area.lineY1() Returns a new line generator that has this area generator’s current defined accessor, curve and context. The line’s x-accessor is this area’s x0-accessor, and the line’s y-accessor is this area’s y1-accessor.

diagram.links() Returns the Delaunay triangulation of the specified data array as an array of links, one for each edge in the mesh. Each link has the following attributes: source - the source node, an element in data. target - the target node, an element in data. Since the triangulation is computed as the dual of the Voronoi diagram, and the Voronoi diagram is clipped by the extent, a subset of the Delaunay links is returned.

dispatch.on(typenames[, callback]) Adds, removes or gets the callback for the specified typenames. If a callback function is specified, it is registered for the specified (fully-qualified) typenames. If a callback was already registered for the given typenames, the existing callback is removed before the new callback is added. The specified typenames is a string, such as start or end.foo. The type may be optionally followed by a period (.) and a name; the optional name allows multiple callba

path.bounds(object) Returns the projected planar bounding box (typically in pixels) for the specified GeoJSON object. The bounding box is represented by a two-dimensional array: [[x₀, y₀], [x₁, y₁]], where x₀ is the minimum x-coordinate, y₀ is the minimum y-coordinate, x₁ is maximum x-coordinate, and y₁ is the maximum y-coordinate. This is handy for, say, zooming in to a particular feature. (Note that in projected planar coordinates, the minimum latitude is typically the maximum y-value, and

d3.interpolateZoom(a, b) Returns an interpolator between the two views a and b of a two-dimensional plane, based on “Smooth and efficient zooming and panning” by Jarke J. van Wijk and Wim A.A. Nuij. Each view is defined as an array of three numbers: cx, cy and width. The first two coordinates cx, cy represent the center of the viewport; the last coordinate width represents the size of the viewport. The returned interpolator exposes a duration property which encodes the recommended transition

d3.geoWagner6() d3.geoWagner6Raw The Wagner VI projection.

area.x0([x]) If x is specified, sets the x0 accessor to the specified function or number and returns this area generator. If x is not specified, returns the current x0 accessor, which defaults to: function x(d) { return d[0]; } When an area is generated, the x0 accessor will be invoked for each defined element in the input data array, being passed the element d, the index i, and the array data as three arguments. The default x0 accessor assumes that the input data are two-element arrays of

area.y1([y]) If y is specified, sets the y1 accessor to the specified function or number and returns this area generator. If y is not specified, returns the current y1 accessor, which defaults to: function y(d) { return d[1]; } A null accessor is also allowed, indicating that the previously-computed y0 value should be reused for the y1 value. When an area is generated, the y1 accessor will be invoked for each defined element in the input data array, being passed the element d, the index i,

d3.precisionRound(step, max) Returns a suggested decimal precision for format types that round to significant digits given the specified numeric step and max values. The step represents the minimum absolute difference between values that will be formatted, and the max represents the largest absolute value that will be formatted. (This assumes that the values to be formatted are also multiples of step.) For example, given the numbers 0.99, 1.0, and 1.01, the step should be 0.01, the max should

d3.geoBounds(feature) Returns the spherical bounding box for the specified GeoJSON feature. The bounding box is represented by a two-dimensional array: [[left, bottom], [right, top]], where left is the minimum longitude, bottom is the minimum latitude, right is maximum longitude, and top is the maximum latitude. All coordinates are given in degrees. (Note that in projected planar coordinates, the minimum latitude is typically the maximum y-value, and the maximum latitude is typically the mini