echarts
Version:
A powerful charting and visualization library for browser
183 lines (155 loc) • 6.43 kB
JavaScript
/**
* Interval scale
* @module echarts/coord/scale/Time
*/
define(function (require) {
// [About UTC and local time zone]:
// In most cases, `number.parseDate` will treat input data string as local time
// (except time zone is specified in time string). And `format.formateTime` returns
// local time by default. option.useUTC is false by default. This design have
// concidered these common case:
// (1) Time that is persistent in server is in UTC, but it is needed to be diplayed
// in local time by default.
// (2) By default, the input data string (e.g., '2011-01-02') should be displayed
// as its original time, without any time difference.
var zrUtil = require('zrender/core/util');
var numberUtil = require('../util/number');
var formatUtil = require('../util/format');
var scaleHelper = require('./helper');
var IntervalScale = require('./Interval');
var intervalScaleProto = IntervalScale.prototype;
var mathCeil = Math.ceil;
var mathFloor = Math.floor;
var ONE_SECOND = 1000;
var ONE_MINUTE = ONE_SECOND * 60;
var ONE_HOUR = ONE_MINUTE * 60;
var ONE_DAY = ONE_HOUR * 24;
// FIXME 公用？
var bisect = function (a, x, lo, hi) {
while (lo < hi) {
var mid = lo + hi >>> 1;
if (a[mid][2] < x) {
lo = mid + 1;
}
else {
hi = mid;
}
}
return lo;
};
/**
* @alias module:echarts/coord/scale/Time
* @constructor
*/
var TimeScale = IntervalScale.extend({
type: 'time',
/**
* @override
*/
getLabel: function (val) {
var stepLvl = this._stepLvl;
var date = new Date(val);
return formatUtil.formatTime(stepLvl[0], date, this.getSetting('useUTC'));
},
/**
* @override
*/
niceExtent: function (opt) {
var extent = this._extent;
// If extent start and end are same, expand them
if (extent[0] === extent[1]) {
// Expand extent
extent[0] -= ONE_DAY;
extent[1] += ONE_DAY;
}
// If there are no data and extent are [Infinity, -Infinity]
if (extent[1] === -Infinity && extent[0] === Infinity) {
var d = new Date();
extent[1] = new Date(d.getFullYear(), d.getMonth(), d.getDate());
extent[0] = extent[1] - ONE_DAY;
}
this.niceTicks(opt.splitNumber);
// var extent = this._extent;
var interval = this._interval;
if (!opt.fixMin) {
extent[0] = numberUtil.round(mathFloor(extent[0] / interval) * interval);
}
if (!opt.fixMax) {
extent[1] = numberUtil.round(mathCeil(extent[1] / interval) * interval);
}
},
/**
* @override
*/
niceTicks: function (approxTickNum) {
var timezoneOffset = this.getSetting('useUTC')
? 0 : numberUtil.getTimezoneOffset() * 60 * 1000;
approxTickNum = approxTickNum || 10;
var extent = this._extent;
var span = extent[1] - extent[0];
var approxInterval = span / approxTickNum;
var scaleLevelsLen = scaleLevels.length;
var idx = bisect(scaleLevels, approxInterval, 0, scaleLevelsLen);
var level = scaleLevels[Math.min(idx, scaleLevelsLen - 1)];
var interval = level[2];
// Same with interval scale if span is much larger than 1 year
if (level[0] === 'year') {
var yearSpan = span / interval;
// From "Nice Numbers for Graph Labels" of Graphic Gems
// var niceYearSpan = numberUtil.nice(yearSpan, false);
var yearStep = numberUtil.nice(yearSpan / approxTickNum, true);
interval *= yearStep;
}
var niceExtent = [
Math.round(mathCeil((extent[0] - timezoneOffset) / interval) * interval + timezoneOffset),
Math.round(mathFloor((extent[1] - timezoneOffset)/ interval) * interval + timezoneOffset)
];
scaleHelper.fixExtent(niceExtent, extent);
this._stepLvl = level;
// Interval will be used in getTicks
this._interval = interval;
this._niceExtent = niceExtent;
},
parse: function (val) {
// val might be float.
return +numberUtil.parseDate(val);
}
});
zrUtil.each(['contain', 'normalize'], function (methodName) {
TimeScale.prototype[methodName] = function (val) {
return intervalScaleProto[methodName].call(this, this.parse(val));
};
});
// Steps from d3
var scaleLevels = [
// Format step interval
['hh:mm:ss', 1, ONE_SECOND], // 1s
['hh:mm:ss', 5, ONE_SECOND * 5], // 5s
['hh:mm:ss', 10, ONE_SECOND * 10], // 10s
['hh:mm:ss', 15, ONE_SECOND * 15], // 15s
['hh:mm:ss', 30, ONE_SECOND * 30], // 30s
['hh:mm\nMM-dd',1, ONE_MINUTE], // 1m
['hh:mm\nMM-dd',5, ONE_MINUTE * 5], // 5m
['hh:mm\nMM-dd',10, ONE_MINUTE * 10], // 10m
['hh:mm\nMM-dd',15, ONE_MINUTE * 15], // 15m
['hh:mm\nMM-dd',30, ONE_MINUTE * 30], // 30m
['hh:mm\nMM-dd',1, ONE_HOUR], // 1h
['hh:mm\nMM-dd',2, ONE_HOUR * 2], // 2h
['hh:mm\nMM-dd',6, ONE_HOUR * 6], // 6h
['hh:mm\nMM-dd',12, ONE_HOUR * 12], // 12h
['MM-dd\nyyyy', 1, ONE_DAY], // 1d
['week', 7, ONE_DAY * 7], // 7d
['month', 1, ONE_DAY * 31], // 1M
['quarter', 3, ONE_DAY * 380 / 4], // 3M
['half-year', 6, ONE_DAY * 380 / 2], // 6M
['year', 1, ONE_DAY * 380] // 1Y
];
/**
* @param {module:echarts/model/Model}
* @return {module:echarts/scale/Time}
*/
TimeScale.create = function (model) {
return new TimeScale({useUTC: model.ecModel.get('useUTC')});
};
return TimeScale;
});