Tips ： Record the front end here js Some problems in data calculation

JS The accuracy of calculation

One 、 stay vue in , Write a js Method , as follows precisionMath.js

export const precisionMath =  {
    
    methods: {
    
    	//  Add 
        add(arg1, arg2) {
     
          var r1, r2, m, n;
          try {
     r1 = arg1.toString().split(".")[1].length } catch (e) {
     r1 = 0 }
          try {
     r2 = arg2.toString().split(".")[1].length } catch (e) {
     r2 = 0 }
          m = Math.pow(10, Math.max(r1, r2));
          //last modify by deeka
          // Dynamic control precision length 
          n = (r1 >= r2) ? r1 : r2;
          return ((arg1 * m + arg2 * m) / m).toFixed(n);
        },
        //  division 
        except(arg1, arg2) {
    
            var t1 = 0, t2 = 0, r1, r2;
            try {
    
            t1 = arg1.toString().split(".")[1].length
            } catch (e) {
    
            }
            try {
    
            t2 = arg2.toString().split(".")[1].length
            } catch (e) {
    
            }
            r1 = Number(arg1.toString().replace(".", ""))
            r2 = Number(arg2.toString().replace(".", ""))
            return (r1 / r2) * Math.pow(10, t2 - t1);
        },
        //  ride 
        ride(arg1, arg2) {
    
            var m = 0, s1 = arg1.toString(), s2 = arg2.toString();
            try {
     m += s1.split(".")[1].length } catch (e) {
     }
            try {
     m += s2.split(".")[1].length } catch (e) {
     }
            return Number(s1.replace(".", "")) * Number(s2.replace(".", "")) / Math.pow(10, m)
        },
        //  reduce 
        reduce(arg1, arg2) {
    
            var r1, r2, m, n;
            try {
     r1 = arg1.toString().split(".")[1].length } catch (e) {
     r1 = 0 }
            try {
     r2 = arg2.toString().split(".")[1].length } catch (e) {
     r2 = 0 }
            m = Math.pow(10, Math.max(r1, r2));
            //last modify by deeka
            // Dynamic control precision length 
            n = (r1 >= r2) ? r1 : r2;
            return ((arg1 * m - arg2 * m) / m).toFixed(n);
        }
    }
}

Two 、 Used on the page

    import {
      precisionMath } from "@/js/precisionMath"; //  Introduce this in the page js file 
    // precisionMath.methods. Method name ( Parameters 1, Parameters 2)

Keep several decimal places

 retain(num, d) {
    
   return (parseInt(num * 100) / 100).toFixed(d)
},
this.retain(' The number ',' Keep the decimal places ')