# VB calculates the circle at three points and returns the outer circle at multiple points.

Source: Internet
Author: User
```'The Runtime is about 5-7 seconds. 'Was previously written when the VB edition replied to a question.

VBScript code

Option explicit private type mypoint x As Double Y as double end type dim P (0 to 49) as mypoint dim smallcx as double dim smallcy as double dim smallr as double private sub form_load () 'set smallr to a very large smallr = 1E + 90 end sub private function equ (byval A as double, byval B as double) as Boolean If ABS (a-B) <0.000001 then equ = true else equ = false end if end function private function is_three_point_in_a_line (byval X1 as double, byval Y1 as double, byval X2 as double, byval Y2 as double, byval X3 as double, byval Y3 as double) as Boolean dim A as double, B as double, e as double A = (X1 + x2) * (x1-X2) + (Y1 + y2) * (Y1-Y2) B = (X3 + x2) * (X3-X2) + (Y3 + y2) * (Y3-Y2) E = (x1-X2) * (Y3-Y2)-(x2-X3) * (Y2-Y1) is_three_point_in_a_line = equ (E, 0) end function private sub calc_tpc (byval X1 as double, byval Y1 as double, byval X2 as double, byval Y2 as double, byval X3 as double, byval Y3 as double, CX as double, cy as double, R as double) dim A as double, B as double, e as double A = (X1 + x2) * (x1-X2) + (Y1 + y2) * (Y1-Y2) B = (X3 + x2) * (X3-X2) + (Y3 + y2) * (Y3-Y2) E = (x1-X2) * (Y3-Y2)-(x2-X3) * (Y2-Y1) Cx = (A * (Y3-Y2) + B * (Y2-Y1 )) /(2 * E) Cy = (A * (x2-X3) + B * (x1-X2)/(2 * E) r = sqr (x1-cx) * (x1-cx) + (Y1-cy) * (Y1-cy) end sub private function incircle (byval CX as double, byval Cy as double, byval R as double, byval PX as double, byval py as double) as Boolean dim L1 as double, l2 as double L1 = PX-cx L2 = Py-Cy if sqr (L1 * l1 + l2 * l2) <= r then incircle = true else incircle = false end if end function private sub commandelist click () CLS randomize timer dim I as long, J as long, K as long dim L as long dim CX as double, Cy as double, R as double dim count as long 'is 50 points, and displayed on the screen for I = 0 to 49 p (I ). X = RND * 2000 p (I ). y = RND * 2000 me. circle (P (I ). x, P (I ). y), 15, vbred next I 'calculates all circles for I = 0 to 49 for J = 0 to 49 for k = 0 to 49 if not is_three_point_in_a_line (P (I ). x, P (I ). y, P (j ). x, P (j ). y, P (k ). x, P (k ). y) then' three points can be used to calculate the circle calc_tpc P (I ). x, P (I ). y, P (j ). x, P (j ). y, P (k ). x, P (k ). y, CX, Cy, R' calculates whether all points are in the circle COUNT = 0 for L = 0 to 49 If incircle (CX, Cy, R, P (l ). x, P (l ). y) then count = count + 1 end if next l if Count = 50 then' all vertices in the circle if r <smallr then smallcx = Cx smallcy = Cy smallr = r end if end if next K next J next I 'draws the smallest circle (smallcx, smallcy), smallr, vbgreen end sub

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