The routine returns the name of the center of the given circle, ellipse or hyperbola c

The center cn of an ellipse or a hyperbola c is the midpoint of the line segment joining the foci.

If the first optional argument cn is given, the name of the center c becomes cn

Use coordinates or detail for more details on the center.

The command with(geometry,center) allows the use of the abbreviated form of this command.

$\mathrm{with}\left(\mathrm{geometry}\right)\:$

$\mathrm{\_EnvHorizontalName}≔x\:$$\mathrm{\_EnvVerticalName}≔y\:$

$\mathrm{circle}\left(c\,{\left(x-3\right)}^2+{\left(y-1\right)}^2=4\right)$

$c$

$\mathrm{center}\left(c\right)$

$\mathrm{center\_c}$

$\mathrm{coordinates}\left(\mathrm{center}\left(o\,c\right)\right)$

$\left[3\,1\right]$

$\mathrm{center}\left(c\right)$

$o$

$\mathrm{detail}\left(c\right)$

$\begin{array}{ll}\text{name of the object}& c\\ \text{form of the object}& \mathrm{circle2d}\\ \text{name of the center}& o\\ \text{coordinates of the center}& \left[3\,1\right]\\ \text{radius of the circle}& \sqrt{4}\\ \text{equation of the circle}& x^2+y^2-6x-2y+6=0\end{array}$