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{\bf  NURBS}  \hfill \today
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{\bf G. Farin }
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\begin {center} {\bf Programming  assignment \#2 }\\
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{\em due 3-13}\\
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Write a routine which converts a conic in implicit form:
$$
	a_1x^2 + a_2 y^2 + a_3 xy + a_4 x + a_5 y + a_6 = 0
$$
into rational quadratic form when its endpoints ${\bf b}_0$
and ${\bf b}_2$ are known.

Experiment with the conic $xy-4=0$ and
$$
	{\bf b}_0=\begin{bmatrix}4 \\ 1
		  \end{bmatrix},~~
	{\bf b}_2=\begin{bmatrix}2 \\ 2
		  \end{bmatrix}.
$$
What is $z_1$?
Then work with  ten circles from the family of circles passing through
$$
	{\bf b}_0=\begin{bmatrix}-1 \\ 0
		  \end{bmatrix},~~
	{\bf b}_2=\begin{bmatrix}1 \\ 0
		  \end{bmatrix}.
$$
Also record their middle weights.

Hand in: plots, with the weights annotated.




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