@visx/vendor
Version:
vendored packages for visx
53 lines (52 loc) • 1.85 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = ticks;
exports.tickIncrement = tickIncrement;
exports.tickStep = tickStep;
var e10 = Math.sqrt(50),
e5 = Math.sqrt(10),
e2 = Math.sqrt(2);
function ticks(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) {
let r0 = Math.round(start / step),
r1 = Math.round(stop / step);
if (r0 * step < start) ++r0;
if (r1 * step > stop) --r1;
ticks = new Array(n = r1 - r0 + 1);
while (++i < n) ticks[i] = (r0 + i) * step;
} else {
step = -step;
let r0 = Math.round(start * step),
r1 = Math.round(stop * step);
if (r0 / step < start) ++r0;
if (r1 / step > stop) --r1;
ticks = new Array(n = r1 - r0 + 1);
while (++i < n) ticks[i] = (r0 + i) / step;
}
if (reverse) ticks.reverse();
return ticks;
}
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);
}
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;
}