| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051 |
- var e10 = Math.sqrt(50),
- e5 = Math.sqrt(10),
- e2 = Math.sqrt(2);
- export default function(start, stop, count) {
- var reverse,
- i = -1,
- n,
- ticks,
- step;
- stop = +stop, start = +start, count = +count;
- if (start === stop && count > 0) return [start];
- if (reverse = stop < start) n = start, start = stop, stop = n;
- if ((step = tickIncrement(start, stop, count)) === 0 || !isFinite(step)) return [];
- if (step > 0) {
- start = Math.ceil(start / step);
- stop = Math.floor(stop / step);
- ticks = new Array(n = Math.ceil(stop - start + 1));
- while (++i < n) ticks[i] = (start + i) * step;
- } else {
- start = Math.floor(start * step);
- stop = Math.ceil(stop * step);
- ticks = new Array(n = Math.ceil(start - stop + 1));
- while (++i < n) ticks[i] = (start - i) / step;
- }
- if (reverse) ticks.reverse();
- return ticks;
- }
- export function tickIncrement(start, stop, count) {
- var step = (stop - start) / Math.max(0, count),
- power = Math.floor(Math.log(step) / Math.LN10),
- error = step / Math.pow(10, power);
- return power >= 0
- ? (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1) * Math.pow(10, power)
- : -Math.pow(10, -power) / (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1);
- }
- export function tickStep(start, stop, count) {
- var step0 = Math.abs(stop - start) / Math.max(0, count),
- step1 = Math.pow(10, Math.floor(Math.log(step0) / Math.LN10)),
- error = step0 / step1;
- if (error >= e10) step1 *= 10;
- else if (error >= e5) step1 *= 5;
- else if (error >= e2) step1 *= 2;
- return stop < start ? -step1 : step1;
- }
|