How to use VBScript on a 32-bit operating system to display 64-bit double numbers?

I have a device with 64-digit (double) parameters. I can use Modbus protocol in two parts Read its Double parameter. So I use bitwise operation to divide the 64-digit number into two 32-digit numbers.

Example: 2289225.841082 (decimal) = 41417724-EBA8953E (hexadecimal)< /p>

You can check and test the Hex dialog at the following site: http://babbage.cs.qc.edu/IEEE-754/ copy 41417724EBA8953E and paste the “value to analyze” edit box in the above site , And press Enter.

But after transferring two 32-bit integers, I cannot merge them into the original 64-bit number. I tried to use the CDbl and FormatNumber functions in VBScript, but it failed !

Dim nL, nH, fL, fH, f64 
nL = 1094809380 '4141 7724
nH = 3953694014' EBA8 953E
fL = CDbl($nL)
fH = CDbl($nH)
f64 = CDbl((fH * CDbl(2 ^ 32)) + CDbl(fL))
$strNum64 = ​​FormatNumber( f64 , 2)

So, how to use VBScript to display 64-bit numbers on a 32-bit operating system?

Assuming pure VBScript, the “simple” answer to this is to write a bignum add and multiply and then calculate the answer in this way.

Using the code in RosettaCode, I created the following VeryLargeInteger class and a Hex64 function, which indicates that 4702170486407730494 is the 64-bit decimal equivalent of 0x41417724EBA8953E

Option Explicit
Class VeryLongInteger
'http://rosettacode.org/wiki/Long_Multiplication#Liberty_BASIC
 Public Function MULTIPLY(Str_A, Str_B)
 Dim signA, signB, sResult, Str_Shift, i, d , Str_T
 signA = 1
 If Left(Str_A,1) = "-" Then 
 Str_A = Mid(Str_A,2)
 signA = -1
 End If
 signB = 1
 If Left(Str_B,1) = "-" Then 
 Str_B = Mid(Str_B,2)
 signB = -1
 End If 
 sResult = vbNullString
 Str_T = vbNullString
 Str_shift = vbNullString
 For i = Len(Str_A) To 1 Step -1
 d = CInt(Mid(Str_A,i ,1))
 Str_T = MULTBYDIGIT(Str_B, d)
 sR esult = ADD(sResult, Str_T & Str_shift)
 Str_shift = Str_shift & "0"
'print d, Str_T, sResult 
 Next
 If signA * signB <0 Then sResult = "-" + sResult
'print sResult
 MULTIPLY = sResult
 End Function

 Private Function MULTBYDIGIT(Str_A, d)
 Dim sResult, carry, i, a, c
'multiply Str_A by digit d
 sResult = vbNullString
 carry = 0
 For i = Len(Str_A) To 1 Step -1
 a = CInt(Mid(Str_A,i,1))
 c = a * d + carry
 carry = c \ 10
 c = c Mod 10
'print a, c 
 sResult = CStr(c) & sResult 
 Next
 If carry> 0 Then sResult = CStr(carry) & sResult
'print sResult
 MULTBYDIGIT = sResult
 End Function

 Public Function ADD(Str_A, Str_B)
 Dim L, sResult, carry, i, a, b, c
'add Str_A + Str_B, for now only positive
 l = MAX(Len(Str_A), Len(Str_B))
 Str_A=PAD(Str_A,l)
 Str_B=PAD(Str_B,l)
 sResult = vbNullString'result
 carry = 0
 For i = l To 1 Step -1
 a = CInt(Mid(Str_A, i,1))
 b = CInt(Mid(Str_B,i,1))
 c = a + b + carry
 carry = Int(c/10)
 c = c Mod 10
'print a, b, c
 sResult = CStr(c) & sResult
 Next
 If carry>0 Then sResult = CStr(carry) & sResult< br />'print sResult
 ADD = sResult
 End Function

 Private Function Max(a,b)
 If a> b Then
 Max = a
 Else
 Max = b
 End If
 End Function

 Private Function pad(a,n)'pad from right with 0 to length n 
 Dim sResult
 sResult = a
 While Len(sResult)  sResult = "0" & ​​sResult
 Wend
 pad = sResult
 End Function
End Class

 Function Hex64(sHex)
 Dim VLI
 Set VLI = New VeryLongInteger

 Dim Sixteen(16)
 Sixteen(0) = "1"
 Sixteen (1) = "16"
 Sixteen(2) = VLI.MULTIPLY(Sixteen(1),"16")
 Sixteen(3) = VLI.MULTIPLY(Sixteen(2),"16" )
 Sixteen(4) = VLI.MULTIPLY(Sixteen(3),"16")
 Sixteen(5) = VLI.MULTIPLY(Sixteen(4),"16")
 Sixteen (6) = VLI.MULTIPLY(Sixteen(5),"16")
 Sixteen(7) = VLI.MULTIPLY(Sixteen(6),"16")
 Sixteen(8) = VLI. MULTIPLY(Sixteen(7),"16")
 Sixteen(9) = VLI.MULTIPLY(Sixteen(8),"16")
 Sixteen(10) = VLI.MULTIPLY(Sixteen(9) ,"16")
 Sixteen(11) = VLI.MULTIPLY(Sixteen(10),"16")
 Sixteen(12) = VLI.MULTIPLY(Sixteen(11),"16")< br /> Sixteen(13) = VLI.MULTIPLY(Sixteen(12),"16")
 Sixteen(14) = VLI.MULTIPLY(Sixteen (13),"16")
 Sixteen(15) = VLI.MULTIPLY(Sixteen(14),"16")

 Dim theAnswer, i, theDigit, theMultiplier, thePower, aPower 
 theAnswer = "0"
 aPower = 0
 For i = Len(sHex) To 1 Step -1
 theDigit = UCase(Mid(sHex,i,1))< br /> theMultiplier = InStr("0123456789ABCDEF",theDigit)-1
 thePower = Sixteen(aPower)
 thePower = VLI.MULTIPLY(CStr(theMultiplier),thePower)
 theAnswer = VLI. ADD(theAnswer,thePower )
 aPower = aPower + 1
 Next
 Hex64 = theAnswer
End Function

WScript.Echo Hex64("41417724EBA8953E") 

I want to say “enjoy”, but it’s been more than six months since the original post, so you are likely to find another solution. Still, it’s fun.

Later

Another way to do Hex64, if you want to avoid pre-calculating the power of 16 is:

Function Hex64b(sHex)
 Dim VLI
 Set VLI = New VeryLongInteger 
 Dim theAnswer, i, theDigit, theMultiplier, thePower, aPower
 theAnswer = "0"
 thePower = "1"
 For i = Len(sHex) To 1 St ep -1
 theDigit = UCase(Mid(sHex,i,1))
 theMultiplier = InStr("0123456789ABCDEF",theDigit)-1
 theAnswer = VLI.ADD(theAnswer,VLI. MULTIPLY(thePower,theMultiplier))
 thePower = VLI.MULTIPLY(thePower,"16")
 Next
 Hex64b = theAnswer
End Function

< p>