d3.curveCatmullRomOpen(context) Produces a cubic Catmull–Rom spline using the specified control points and the parameter alpha, which defaults to 0.5, as proposed by Yuksel et al. Unlike curveCatmullRom, one-sided differences are not used for the first and last piece, and thus the curve starts at the second point and ends at the penultimate point.

pack.radius([radius]) If radius is specified, sets the pack layout’s radius accessor to the specified function and returns this pack layout. If radius is not specified, returns the current radius accessor, which defaults to null. If the radius accessor is null, the radius of each leaf circle is derived from the leaf node.value (computed by node.sum); the radii are then scaled proportionally to fit the layout size. If the radius accessor is not null, the radius of each leaf circle is specifie

collide.radius([radius]) If radius is specified, sets the radius accessor to the specified number or function, re-evaluates the radius accessor for each node, and returns this force. If radius is not specified, returns the current radius accessor, which defaults to: function radius() { return 1; } The radius accessor is invoked for each node in the simulation, being passed the node and its zero-based index. The resulting number is then stored internally, such that the radius of each node i

d3.interpolateGnBu(t) d3.schemeGnBu Given a number t in the range [0,1], returns the corresponding color from the “GnBu” sequential color scheme represented as an RGB string.

area.curve([curve]) If curve is specified, sets the curve factory and returns this area generator. If curve is not specified, returns the current curve factory, which defaults to curveLinear.

request.response(value) Sets the response value function to the specified function and returns this request instance. The response value function is used to map the response XMLHttpRequest object to a useful data value. See the convenience methods json and text for examples.

zoom.interpolate([interpolate]) If interpolate is specified, sets the interpolation factory for zoom transitions to the specified function. If interpolate is not specified, returns the current interpolation factory, which defaults to d3.interpolateZoom to implement smooth zooming. To apply direct interpolation between two views, try d3.interpolate instead.

voronoi(data) Computes the Voronoi diagram for the specified data points.

d3.interpolateOrRd(t) d3.schemeOrRd Given a number t in the range [0,1], returns the corresponding color from the “OrRd” sequential color scheme represented as an RGB string.

radialArea.innerRadius([radius]) Equivalent to area.y0, except the accessor returns the radius: the distance from the origin ⟨0,0⟩.