Perform the angle between two points and the x-axis.
[A] = NL_V_Polar(X1,Y1,X2,Y2)
X-coordinate of the first point.
Y-coordinate of the first point.
X-coordinate of the second point.
Y-coordinate of the second point.
Angle.
NL_V_Polar performs the angle A between the two points N1 (X1,Y1), N2 (X2,Y2) and the x-axis.