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