Subtraction operation of JS floating-point number

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The problem is this:37.5*5.5=206.08(JS figure out is such a result, I rounded to take two decimal places) I first suspected is rounding problem, directly with JS a result for:206.08499999999998How can this, two only one decimal number multiplication, how can more out of this decimal point out.　　I Google a bit, found that this is a JavaScript floating point operation of a bug. For example:7*0.8JavaScript calculates that it is:5.6000000000000005Some solutions have been found online, which is to re-write some functions of floating-point arithmetic. Here are excerpts of these methods, for the same problem of Friends Reference: program code//The division function, which is used to get accurate division results.//Description: The result of the division of JavaScript will be error, which will be obvious when dividing two floating-point numbers. This function returns a more accurate division result. //Call: Accdiv (ARG1,ARG2)//return value: Arg1 divided by the exact result of Arg2function Accdiv (arg1, arg2) {varT1 =0, t2 =0, R1, R2; Try{T1 = arg1.tostring (). Split (".")[1].length}Catch(e) {}Try{t2 = arg2.tostring (). Split (".")[1].length}Catch(e) {} with (Math) {R1= Number (arg1.tostring (). Replace (".","")) R2= Number (arg2.tostring (). Replace (".",""))            return(R1/R2) * POW (Ten, T2-t1); }    } //Adding a Div method to the number type makes it easier to call. Number.prototype.div=function (ARG) {returnAccdiv ( This, ARG); } //multiplication function to get the exact multiplication result//Description: JavaScript multiplication results are error-evident when multiplying two floating-point numbers. This function returns a more accurate multiplication result. //Call: Accmul (ARG1,ARG2)//return value: arg1 times the exact result of Arg2function Accmul (arg1, arg2) {varm =0, S1 = arg1.tostring (), S2 =arg2.tostring (); Try{m + = S1.split (".")[1].length}Catch(e) {}Try{m + = S2.split (".")[1].length}Catch(e) {}returnNumber (S1.replace (".","") * Number (S2.replace (".",""))/Math.pow (Ten, M)} //Adding a Mul method to the number type makes it more convenient to call. Number.prototype.mul=function (ARG) {returnAccmul (ARG, This); } //An addition function that is used to obtain accurate addition results//Note: The addition of JavaScript will have an error, and it will be more obvious when the two floating-point numbers are added. This function returns a more accurate addition result. //Call: Accadd (ARG1,ARG2)//return value: Arg1 plus arg2 's exact resultfunction Accadd (arg1, arg2) {varR1, R2, M, C; Try{r1 = arg1.tostring (). Split (".")[1].length}Catch(e) {r1 =0 }        Try{r2 = arg2.tostring (). Split (".")[1].length}Catch(e) {r2 =0} C= Math.Abs (R1-R2); M= Math.pow (Ten, Math.max (R1, r2))if(C >0) {            varCM = Math.pow (Ten, c); if(R1 >R2) {Arg1= Number (arg1.tostring (). Replace (".","")); Arg2= Number (arg2.tostring (). Replace (".","")) *cm; }            Else{arg1= Number (arg1.tostring (). Replace (".","")) *cm; Arg2= Number (arg2.tostring (). Replace (".","")); }        }        Else{arg1= Number (arg1.tostring (). Replace (".","")); Arg2= Number (arg2.tostring (). Replace (".","")); }        return(Arg1 + arg2)/m}//Adding an Add method to the number type makes it more convenient to call. Number.prototype.add=function (ARG) {returnAccadd (ARG, This); }//subtraction function, which is used to get the exact subtraction result//Note: JavaScript subtraction results are error-evident when subtracting two floating-point numbers. This function returns a more accurate subtraction result. //Call: Accsub (ARG1,ARG2)//return value: Arg1 plus arg2 's exact resultfunction Accsub (arg1,arg2) {varR1,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 (Ten, Math.max (R1,R2)); //Last modify by Deeka//Dynamic Control accuracy lengthN= (R1>=R2)?R1:R2; return((arg1*m-arg2*m)/m). toFixed (n);}　　Include these functions where you want them, and then call it to calculate. For example you want to calculate:7*0.8, then change to (7). Mul (8Other operations are similar, so that more accurate results can be obtained. 

Subtraction operation of JS floating-point number