Curve that touches three points: Difference between revisions

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m (→‎{{header|Perl}}: don't need the off-site image any longer)
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[100, 200.000000]
[100, 200.000000]
[200, 10.000000]</pre>
[200, 10.000000]</pre>

=={{header|FreeBASIC}}==
{{trans|Ada}}
<syntaxhighlight lang="vb">' Point P1
Dim As Double X1 = 10.0
Dim As Double Y1 = 10.0

' Point P2
Dim As Double X2 = 100.0
Dim As Double Y2 = 200.0

' Point P3
Dim As Double X3 = 200.0
Dim As Double Y3 = 10.0

' Point P4 - midpoint between P1 and P2
Dim As Double X4 = (X1 + X2) / 2.0
Dim As Double Y4 = (Y1 + Y2) / 2.0
Dim As Double S4 = (Y2 - Y1) / (X2 - X1) ' Slope P1-P2
Dim As Double A4 = -1.0 / S4 ' Slope P4-Center
' Y4 = A4 * X4 + B4 <=> B4 = Y4 - A4 * X4
Dim As Double B4 = Y4 - A4 * X4

' Point P5 - midpoint between P2 and P3
Dim As Double X5 = (X2 + X3) / 2.0
Dim As Double Y5 = (Y2 + Y3) / 2.0
Dim As Double S5 = (Y3 - Y2) / (X3 - X2) ' Slope P2-P3
Dim As Double A5 = -1.0 / S5 ' Slope P5-Center
' Y5 = A5 * X5 + B5 <=> B5 = Y5 - A5 * X5
Dim As Double B5 = Y5 - A5 * X5

' Find center
' Y = A4 * X + B4 ' Line 1
' Y = A5 * X + B5 ' Line 2
' Solve for X:
' A4 * X + B4 = A5 * X + B5
' A4 * X - A5 * X = B5 - B4
' X * (A4 - A5) = B5 - B4
' X = (B5 - B4) / (A4 - A5)
Dim As Double Xc = (B5 - B4) / (A4 - A5)
Dim As Double Yc = A4 * Xc + B4
' Radius
Dim As Double R = Sqr((X1 - Xc) ^ 2 + (Y1 - Yc) ^ 2)

Print Using "Center : (###.#, ###.#)"; Xc; Yc
Print Using "Radius : ###.#"; R

Sleep</syntaxhighlight>


=={{header|Go}}==
=={{header|Go}}==
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