js计算工具

js浮点数计算

// 浮点数加减乘除 https://blog.csdn.net/mafan121/article/details/81354735
/**
 * 浮点数加法
 * @param {} a
 * @param {*} b
 */
export const floatAdd = function(a, b) {
  let m = 0,
    n = 0, //记录a，b的小数位数
    d = a + "", //字符串化
    e = b + "";
  try {
    m = d.split(".")[1] ? d.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  try {
    n = e.split(".")[1] ? e.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  let maxInt = Math.pow(10, Math.max(m, n)); //将数字转换为整数的最大倍数
  return (floatMul(a, maxInt) + floatMul(b, maxInt)) / maxInt;
};

/**
 * 浮点数乘法
 * @param {} a
 * @param {*} b
 */
export const floatMul = function(a, b) {
  let m = 0,
    n = 0, //记录a，b的小数位数
    d = a + "", //字符串化
    e = b + "";
  try {
    m = d.split(".")[1] ? d.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  try {
    n = e.split(".")[1] ? e.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  let maxInt = Math.pow(10, m + n); //将数字转换为整数的最大倍数
  return (Number(d.replace(".", "")) * Number(e.replace(".", ""))) / maxInt;
};

/**
 * 浮点数加法
 * @param {} a
 * @param {*} b
 */
export const floatDivision = function(a, b) {
  let m = 0,
    n = 0, //记录a，b的小数位数
    d = a + "", //字符串化
    e = b + "";
  try {
    m = d.split(".")[1] ? d.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  try {
    n = e.split(".")[1] ? e.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  let maxInt = Math.pow(10, Math.max(n, m)); //将数字转换为整数的最大倍数
  let aInt = floatMul(a, maxInt);
  let bInt = floatMul(b, maxInt);
  return aInt / bInt;
};

//小数减法
export const floatSub = (a, b) => {
  let m = 0,
    n = 0, //记录a，b的小数位数
    d = a + "", //字符串化
    e = b + "";
  try {
    m = d.split(".")[1] ? d.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  try {
    n = e.split(".")[1] ? e.split(".")[1].length : "";
  } catch (error) {
    console.log(error);
  }
  let maxInt = Math.pow(10, Math.max(m, n)); //将数字转换为整数的最大倍数
  return (floatMul(a, maxInt) - floatMul(b, maxInt)) / maxInt;
};