浮点数计算

偶尔在一些git代码中看到一些关于浮点数运算的代码,拿过来备用之后可以用下.

//浮点数相加
export const MathAdd = (a, b) => {
  a = a ? a : 0;
  b = b ? b : 0;
  var c, d, e;
  try {
    c = a.toString().split('.')[1].length;
  } catch (f) {
    c = 0;
  }
  try {
    d = b.toString().split('.')[1].length;
  } catch (f) {
    d = 0;
  }
  return (e = Math.pow(10, Math.max(c, d))), (MathMul(a, e) + MathMul(b, e)) / e;
};

// 浮点数相减
export const MathSub = (a, b) => {
  a = a ? a : 0;
  b = b ? b : 0;
  var c, d, e;
  try {
    c = a.toString().split('.')[1].length;
  } catch (f) {
    c = 0;
  }
  try {
    d = b.toString().split('.')[1].length;
  } catch (f) {
    d = 0;
  }
  return (e = Math.pow(10, Math.max(c, d))), (MathMul(a, e) - MathMul(b, e)) / e;
};

// 浮点数相乘
export const MathMul = (a, b) => {
  a = a ? a : 0;
  b = b ? b : 0;
  var c = 0,
    d = a.toString(),
    e = b.toString();
  try {
    c += d.split('.')[1].length;
  } catch (f) {}
  try {
    c += e.split('.')[1].length;
  } catch (f) {}
  return (Number(d.replace('.', '')) * Number(e.replace('.', ''))) / Math.pow(10, c);
};

// 浮点数相除
export const MathDiv = (a, b) => {
  a = a ? a : 0;
  b = b ? b : 0;
  var c,
    d,
    e = 0,
    f = 0;
  try {
    e = a.toString().split('.')[1].length;
  } catch (g) {}
  try {
    f = b.toString().split('.')[1].length;
  } catch (g) {}
  return (c = Number(a.toString().replace('.', ''))), (d = Number(b.toString().replace('.', ''))), MathMul(c / d, Math.pow(10, f - e));
};