src/scales/scale.time.js
function determineUnitForAutoTicks(minUnit, min, max, capacity) {
	var ilen = UNITS.length;
	var i, interval, factor;

	for (i = UNITS.indexOf(minUnit); i < ilen - 1; ++i) {
		interval = INTERVALS[UNITS[i]];
		factor = interval.steps ? interval.steps[interval.steps.length - 1] : MAX_INTEGER;

		if (interval.common && Math.ceil((max - min) / (factor * interval.size)) <= capacity) {
			return UNITS[i];
		}
	}

	return UNITS[ilen - 1];
}
function determineUnitForAutoTicks(minUnit, min, max, capacity) {
	var ilen = UNITS.length;
	var i, interval, factor;

	for (i = UNITS.indexOf(minUnit); i < ilen - 1; ++i) {
		interval = INTERVALS[UNITS[i]];
		factor = interval.steps ? interval.steps[interval.steps.length - 1] : MAX_INTEGER;

		if (interval.common && Math.ceil((max - min) / (factor * interval.size)) <= capacity) {
			return UNITS[i];
		}
	}

	return UNITS[ilen - 1];
}
function determineUnitForAutoTicks ( minUnit , min , max , capacity ) { var ilen = UNITS . length ; var i , interval , factor ; for ( i = UNITS . indexOf ( minUnit ) ; i < ilen - 1 ; ++ i ) { interval = INTERVALS [ UNITS [ i ] ] ; factor = interval . steps ? interval . steps [ interval . steps . length - 1 ] : MAX_INTEGER ; if ( interval . common && Math . ceil ( ( max - min ) / ( factor * interval . size ) ) <= capacity ) { return UNITS [ i ] ; } } return UNITS [ ilen - 1 ] ; }
Figures out what unit results in an appropriate number of auto-generated ticks
Figures out what unit results in an appropriate number of auto - generated ticks