echarts/lib/scale/helper.js

Apache ECharts is a powerful, interactive charting and data visualization library for browser

/*
* 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.
*/


/**
 * AUTO-GENERATED FILE. DO NOT MODIFY.
 */

/*
* 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 { getPrecision, round, nice, quantityExponent, mathPow, mathMax, mathRound, mathLog, mathAbs, mathFloor, mathCeil } from '../util/number.js';
import { isValidNumberForExtent } from '../util/model.js';
import { getScaleExtentForTickUnsafe } from './scaleMapper.js';
/**
 * See also method `nice` in `src/util/number.ts`.
 */
// export function isValueNice(val: number) {
//     const exp10 = Math.pow(10, quantityExponent(Math.abs(val)));
//     const f = Math.abs(round(val / exp10, 0));
//     return f === 0
//         || f === 1
//         || f === 2
//         || f === 3
//         || f === 5;
// }
export function isIntervalOrLogScale(scale) {
  return isIntervalScale(scale) || isLogScale(scale);
}
export function isIntervalOrTimeScale(scale) {
  return isIntervalScale(scale) || isTimeScale(scale);
}
export function isIntervalScale(scale) {
  return scale.type === 'interval';
}
export function isTimeScale(scale) {
  return scale.type === 'time';
}
export function isLogScale(scale) {
  return scale.type === 'log';
}
export function isOrdinalScale(scale) {
  return scale.type === 'ordinal';
}
/**
 * @param extent Both extent[0] and extent[1] should be valid number.
 *               Should be extent[0] < extent[1].
 * @param splitNumber splitNumber should be >= 1.
 */
export function intervalScaleNiceTicks(extent, spanWithBreaks, splitNumber, minInterval, maxInterval) {
  var result = {};
  var interval = result.interval = nice(spanWithBreaks / splitNumber, true);
  if (minInterval != null && interval < minInterval) {
    interval = result.interval = minInterval;
  }
  if (maxInterval != null && interval > maxInterval) {
    interval = result.interval = maxInterval;
  }
  var precision = result.intervalPrecision = getIntervalPrecision(interval);
  // Niced extent inside original extent
  result.niceTickExtent = [round(mathCeil(extent[0] / interval) * interval, precision), round(mathFloor(extent[1] / interval) * interval, precision)];
  return result;
}
/**
 * The input `niceInterval` should be generated
 * from `nice` method in `src/util/number.ts`, or
 * from `increaseInterval` itself.
 */
export function increaseInterval(niceInterval) {
  var exponent = quantityExponent(niceInterval);
  // No rounding error in Math.pow(10, integer).
  var exp10 = mathPow(10, exponent);
  // Fix IEEE 754 float rounding error
  var f = mathRound(niceInterval / exp10);
  if (!f) {
    f = 1;
  } else if (f === 2) {
    f = 3;
  } else if (f === 3) {
    f = 5;
  } else {
    // f is 1 or 5
    f *= 2;
  }
  // Fix IEEE 754 float rounding error
  return round(f * exp10, -exponent);
}
export function getIntervalPrecision(niceInterval) {
  // Tow more digital for tick.
  // NOTE: `2` was introduced in commit `af2a2a9f6303081d7c3b52f0a38add07b4c6e0c7`;
  // it works on "nice" interval, but seems not necessarily mathematically required.
  return getPrecision(niceInterval) + 2;
}
/**
 * NOTE:
 *  - If `val` is `NaN`, return `NaN`.
 *  - If `val` is `0`, return `-Infinity`.
 *  - If `val` is negative, return `NaN`.
 *
 * @see {DataStore#getDataExtent} It handles non-positive values for logarithm scale.
 */
export function logScaleLogTick(val, base) {
  // NOTE:
  //  - rounding error may happen above, typically expecting `log10(1000)` but actually
  //    getting `2.9999999999999996`, but generally it does not matter since they are not
  //    used to display.
  //  - Consider backward compatibility and other log bases, do not use `Math.log10`.
  return mathLog(val) / mathLog(base);
}
/**
 * Cumulative rounding errors cause the logarithm operation to become non-invertible by simply exponentiation.
 *  - `Math.pow(10, integer)` itself has no rounding error. But,
 *  - If `linearTickVal` is generated internally by `calcNiceTicks`, it may be still "not nice" (not an integer)
 *    when it is `extent[i]`.
 *  - If `linearTickVal` is generated outside (e.g., by `scaleCalcAlign`) and set by `setExtent`,
 *    `logScaleLogTick` may already have introduced rounding errors even for "nice" values.
 * But invertible is required when the original `extent[i]` need to be respected, or "nice" ticks need to be
 * displayed instead of something like `5.999999999999999`, which is addressed in this function.
 * See also `#4158`.
 *
 * [CAUTION]:
 *  Monotonicity may be broken on extent ends - callers must make sure it does not matter.
 */
export function logScalePowTick(
// `tickVal` should be in the linear space.
linearTickVal, base, opt) {
  var lookup = opt && opt.lookup;
  if (lookup) {
    for (var i = 0; i < lookup.from.length; i++) {
      if (linearTickVal === lookup.from[i]) {
        return lookup.to[i];
      }
    }
  }
  return mathPow(base, linearTickVal);
}
/**
 * For `IntervalScale`, convert `rawExtent` to:
 *  - Be no non-finite number.
 *  - Be `extent[0] < extent[1]`- no equal; otherwise, additional handling is required
 *    in "nice" and "align" ticks.
 */
export function intervalScaleEnsureValidExtent(rawExtent, fixMinMax, rawExtentResult) {
  var extent = rawExtent.slice();
  // PENDING:
  //  This implementation is not rigorous, but has long been in use.
  // If extent start and end are same, expand them
  if (extent[0] === extent[1]) {
    // If `containShape`, the extent must be evenly distributed to both sides;
    // otherwise, shape (e.g., bars) may be overflow and clipped.
    var containShapeRequired = rawExtentResult && rawExtentResult.ctnShp;
    if (extent[0] !== 0) {
      // Expand extent
      // Note that extents can be both negative. See #13154
      var expandSize = mathAbs(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 (!fixMinMax[1]) {
        extent[1] += expandSize / 2;
        extent[0] -= expandSize / 2;
      } else {
        extent[0] -= expandSize / 2;
      }
    } else {
      if (containShapeRequired) {
        extent[0] = -1;
        extent[1] = 1;
      } else {
        extent[1] = 1;
      }
    }
  }
  // For example, if there are no series data, extent may be `[Infinity, -Infinity]` here.
  if (!isValidNumberForExtent(extent[0]) || !isValidNumberForExtent(extent[1])) {
    extent[0] = 0;
    extent[1] = 1;
  }
  if (extent[1] < extent[0]) {
    extent.reverse();
  }
  return extent;
}
export function extentDiffers(extent1, extent2) {
  return [extent1[0] !== extent2[0], extent1[1] !== extent2[1]];
}
export function ensureValidSplitNumber(rawSplitNumber, defaultSplitNumber) {
  rawSplitNumber = rawSplitNumber || defaultSplitNumber;
  return mathRound(mathMax(rawSplitNumber, 1));
}
/**
 * NOTE: The result can have only one item, e.g., when `extent[0] === extent[1]`
 * and `categoryInterval === 0`.
 */
export function ordinalScaleCreateTicks(ordinalScale,
// `categoryInterval` is the number part of `CategoryTickLabelSplitIntervalOption`.
categoryInterval, addItem) {
  var extent = getScaleExtentForTickUnsafe(ordinalScale);
  var startTick = extent[0];
  var tickCount = ordinalScale.count();
  var step = Math.max((categoryInterval || 0) + 1, 1);
  // Calculate start tick based on zero if possible to keep label consistent
  // while zooming and moving while interval > 0. Otherwise the selection
  // of displayable ticks and symbols probably keep changing.
  if (startTick !== 0 && step > 1 && tickCount / step > 2) {
    startTick = Math.round(Math.ceil(startTick / step) * step);
  }
  // min max labels may be excluded if `startTick > 0`, but they should be always
  // included and the label display strategy is adopted uniformly later in `AxisBuilder`.
  if (startTick !== extent[0]) {
    addItemInternally(extent[0], true, true);
  }
  var tickValue = startTick;
  for (; tickValue <= extent[1]; tickValue += step) {
    addItemInternally(tickValue, false, tickValue === extent[0] || tickValue === extent[1]);
  }
  if (tickValue - step !== extent[1]) {
    addItemInternally(extent[1], true, true);
  }
  function addItemInternally(tickValue, offInterval, isExtentBoundary) {
    addItem({
      value: tickValue,
      offInterval: offInterval
    }, isExtentBoundary);
  }
}