diameter, radius, center, midpoint

[Pierre Abbat <phma@webjockey.net>]

I looked at Recent Changes on jbovlaste and saw {mijgresirji}, which means 
"diameter" in the sense of a line passing through the center of something. 
There are other senses:
Given a set of points, the diameter is the distance between the two farthest 
points, or the line through them. The center is the point such that the 
distance from it to the farthest point is a minimum. A radius is the distance 
from the center to a farthest point, or the line through the center and a 
farthest point.
I use AutoCAD, and I often draw a line from the center of an arc, or its 
midpoint, to some other point. The center of an arc is not as defined above 
(which would be the midpoint of its chord, unless it's more than half a 
circle), but the center of the circle of which it is an arc; the midpoint is 
the point on the arc equidistant from the ends. The center of a line and the 
midpoint of a circle are undefined. How should these distinctions be said in 
Lojban?

phma
-- 
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.icu'u la ma'atman.