| import {bisect} from "d3-array"; |
| import {linearish} from "./linear.js"; |
| import {initRange} from "./init.js"; |
|
|
| export default function quantize() { |
| var x0 = 0, |
| x1 = 1, |
| n = 1, |
| domain = [0.5], |
| range = [0, 1], |
| unknown; |
|
|
| function scale(x) { |
| return x != null && x <= x ? range[bisect(domain, x, 0, n)] : unknown; |
| } |
|
|
| function rescale() { |
| var i = -1; |
| domain = new Array(n); |
| while (++i < n) domain[i] = ((i + 1) * x1 - (i - n) * x0) / (n + 1); |
| return scale; |
| } |
|
|
| scale.domain = function(_) { |
| return arguments.length ? ([x0, x1] = _, x0 = +x0, x1 = +x1, rescale()) : [x0, x1]; |
| }; |
|
|
| scale.range = function(_) { |
| return arguments.length ? (n = (range = Array.from(_)).length - 1, rescale()) : range.slice(); |
| }; |
|
|
| scale.invertExtent = function(y) { |
| var i = range.indexOf(y); |
| return i < 0 ? [NaN, NaN] |
| : i < 1 ? [x0, domain[0]] |
| : i >= n ? [domain[n - 1], x1] |
| : [domain[i - 1], domain[i]]; |
| }; |
|
|
| scale.unknown = function(_) { |
| return arguments.length ? (unknown = _, scale) : scale; |
| }; |
|
|
| scale.thresholds = function() { |
| return domain.slice(); |
| }; |
|
|
| scale.copy = function() { |
| return quantize() |
| .domain([x0, x1]) |
| .range(range) |
| .unknown(unknown); |
| }; |
|
|
| return initRange.apply(linearish(scale), arguments); |
| } |
|
|
