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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.getValidInterval = exports.getTickValuesFixedDomain = exports.getTickOfSingleValue = exports.getSnap125Step = exports.getNiceTickValues = exports.getAdaptiveStep = exports.calculateStep = void 0; var _decimal = _interopRequireDefault(require("decimal.js-light")); var _arithmetic = require("./util/arithmetic"); function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; } /** * @fileOverview calculate tick values of scale * @author xile611, arcthur * @date 2015-09-17 */ /** * Calculate a interval of a minimum value and a maximum value * * @param {Number} min The minimum value * @param {Number} max The maximum value * @return {Array} An interval */ var getValidInterval = _ref => { var [min, max] = _ref; var [validMin, validMax] = [min, max]; // exchange if (min > max) { [validMin, validMax] = [max, min]; } return [validMin, validMax]; }; /** * Calculate the step which is easy to understand between ticks, like 10, 20, 25 * * @param roughStep The rough step calculated by dividing the difference by the tickCount * @param allowDecimals Allow the ticks to be decimals or not * @param correctionFactor A correction factor * @return The step which is easy to understand between two ticks */ exports.getValidInterval = getValidInterval; var getAdaptiveStep = (roughStep, allowDecimals, correctionFactor) => { if (roughStep.lte(0)) { return new _decimal.default(0); } var digitCount = (0, _arithmetic.getDigitCount)(roughStep.toNumber()); // The ratio between the rough step and the smallest number which has a bigger // order of magnitudes than the rough step var digitCountValue = new _decimal.default(10).pow(digitCount); var stepRatio = roughStep.div(digitCountValue); // When an integer and a float multiplied, the accuracy of result may be wrong var stepRatioScale = digitCount !== 1 ? 0.05 : 0.1; var amendStepRatio = new _decimal.default(Math.ceil(stepRatio.div(stepRatioScale).toNumber())).add(correctionFactor).mul(stepRatioScale); var formatStep = amendStepRatio.mul(digitCountValue); return allowDecimals ? new _decimal.default(formatStep.toNumber()) : new _decimal.default(Math.ceil(formatStep.toNumber())); }; exports.getAdaptiveStep = getAdaptiveStep; /** * The snap125 step algorithm snaps to nice numbers (1, 2, 2.5, 5) at each * order of magnitude, producing human-friendly tick intervals like * 0, 5, 10, 15, 20 instead of 0, 4, 8, 12, 16. * * This is opt-in and can be enabled via the `niceTicks` prop on axis components. * * @param roughStep The rough step calculated by dividing the difference by the tickCount * @param allowDecimals Allow the ticks to be decimals or not * @param correctionFactor A correction factor * @return The step which is easy to understand between two ticks */ var getSnap125Step = (roughStep, allowDecimals, correctionFactor) => { var _NICE_STEPS$niceIdx; if (roughStep.lte(0)) { return new _decimal.default(0); } var NICE_STEPS = [1, 2, 2.5, 5]; var roughNum = roughStep.toNumber(); var exponent = Math.floor(new _decimal.default(roughNum).abs().log(10).toNumber()); var magnitude = new _decimal.default(10).pow(exponent); // normalized is in the range [1, 10) var normalized = roughStep.div(magnitude).toNumber(); // Find the smallest nice step >= normalized (ceiling) var niceIdx = NICE_STEPS.findIndex(s => s >= normalized - 1e-10); if (niceIdx === -1) { // normalized > 5 (e.g. 7.3), move to next order of magnitude magnitude = magnitude.mul(10); niceIdx = 0; } // Apply correction factor by stepping through the nice number sequence niceIdx += correctionFactor; if (niceIdx >= NICE_STEPS.length) { var extraMag = Math.floor(niceIdx / NICE_STEPS.length); niceIdx %= NICE_STEPS.length; magnitude = magnitude.mul(new _decimal.default(10).pow(extraMag)); } var niceStep = (_NICE_STEPS$niceIdx = NICE_STEPS[niceIdx]) !== null && _NICE_STEPS$niceIdx !== void 0 ? _NICE_STEPS$niceIdx : 1; var formatStep = new _decimal.default(niceStep).mul(magnitude); return allowDecimals ? formatStep : new _decimal.default(Math.ceil(formatStep.toNumber())); }; /** * calculate the ticks when the minimum value equals to the maximum value * * @param value The minimum value which is also the maximum value * @param tickCount The count of ticks * @param allowDecimals Allow the ticks to be decimals or not * @return array of ticks */ exports.getSnap125Step = getSnap125Step; var getTickOfSingleValue = (value, tickCount, allowDecimals) => { var step = new _decimal.default(1); // calculate the middle value of ticks var middle = new _decimal.default(value); if (!middle.isint() && allowDecimals) { var absVal = Math.abs(value); if (absVal < 1) { // The step should be a float number when the difference is smaller than 1 step = new _decimal.default(10).pow((0, _arithmetic.getDigitCount)(value) - 1); middle = new _decimal.default(Math.floor(middle.div(step).toNumber())).mul(step); } else if (absVal > 1) { // Return the maximum integer which is smaller than 'value' when 'value' is greater than 1 middle = new _decimal.default(Math.floor(value)); } } else if (value === 0) { middle = new _decimal.default(Math.floor((tickCount - 1) / 2)); } else if (!allowDecimals) { middle = new _decimal.default(Math.floor(value)); } var middleIndex = Math.floor((tickCount - 1) / 2); var ticks = []; for (var i = 0; i < tickCount; i++) { ticks.push(middle.add(new _decimal.default(i - middleIndex).mul(step)).toNumber()); } return ticks; }; /** * Calculate the step * * @param min The minimum value of an interval * @param max The maximum value of an interval * @param tickCount The count of ticks * @param allowDecimals Allow the ticks to be decimals or not * @param correctionFactor A correction factor * @return The step, minimum value of ticks, maximum value of ticks */ exports.getTickOfSingleValue = getTickOfSingleValue; var _calculateStep = exports.calculateStep = function calculateStep(min, max, tickCount, allowDecimals) { var correctionFactor = arguments.length > 4 && arguments[4] !== undefined ? arguments[4] : 0; var stepFn = arguments.length > 5 && arguments[5] !== undefined ? arguments[5] : getAdaptiveStep; // dirty hack (for recharts' test) if (!Number.isFinite((max - min) / (tickCount - 1))) { return { step: new _decimal.default(0), tickMin: new _decimal.default(0), tickMax: new _decimal.default(0) }; } // The step which is easy to understand between two ticks var step = stepFn(new _decimal.default(max).sub(min).div(tickCount - 1), allowDecimals, correctionFactor); // A medial value of ticks var middle; // When 0 is inside the interval, 0 should be a tick if (min <= 0 && max >= 0) { middle = new _decimal.default(0); } else { // calculate the middle value middle = new _decimal.default(min).add(max).div(2); // minus modulo value middle = middle.sub(new _decimal.default(middle).mod(step)); } var belowCount = Math.ceil(middle.sub(min).div(step).toNumber()); var upCount = Math.ceil(new _decimal.default(max).sub(middle).div(step).toNumber()); var scaleCount = belowCount + upCount + 1; if (scaleCount > tickCount) { // When more ticks need to cover the interval, step should be bigger. return _calculateStep(min, max, tickCount, allowDecimals, correctionFactor + 1, stepFn); } if (scaleCount < tickCount) { // When less ticks can cover the interval, we should add some additional ticks upCount = max > 0 ? upCount + (tickCount - scaleCount) : upCount; belowCount = max > 0 ? belowCount : belowCount + (tickCount - scaleCount); } return { step, tickMin: middle.sub(new _decimal.default(belowCount).mul(step)), tickMax: middle.add(new _decimal.default(upCount).mul(step)) }; }; /** * Calculate the ticks of an interval. Ticks can appear outside the interval * if it makes them more rounded and nice. * * @param tuple of [min,max] min: The minimum value, max: The maximum value * @param tickCount The count of ticks * @param allowDecimals Allow the ticks to be decimals or not * @param niceTicksMode The algorithm to use for calculating nice ticks. * @return array of ticks */ var getNiceTickValues = exports.getNiceTickValues = function getNiceTickValues(_ref2) { var [min, max] = _ref2; var tickCount = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 6; var allowDecimals = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : true; var niceTicksMode = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : 'auto'; // More than two ticks should be return var count = Math.max(tickCount, 2); var [cormin, cormax] = getValidInterval([min, max]); if (cormin === -Infinity || cormax === Infinity) { var _values = cormax === Infinity ? [cormin, ...Array(tickCount - 1).fill(Infinity)] : [...Array(tickCount - 1).fill(-Infinity), cormax]; return min > max ? _values.reverse() : _values; } if (cormin === cormax) { return getTickOfSingleValue(cormin, tickCount, allowDecimals); } var stepFn = niceTicksMode === 'snap125' ? getSnap125Step : getAdaptiveStep; // Get the step between two ticks var { step, tickMin, tickMax } = _calculateStep(cormin, cormax, count, allowDecimals, 0, stepFn); var values = (0, _arithmetic.rangeStep)(tickMin, tickMax.add(new _decimal.default(0.1).mul(step)), step); return min > max ? values.reverse() : values; }; /** * Calculate the ticks of an interval. * Ticks will be constrained to the interval [min, max] even if it makes them less rounded and nice. * * @param tuple of [min,max] min: The minimum value, max: The maximum value * @param tickCount The count of ticks. This function may return less than tickCount ticks if the interval is too small. * @param allowDecimals Allow the ticks to be decimals or not * @param niceTicksMode The algorithm to use for calculating nice ticks. See {@link NiceTicksAlgorithm}. * @return array of ticks */ var getTickValuesFixedDomain = exports.getTickValuesFixedDomain = function getTickValuesFixedDomain(_ref3, tickCount) { var [min, max] = _ref3; var allowDecimals = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : true; var niceTicksMode = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : 'auto'; // More than two ticks should be return var [cormin, cormax] = getValidInterval([min, max]); if (cormin === -Infinity || cormax === Infinity) { return [min, max]; } if (cormin === cormax) { return [cormin]; } var stepFn = niceTicksMode === 'snap125' ? getSnap125Step : getAdaptiveStep; var count = Math.max(tickCount, 2); var step = stepFn(new _decimal.default(cormax).sub(cormin).div(count - 1), allowDecimals, 0); var values = [...(0, _arithmetic.rangeStep)(new _decimal.default(cormin), new _decimal.default(cormax), step), cormax]; if (allowDecimals === false) { /* * allowDecimals is false means that we want to have integer ticks. * The step is guaranteed to be an integer in the code above which is great start * but when the first step is not an integer, it will start stepping from a decimal value anyway. * So we need to round all the values to integers after the fact. */ values = values.map(value => Math.round(value)); } return min > max ? values.reverse() : values; };