The shape of an ellipse is determined solely by its height and width.
A: ellipse thick line thin color gray left 70% from 2mm left of (A.w,A.n) line same from 2mm left of (A.w,A.s) text "height" at (7/8<previous.start,previous.end>,1/2<1st line,2ndline>) line thin color gray from previous text.n up until even with 1st line -> line thin color gray from previous text.s down until even with 2nd line -> X1: line thin color gray down 50% from 2mm below (A.w,A.s) X2: line thin color gray down 50% from 2mm below (A.e,A.s) text "width" at (1/2<X1,X2>,6/8<X1.start,X1.end>) line thin color gray from previous text.w left until even with X1 -> line thin color gray from previous text.e right until even with X2 ->→ /pikchrshow
Unlike a circle, ellipses have no radius, but if the width and height are equal, it is visually identical to a circle.
Boundary Points
A: ellipse thin dot ".c" below at A dot ".n" above at A.n dot " .ne" ljust above at A.ne dot " .e" ljust at A.e dot " .se" ljust below at A.se dot ".s" below at A.s dot ".sw " rjust below at A.sw dot ".w " rjust at A.w dot ".nw " rjust above at A.nw→ /pikchrshow