BD-09 墨卡托坐标转 BD-09 经纬度

以下是 JavaScript 实现， BD-09 墨卡托坐标转 BD-09 经纬度：

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JavaScript 实现

// 常量定义
const MCBAND = [12890594.86, 8362377.87, 5591021, 3481989.83, 1678043.12, 0];
const MC2LL = [
    [1.410526172116255e-8, 0.00000898305509648872, -1.9939833816331,
     200.9824383106796, -187.2403703815547, 91.6087516669843, -23.38765649603339,
     2.57121317296198, -0.03801003308653, 17337981.2],
    [-7.435856389565537e-9, 0.000008983055097726239, -0.78625201886289,
     96.32687599759846, -1.85204757529826, -59.36935905485877, 47.40033549296737,
     -16.50741931063887, 2.28786674699375, 10260144.86],
    [-3.030883460898826e-8, 0.00000898305509983578, 0.30071316287616,
     59.74293618442277, 7.357984074871, -25.38371002664745, 13.45380521110908,
     -3.29883767235584, 0.32710905363475, 6856817.37],
    [-1.981981304930552e-8, 0.000008983055099779535, 0.03278182852591, 40.31678527705744,
     0.65659298677277, -4.44255534477492, 0.85341911805263, 0.12923347998204,
     -0.04625736007561, 4482777.06],
    [3.09191371068437e-9, 0.000008983055096812155, 0.00006995724062, 23.10934304144901,
     -0.00023663490511, -0.6321817810242, -0.00663494467273, 0.03430082397953,
     -0.00466043876332, 2555164.4],
    [2.890871144776878e-9, 0.000008983055095805407, -3.068298e-8, 7.47137025468032,
     -0.00000353937994, -0.02145144861037, -0.00001234426596, 0.00010322952773,
     -0.00000323890364, 826088.5]
];
const X_PI = 3.14159265358979324 * 3000.0 / 180.0;

// 墨卡托坐标转 BD-09 经纬度
function convertMCTToBD09(lon, lat) {
    let ax = null;

    // 获取常量 ax
    for (let j = 0; j < MCBAND.length; j++) {
        if (lat >= MCBAND[j]) {
            ax = MC2LL[j];
            break;
        }
    }

    if (!ax) {
        throw new Error(`Error lat: ${lat}`);
    }

    let e = ax[0] + ax[1] * Math.abs(lon);
    const i = Math.abs(lat) / ax[9];
    let aw = ax[2] + ax[3] * i + ax[4] * i * i + ax[5] * i * i * i +
             ax[6] * i * i * i * i + ax[7] * i * i * i * i * i + ax[8] * i * i * i * i * i * i;

    if (lon < 0) {
        e *= -1;
    }
    if (lat < 0) {
        aw *= -1;
    }

    return [e, aw];
}

// 示例：批量转换墨卡托坐标
const mocatorLngLat = [
    13271401.86, 2985177.68, 13271454.86, 2985165.68, 13271642.86, 2985215.68,
    13271655.86, 2985236.68, 13271576.86, 2985392.68, 13271555.86, 2985417.68,
    13271459.86, 2985656.68, 13271412.86, 2985822.67, 13271388.86, 2985840.67,
    13271112.86, 2985770.68, 13271102.86, 2985724.68, 13271401.86, 2985177.68
];

const baiduLngLatList = [];
for (let i = 0; i < mocatorLngLat.length / 2; i++) {
    const lon = mocatorLngLat[i * 2];
    const lat = mocatorLngLat[i * 2 + 1];
    const bd09 = convertMCTToBD09(lon, lat);
    baiduLngLatList.push(bd09);
}

console.log(baiduLngLatList); // 输出 BD-09 经纬度列表

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代码说明

1. convertMCTToBD09(lon, lat)

   • 输入：墨卡托坐标 (lon, lat)（单位：米）。
   • 输出：BD-09 经纬度 [lng, lat]（单位：度）。
   • 逻辑：根据 MCBAND 和 MC2LL 查表计算。

2. 批量处理

   • 遍历输入的墨卡托坐标数组，逐个转换并存储结果。

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注意事项

1. 注明“非官方实现，可能存在误差”；