d3.zoom() Creates a new zoom behavior. The returned behavior, zoom

zoom.filter([filter]) If filter is specified, sets the filter to the specified function and returns the zoom

transform.toString() Returns a string representing the

zoom.scaleExtent([extent]) If extent is specified, sets the scale extent to the specified array of numbers

zoom.translateBy(selection, x, y) If selection is a selection,

zoom.duration([duration]) If duration is specified, sets the duration for zoom transitions on double-click

transform.translate(x, y) Returns a transform whose translation tx1 and ty1

d3.zoomIdentity The identity transform, where k = 1, tx = ty = 0.

transform.apply(point) Returns the transformation of the specified point which is a two-element array of numbers

zoom(selection) Applies this zoom behavior to the specified selection