catmullRom.alpha()

catmullRom.alpha(alpha)

Returns a cubic Catmull–Rom curve with the specified alpha in the range [0, 1]. If alpha is zero, produces a uniform spline, equivalent to curveCardinal with a tension of zero; if alpha is one, produces a chordal spline; if alpha is 0.5, produces a centripetal spline. Centripetal splines are recommended to avoid self-intersections and overshoot. For example:

var line = d3.line().curve(d3.curveCatmullRom.alpha(0.5));