36 lines
848 B
JavaScript
36 lines
848 B
JavaScript
import {linearish} from "./linear.js";
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import {copy, transformer} from "./continuous.js";
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import {initRange} from "./init.js";
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function transformSymlog(c) {
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return function(x) {
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return Math.sign(x) * Math.log1p(Math.abs(x / c));
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};
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}
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function transformSymexp(c) {
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return function(x) {
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return Math.sign(x) * Math.expm1(Math.abs(x)) * c;
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};
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}
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export function symlogish(transform) {
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var c = 1, scale = transform(transformSymlog(c), transformSymexp(c));
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scale.constant = function(_) {
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return arguments.length ? transform(transformSymlog(c = +_), transformSymexp(c)) : c;
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};
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return linearish(scale);
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}
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export default function symlog() {
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var scale = symlogish(transformer());
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scale.copy = function() {
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return copy(scale, symlog()).constant(scale.constant());
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};
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return initRange.apply(scale, arguments);
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}
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