@antv/scale
Version:
Toolkit for mapping abstract data into visual representation.
58 lines • 1.8 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.Pow = void 0;
const util_1 = require("@antv/util");
const continuous_1 = require("./continuous");
const utils_1 = require("../utils");
const d3_ticks_1 = require("../tick-methods/d3-ticks");
const transformPow = (exponent) => {
return (x) => {
return x < 0 ? -((-x) ** exponent) : x ** exponent;
};
};
const transformPowInvert = (exponent) => {
return (x) => {
return x < 0 ? -((-x) ** (1 / exponent)) : x ** (1 / exponent);
};
};
const transformSqrt = (x) => {
return x < 0 ? -Math.sqrt(-x) : Math.sqrt(x);
};
/**
* Pow 比例尺
*
* 类似于 linear scale, 不同之处在于在计算输出范围值之前对输入域值应用了指数变换,.
* 即 y = x ^ k 其中 k（指数）可以是任何实数。
*/
class Pow extends continuous_1.Continuous {
getDefaultOptions() {
return {
domain: [0, 1],
range: [0, 1],
nice: false,
clamp: false,
round: false,
exponent: 2,
interpolate: utils_1.createInterpolateValue,
tickMethod: d3_ticks_1.d3Ticks,
tickCount: 5,
};
}
// 显示指定 options 的类型为 PowOptions O 的类型
constructor(options) {
super(options);
}
chooseTransforms() {
const { exponent } = this.options;
if (exponent === 1)
return [util_1.identity, util_1.identity];
const transform = exponent === 0.5 ? transformSqrt : transformPow(exponent);
const untransform = transformPowInvert(exponent);
return [transform, untransform];
}
clone() {
return new Pow(this.options);
}
}
exports.Pow = Pow;
//# sourceMappingURL=pow.js.map