src/scale/Interval.ts - echarts - Git at Google

 /*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */


 import * as numberUtil from '../util/number';
 import * as formatUtil from '../util/format';
 import Scale from './Scale';
 import * as helper from './helper';
 import {ScaleTick, Dictionary} from '../util/types';

 const roundNumber = numberUtil.round;

 class IntervalScale<SETTING extends Dictionary<unknown> = Dictionary<unknown>> extends Scale<SETTING> {

     static type = 'interval';
     type = 'interval';

     // Step is calculated in adjustExtent.
     protected _interval: number = 0;
     protected _niceExtent: [number, number];
     private _intervalPrecision: number = 2;


     parse(val: number): number {
         return val;
     }

     contain(val: number): boolean {
         return helper.contain(val, this._extent);
     }

     normalize(val: number): number {
         return helper.normalize(val, this._extent);
     }

     scale(val: number): number {
         return helper.scale(val, this._extent);
     }

     setExtent(start: number | string, end: number | string): void {
         const thisExtent = this._extent;
         // start,end may be a Number like '25',so...
         if (!isNaN(start as any)) {
             thisExtent[0] = parseFloat(start as any);
         }
         if (!isNaN(end as any)) {
             thisExtent[1] = parseFloat(end as any);
         }
     }

     unionExtent(other: [number, number]): void {
         const extent = this._extent;
         other[0] < extent[0] && (extent[0] = other[0]);
         other[1] > extent[1] && (extent[1] = other[1]);

         // unionExtent may called by it's sub classes
         this.setExtent(extent[0], extent[1]);
     }

     getInterval(): number {
         return this._interval;
     }

     setInterval(interval: number): void {
         this._interval = interval;
         // Dropped auto calculated niceExtent and use user setted extent
         // We assume user wan't to set both interval, min, max to get a better result
         this._niceExtent = this._extent.slice() as [number, number];

         this._intervalPrecision = helper.getIntervalPrecision(interval);
     }

     /**
      * @param expandToNicedExtent Whether expand the ticks to niced extent.
      */
     getTicks(expandToNicedExtent?: boolean): ScaleTick[] {
         const interval = this._interval;
         const extent = this._extent;
         const niceTickExtent = this._niceExtent;
         const intervalPrecision = this._intervalPrecision;

         const ticks = [] as ScaleTick[];
         // If interval is 0, return [];
         if (!interval) {
             return ticks;
         }

         // Consider this case: using dataZoom toolbox, zoom and zoom.
         const safeLimit = 10000;

         if (extent[0] < niceTickExtent[0]) {
             if (expandToNicedExtent) {
                 ticks.push({
                     value: roundNumber(niceTickExtent[0] - interval, intervalPrecision)
                 });
             }
             else {
                 ticks.push({
                     value: extent[0]
                 });
             }
         }
         let tick = niceTickExtent[0];

         while (tick <= niceTickExtent[1]) {
             ticks.push({
                 value: tick
             });
             // Avoid rounding error
             tick = roundNumber(tick + interval, intervalPrecision);
             if (tick === ticks[ticks.length - 1].value) {
                 // Consider out of safe float point, e.g.,
                 // -3711126.9907707 + 2e-10 === -3711126.9907707
                 break;
             }
             if (ticks.length > safeLimit) {
                 return [];
             }
         }
         // Consider this case: the last item of ticks is smaller
         // than niceTickExtent[1] and niceTickExtent[1] === extent[1].
         const lastNiceTick = ticks.length ? ticks[ticks.length - 1].value : niceTickExtent[1];
         if (extent[1] > lastNiceTick) {
             if (expandToNicedExtent) {
                 ticks.push({
                     value: roundNumber(lastNiceTick + interval, intervalPrecision)
                 });
             }
             else {
                 ticks.push({
                     value: extent[1]
                 });
             }
         }

         return ticks;
     }

     getMinorTicks(splitNumber: number): number[][] {
         const ticks = this.getTicks(true);
         const minorTicks = [];
         const extent = this.getExtent();

         for (let i = 1; i < ticks.length; i++) {
             const nextTick = ticks[i];
             const prevTick = ticks[i - 1];
             let count = 0;
             const minorTicksGroup = [];
             const interval = nextTick.value - prevTick.value;
             const minorInterval = interval / splitNumber;

             while (count < splitNumber - 1) {
                 const minorTick = roundNumber(prevTick.value + (count + 1) * minorInterval);

                 // For the first and last interval. The count may be less than splitNumber.
                 if (minorTick > extent[0] && minorTick < extent[1]) {
                     minorTicksGroup.push(minorTick);
                 }
                 count++;
             }
             minorTicks.push(minorTicksGroup);
         }

         return minorTicks;
     }

     /**
      * @param opt.precision If 'auto', use nice presision.
      * @param opt.pad returns 1.50 but not 1.5 if precision is 2.
      */
     getLabel(
         data: ScaleTick,
         opt?: {
             precision?: 'auto' | number,
             pad?: boolean
         }
     ): string {
         if (data == null) {
             return '';
         }

         let precision = opt && opt.precision;

         if (precision == null) {
             precision = numberUtil.getPrecisionSafe(data.value) || 0;
         }
         else if (precision === 'auto') {
             // Should be more precise then tick.
             precision = this._intervalPrecision;
         }

         // (1) If `precision` is set, 12.005 should be display as '12.00500'.
         // (2) Use roundNumber (toFixed) to avoid scientific notation like '3.5e-7'.
         const dataNum = roundNumber(data.value, precision as number, true);

         return formatUtil.addCommas(dataNum);
     }

     /**
      * @param splitNumber By default `5`.
      */
     niceTicks(splitNumber?: number, minInterval?: number, maxInterval?: number): void {
         splitNumber = splitNumber || 5;
         const extent = this._extent;
         let span = extent[1] - extent[0];
         if (!isFinite(span)) {
             return;
         }
         // User may set axis min 0 and data are all negative
         // FIXME If it needs to reverse ?
         if (span < 0) {
             span = -span;
             extent.reverse();
         }

         const result = helper.intervalScaleNiceTicks(
             extent, splitNumber, minInterval, maxInterval
         );

         this._intervalPrecision = result.intervalPrecision;
         this._interval = result.interval;
         this._niceExtent = result.niceTickExtent;
     }

     niceExtent(opt: {
         splitNumber: number, // By default 5.
         fixMin?: boolean,
         fixMax?: boolean,
         minInterval?: number,
         maxInterval?: number
     }): void {
         const extent = this._extent;
         // If extent start and end are same, expand them
         if (extent[0] === extent[1]) {
             if (extent[0] !== 0) {
                 // Expand extent
                 const expandSize = extent[0];
                 // In the fowllowing case
                 //      Axis has been fixed max 100
                 //      Plus data are all 100 and axis extent are [100, 100].
                 // Extend to the both side will cause expanded max is larger than fixed max.
                 // So only expand to the smaller side.
                 if (!opt.fixMax) {
                     extent[1] += expandSize / 2;
                     extent[0] -= expandSize / 2;
                 }
                 else {
                     extent[0] -= expandSize / 2;
                 }
             }
             else {
                 extent[1] = 1;
             }
         }
         const span = extent[1] - extent[0];
         // If there are no data and extent are [Infinity, -Infinity]
         if (!isFinite(span)) {
             extent[0] = 0;
             extent[1] = 1;
         }

         this.niceTicks(opt.splitNumber, opt.minInterval, opt.maxInterval);

         // let extent = this._extent;
         const interval = this._interval;

         if (!opt.fixMin) {
             extent[0] = roundNumber(Math.floor(extent[0] / interval) * interval);
         }
         if (!opt.fixMax) {
             extent[1] = roundNumber(Math.ceil(extent[1] / interval) * interval);
         }
     }

 }

 Scale.registerClass(IntervalScale);

 export default IntervalScale;
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/


	import * as numberUtil from '../util/number';
	import * as formatUtil from '../util/format';
	import Scale from './Scale';
	import * as helper from './helper';
	import {ScaleTick, Dictionary} from '../util/types';

	const roundNumber = numberUtil.round;

	class IntervalScale<SETTING extends Dictionary<unknown> = Dictionary<unknown>> extends Scale<SETTING> {

	static type = 'interval';
	type = 'interval';

	// Step is calculated in adjustExtent.
	protected _interval: number = 0;
	protected _niceExtent: [number, number];
	private _intervalPrecision: number = 2;


	parse(val: number): number {
	return val;
	}

	contain(val: number): boolean {
	return helper.contain(val, this._extent);
	}

	normalize(val: number): number {
	return helper.normalize(val, this._extent);
	}

	scale(val: number): number {
	return helper.scale(val, this._extent);
	}

	setExtent(start: number \| string, end: number \| string): void {
	const thisExtent = this._extent;
	// start,end may be a Number like '25',so...
	if (!isNaN(start as any)) {
	thisExtent[0] = parseFloat(start as any);
	}
	if (!isNaN(end as any)) {
	thisExtent[1] = parseFloat(end as any);
	}
	}

	unionExtent(other: [number, number]): void {
	const extent = this._extent;
	other[0] < extent[0] && (extent[0] = other[0]);
	other[1] > extent[1] && (extent[1] = other[1]);

	// unionExtent may called by it's sub classes
	this.setExtent(extent[0], extent[1]);
	}

	getInterval(): number {
	return this._interval;
	}

	setInterval(interval: number): void {
	this._interval = interval;
	// Dropped auto calculated niceExtent and use user setted extent
	// We assume user wan't to set both interval, min, max to get a better result
	this._niceExtent = this._extent.slice() as [number, number];

	this._intervalPrecision = helper.getIntervalPrecision(interval);
	}

	/**
	* @param expandToNicedExtent Whether expand the ticks to niced extent.
	*/
	getTicks(expandToNicedExtent?: boolean): ScaleTick[] {
	const interval = this._interval;
	const extent = this._extent;
	const niceTickExtent = this._niceExtent;
	const intervalPrecision = this._intervalPrecision;

	const ticks = [] as ScaleTick[];
	// If interval is 0, return [];
	if (!interval) {
	return ticks;
	}

	// Consider this case: using dataZoom toolbox, zoom and zoom.
	const safeLimit = 10000;

	if (extent[0] < niceTickExtent[0]) {
	if (expandToNicedExtent) {
	ticks.push({
	value: roundNumber(niceTickExtent[0] - interval, intervalPrecision)
	});
	}
	else {
	ticks.push({
	value: extent[0]
	});
	}
	}
	let tick = niceTickExtent[0];

	while (tick <= niceTickExtent[1]) {
	ticks.push({
	value: tick
	});
	// Avoid rounding error
	tick = roundNumber(tick + interval, intervalPrecision);
	if (tick === ticks[ticks.length - 1].value) {
	// Consider out of safe float point, e.g.,
	// -3711126.9907707 + 2e-10 === -3711126.9907707
	break;
	}
	if (ticks.length > safeLimit) {
	return [];
	}
	}
	// Consider this case: the last item of ticks is smaller
	// than niceTickExtent[1] and niceTickExtent[1] === extent[1].
	const lastNiceTick = ticks.length ? ticks[ticks.length - 1].value : niceTickExtent[1];
	if (extent[1] > lastNiceTick) {
	if (expandToNicedExtent) {
	ticks.push({
	value: roundNumber(lastNiceTick + interval, intervalPrecision)
	});
	}
	else {
	ticks.push({
	value: extent[1]
	});
	}
	}

	return ticks;
	}

	getMinorTicks(splitNumber: number): number[][] {
	const ticks = this.getTicks(true);
	const minorTicks = [];
	const extent = this.getExtent();

	for (let i = 1; i < ticks.length; i++) {
	const nextTick = ticks[i];
	const prevTick = ticks[i - 1];
	let count = 0;
	const minorTicksGroup = [];
	const interval = nextTick.value - prevTick.value;
	const minorInterval = interval / splitNumber;

	while (count < splitNumber - 1) {
	const minorTick = roundNumber(prevTick.value + (count + 1) * minorInterval);

	// For the first and last interval. The count may be less than splitNumber.
	if (minorTick > extent[0] && minorTick < extent[1]) {
	minorTicksGroup.push(minorTick);
	}
	count++;
	}
	minorTicks.push(minorTicksGroup);
	}

	return minorTicks;
	}

	/**
	* @param opt.precision If 'auto', use nice presision.
	* @param opt.pad returns 1.50 but not 1.5 if precision is 2.
	*/
	getLabel(
	data: ScaleTick,
	opt?: {
	precision?: 'auto' \| number,
	pad?: boolean
	}
	): string {
	if (data == null) {
	return '';
	}

	let precision = opt && opt.precision;

	if (precision == null) {
	precision = numberUtil.getPrecisionSafe(data.value) \|\| 0;
	}
	else if (precision === 'auto') {
	// Should be more precise then tick.
	precision = this._intervalPrecision;
	}

	// (1) If `precision` is set, 12.005 should be display as '12.00500'.
	// (2) Use roundNumber (toFixed) to avoid scientific notation like '3.5e-7'.
	const dataNum = roundNumber(data.value, precision as number, true);

	return formatUtil.addCommas(dataNum);
	}

	/**
	* @param splitNumber By default `5`.
	*/
	niceTicks(splitNumber?: number, minInterval?: number, maxInterval?: number): void {
	splitNumber = splitNumber \|\| 5;
	const extent = this._extent;
	let span = extent[1] - extent[0];
	if (!isFinite(span)) {
	return;
	}
	// User may set axis min 0 and data are all negative
	// FIXME If it needs to reverse ?
	if (span < 0) {
	span = -span;
	extent.reverse();
	}

	const result = helper.intervalScaleNiceTicks(
	extent, splitNumber, minInterval, maxInterval
	);

	this._intervalPrecision = result.intervalPrecision;
	this._interval = result.interval;
	this._niceExtent = result.niceTickExtent;
	}

	niceExtent(opt: {
	splitNumber: number, // By default 5.
	fixMin?: boolean,
	fixMax?: boolean,
	minInterval?: number,
	maxInterval?: number
	}): void {
	const extent = this._extent;
	// If extent start and end are same, expand them
	if (extent[0] === extent[1]) {
	if (extent[0] !== 0) {
	// Expand extent
	const expandSize = extent[0];
	// In the fowllowing case
	// Axis has been fixed max 100
	// Plus data are all 100 and axis extent are [100, 100].
	// Extend to the both side will cause expanded max is larger than fixed max.
	// So only expand to the smaller side.
	if (!opt.fixMax) {
	extent[1] += expandSize / 2;
	extent[0] -= expandSize / 2;
	}
	else {
	extent[0] -= expandSize / 2;
	}
	}
	else {
	extent[1] = 1;
	}
	}
	const span = extent[1] - extent[0];
	// If there are no data and extent are [Infinity, -Infinity]
	if (!isFinite(span)) {
	extent[0] = 0;
	extent[1] = 1;
	}

	this.niceTicks(opt.splitNumber, opt.minInterval, opt.maxInterval);

	// let extent = this._extent;
	const interval = this._interval;

	if (!opt.fixMin) {
	extent[0] = roundNumber(Math.floor(extent[0] / interval) * interval);
	}
	if (!opt.fixMax) {
	extent[1] = roundNumber(Math.ceil(extent[1] / interval) * interval);
	}
	}

	}

	Scale.registerClass(IntervalScale);

	export default IntervalScale;