やりたい事

DMS(※1)形式 から Degree形式 に変換したい

つまりタイトル通り 60進数 to 10進数 をしたい
10進数 to 60進数も↓の方で実装してます

e.g.) 東京の緯度経度
DMS形式 [35度39分10.1952秒, 139度50分22.1208秒]
↓
Degree形式 [35.652832, 139.839478]

※1 Degree Minute Second の略

実装

interface PointInDMS {
  lat: DMS;
  lng: DMS;
}

interface PointInDegree {
  lat: number;
  lng: number;
}

interface DMS {
  degree: number;
  minute: number;
  second: number;
}

const degreeMinuteSecond2Degree = (pointInDMS: PointInDMS): PointInDegree => {
  return {
    lat:
      pointInDMS.lat.degree +
      pointInDMS.lat.minute / 60 +
      pointInDMS.lat.second / 60 / 60,
    lng:
      pointInDMS.lng.degree +
      pointInDMS.lng.minute / 60 +
      pointInDMS.lng.second / 60 / 60
  };
};

export const main = () => {
  // 東京
  const tokyoPoint: PointInDMS = {
    lat: { degree: 35, minute: 39, second: 10.1952 },
    lng: { degree: 139, minute: 50, second: 22.1208 }
  };
  console.log({ tokyoPoint });

  const deg: PointInDegree = degreeMinuteSecond2Degree(tokyoPoint);
  console.log({ deg });
};

main();

実行結果

{
  tokyoPoint: {
    lat: { degree: 35, minute: 39, second: 10.1952 },
    lng: { degree: 139, minute: 50, second: 22.1208 }
  }
}
{ deg: { lat: 35.652832, lng: 139.839478 } }

逆もやってみた

10進数 to 60進数

一般的にDegree形式が使われてると思うので、こちらを使う事が多そう

interface PointInDMS {
  lat: DMS;
  lng: DMS;
}

interface PointInDegree {
  lat: number;
  lng: number;
}

interface DMS {
  degree: number;
  minute: number;
  second: number;
}

const degreeMinuteSecond2Degree = (pointInDMS: PointInDMS): PointInDegree => {
  return {
    lat:
      pointInDMS.lat.degree +
      pointInDMS.lat.minute / 60 +
      pointInDMS.lat.second / 60 / 60,
    lng:
      pointInDMS.lng.degree +
      pointInDMS.lng.minute / 60 +
      pointInDMS.lng.second / 60 / 60
  };
};

const degree2DegreeMinuteSecond = (pointInDMS: PointInDegree): PointInDMS => {
  const d2dms = (degree: number): DMS => {
    const minuteSecond = parseFloat("0." + degree.toString().split(".")[1]) * 60;
    return {
      degree: Math.trunc(degree),
      minute: Math.trunc(minuteSecond),
      second: parseFloat("0." + minuteSecond.toString().split(".")[1]) * 60
    };
  };

  return {
    lat: d2dms(pointInDMS.lat),
    lng: d2dms(pointInDMS.lng)
  };
};

export const main = () => {
  // 東京
  const tokyoPoint: PointInDMS = {
    lat: { degree: 35, minute: 39, second: 10.1952 },
    lng: { degree: 139, minute: 50, second: 22.1208 }
  };
  console.log({ tokyoPoint });

  const deg: PointInDegree = degreeMinuteSecond2Degree(tokyoPoint);
  console.log({ deg });

  const dms: PointInDMS = degree2DegreeMinuteSecond(deg);
  console.log({ dms });
};

main();

実行結果

{
  tokyoPoint: {
    lat: { degree: 35, minute: 39, second: 10.1952 },
    lng: { degree: 139, minute: 50, second: 22.1208 }
  }
}
{ deg: { lat: 35.652832, lng: 139.839478 } }
{
  dms: {
    lat: { degree: 35, minute: 39, second: 10.1952 },
    lng: { degree: 139, minute: 50, second: 22.1208 }
  }
}