@antv/f2
Version:
Charts for mobile visualization.
60 lines • 1.56 kB
JavaScript
import { prettyNumber } from './pretty-number';
export default function pretty(min, max, m) {
if (m === void 0) {
m = 5;
}
if (min === max) {
return {
max: max,
min: min,
ticks: [min]
};
}
var n = m < 0 ? 0 : Math.round(m);
if (n === 0) return {
max: max,
min: min,
ticks: []
};
/*
R pretty:
https://svn.r-project.org/R/trunk/src/appl/pretty.c
https://www.rdocumentation.org/packages/base/versions/3.5.2/topics/pretty
*/
var h = 1.5; // high.u.bias
var h5 = 0.5 + 1.5 * h; // u5.bias
// 反正我也不会调参，跳过所有判断步骤
var d = max - min;
var c = d / n;
// 当d非常小的时候触发，但似乎没什么用
// const min_n = Math.floor(n / 3);
// const shrink_sml = Math.pow(2, 5);
// if (Math.log10(d) < -2) {
// c = (_.max([ Math.abs(max), Math.abs(min) ]) * shrink_sml) / min_n;
// }
var base = Math.pow(10, Math.floor(Math.log10(c)));
var unit = base;
if (2 * base - c < h * (c - unit)) {
unit = 2 * base;
if (5 * base - c < h5 * (c - unit)) {
unit = 5 * base;
if (10 * base - c < h * (c - unit)) {
unit = 10 * base;
}
}
}
var nu = Math.ceil(max / unit);
var ns = Math.floor(min / unit);
var hi = Math.max(nu * unit, max);
var lo = Math.min(ns * unit, min);
var size = Math.floor((hi - lo) / unit) + 1;
var ticks = new Array(size);
for (var i = 0; i < size; i++) {
ticks[i] = prettyNumber(lo + i * unit);
}
return {
min: lo,
max: hi,
ticks: ticks
};
}