optimal transportation curve reconstruction.

I take some random points on the square +/-1 x +/-1. I use otr.run(100), and sometimes I get such segments in the output:

     x1 y1 x2 y2
[1,] -2 -2 -2  2
[2,]  2 -2  2  2
[3,]  2  2 -2  2
[4,] -2  2  2 -2

Do you have an idea of the reason?

[stla]

I've made a reprex here: https://gist.github.com/stla/d4462b548e50a3b966a7b13e78c9e413.

[stla]

I close since I transferred to an issue.