X, Y initial sets were defined by nodes of some grid on the image plane.
Density of the grid was chosen so that in any circle in radius R_min/2
one node of this grid hitted even. In the case of a square grid its step
should be less, than R_min/sqrt(2). Remaining parameters were prescribed
identical to all sets. A value of parameter B corresponding to length of
initial contiguous segments was chosen smaller than (R_min/2)*sqrt(3).
This choice is caused by the obtained theoretical estimation for a resolving
power of the suggested approximation method. Parameter D was chosen equal
0.5*B, A - arbitrary, P1 = P2 = 0.