recharts
Version:
React charts
218 lines (206 loc) • 9.3 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.getValidInterval = exports.getTickValuesFixedDomain = exports.getTickOfSingleValue = exports.getNiceTickValues = exports.getFormatStep = exports.calculateStep = void 0;
var _decimal = _interopRequireDefault(require("decimal.js-light"));
var _utils = require("./util/utils");
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 getFormatStep = (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()));
};
/**
* 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.getFormatStep = getFormatStep;
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 fn = (0, _utils.compose)((0, _utils.map)(n => middle.add(new _decimal.default(n - middleIndex).mul(step)).toNumber()), _utils.range);
return fn(0, tickCount);
};
/**
* 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;
// 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 = getFormatStep(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);
}
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
* @return array of ticks
*/
function getNiceTickValuesFn(_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;
// 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, ...(0, _utils.range)(0, tickCount - 1).map(() => Infinity)] : [...(0, _utils.range)(0, tickCount - 1).map(() => -Infinity), cormax];
return min > max ? (0, _utils.reverse)(_values) : _values;
}
if (cormin === cormax) {
return getTickOfSingleValue(cormin, tickCount, allowDecimals);
}
// Get the step between two ticks
var {
step,
tickMin,
tickMax
} = _calculateStep(cormin, cormax, count, allowDecimals, 0);
var values = (0, _arithmetic.rangeStep)(tickMin, tickMax.add(new _decimal.default(0.1).mul(step)), step);
return min > max ? (0, _utils.reverse)(values) : 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
* @return array of ticks
*/
function getTickValuesFixedDomainFn(_ref3, tickCount) {
var [min, max] = _ref3;
var allowDecimals = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : true;
// 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 count = Math.max(tickCount, 2);
var step = getFormatStep(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 ? (0, _utils.reverse)(values) : values;
}
var getNiceTickValues = exports.getNiceTickValues = (0, _utils.memoize)(getNiceTickValuesFn);
var getTickValuesFixedDomain = exports.getTickValuesFixedDomain = (0, _utils.memoize)(getTickValuesFixedDomainFn);