67 lines
2.1 KiB
JavaScript
67 lines
2.1 KiB
JavaScript
// 使用这些方法，仍然需要注意数值范围、舍入策略和比较运算等方面的问题，根据具体的应用场景进行适当的调整和处理。
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const math = {
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// 加法运算
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add: function (a, b) {
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const precision = Math.max(getPrecision(a), getPrecision(b));
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const multiplier = Math.pow(10, precision);
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const result=(Math.round(a * multiplier) + Math.round(b * multiplier)) / multiplier;
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return transferToNumber(result)
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},
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// 减法运算
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subtract: function (a, b) {
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return transferToNumber(math.add(a, -b));
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},
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// 乘法运算
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multiply: function (a, b) {
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const precision = getPrecision(a) + getPrecision(b);
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const multiplier = Math.pow(10, precision);
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const result=(Math.round(a * multiplier) * Math.round(b * multiplier)) / (multiplier * multiplier);
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return transferToNumber(result)
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},
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// 除法运算
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divide: function (num1, num2) {
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var str1 = Number(num1).toString(),
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str2 = Number(num2).toString(),
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result,
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str1Length,
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str2Length;
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//解决整数没有小数点方法
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try {
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str1Length = str1.split(".")[1].length;
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} catch (error) {
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str1Length = 0;
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}
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try {
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str2Length = str2.split(".")[1].length;
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} catch (error) {
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str2Length = 0;
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}
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var step = Math.pow(10, Math.max(str1Length, str2Length));
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result = (num1 * step) / (num2 * step);
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return transferToNumber(result);
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},
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// 获取浮点数的小数位数
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};
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function getPrecision(num) {
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const str = String(num);
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const decimalIndex = str.indexOf(".");
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return decimalIndex === -1 ? 0 : str.length - decimalIndex - 1;
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}
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// 处理出现科学计数法
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function transferToNumber(num) {
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if (isNaN(num)) {
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return num
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}
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num = '' + num
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num = parseFloat(num)
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let eformat = num.toExponential() // 转换为标准的科学计数法形式（字符串）
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let tmpArray = eformat.match(/\d(?:\.(\d*))?e([+-]\d+)/) // 分离出小数值和指数值
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let number = num.toFixed(Math.max(0, (tmpArray[1] || '').length - tmpArray[2]))
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return number
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}
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export default math;
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