d3.packEnclose()

d3.packEnclose(circles)

Computes the smallest circle that encloses the specified array of circles, each of which must have a circle.r property specifying the circle’s radius, and circle.x and circle.y properties specifying the circle’s center. The enclosing circle is computed using Welzl’s algorithm adapted to enclose circles rather than points. (See also Apollonius’ Problem.)