
(distance (list 1 1 0) (list 2 2 0)) returns 1.41421
(distance (list 0 0 0) (list 2 2 8)) returns 8.48528
After (setq p1 (list 4.1 2.2) p2 (list 7.1 2.2))
(distance p1 p2) returns 3.0
(angle (list 2.0 2.0) (list 3.0 3.0)) returns 0.785398
After (setq p1 (list 6.0 2.0) p2 (list 3.0 2.0))
(angle p1 p2) returns 3.14159
(polar (list 2 2) 2.356195 6.0) returns the coordinates of the
point that is 6 units at angle 2.356195 radians from 2,2
After (setq p1 (list 8 1 0) a (/ pi 3) d 2.5)
(polar p1 a d) returns the coordinates of the point that is 2.5
units at angle 60 degrees (/ pi 3) from 8,1,0
If the base point is a 2D point (no Z coordinate given), then a 2D point
is returned. If the base point is a 3D point, then the returned point
will have the same Z coordinate as the base point. The angle is always
measured in the XY construction plane of the current UCS.
(inters '(1 1) '(2 2) '(1 2) '(2 1) T) returns (1.5 1.5), which are the coordinates of a point at the intersection of the line joining 1,1 and 2,2 and the line joining 1,2 and 2,1
The fifth argument ("T") is optional. If it is omitted or if it is T (or any nonnil expression) the intersection point must lie on both lines. If it is nil, the intersection point can be off the end of one or both lines.
After (setq p '(0 0) q '(9 9) r '(6 0) s '(5 1))
(inters p q r s) returns nil
(inters p q r s T) returns nil
(inters p q r s nil) returns (3.0 3.0)
(inters (list 2 2 2) (list 2 0 4) (list 2 4 2) (list 2 6 4) nil)
returns (2.0 3.0 1.0)
(inters (list 2 2 2) (list 2 0 4) (list 2 4 2) (list 1 6 4) nil)
returns nil because the lines do not lie in the same plane
Remember that all points in variables are interpreted in the current
UCS even if they were established in a different UCS. Use the trans function
to translate points from one UCS to another. See trans
under "14  Working with AutoCAD."
(sin 0.5) returns 0.479425
(sin (* pi 0.25)) returns 0.707106
(sin (* pi 1.25)) returns 0.707106
(cos 0.5) returns 0.877583
(cos (* pi 0.25)) returns 0.707107
(cos (* pi 0.75)) returns 0.707107
(atan 1.0) returns 0.785398
(atan 0.5) returns 0.463648
(atan 7.5 2.5) returns 1.24905 (the arc whose tangent is 7.5
divided by 2.5)
If one argument is used, the range of angles returned is from pi/2
to +pi/2 radians and the sign of the angle is the same as the sign of the
argument. If two arguments are used the range of angles returned
is from pi to + pi radians and the sign of the angle is the same as the
sign of the first argument.