[RESOLVED] Denary (Base 10) to Binary (Base 2)

i am trying to convert Denary numbers to a binary value, using two's compliments, but the i am using is coming back wrong. any help will be greatly apreciated.

Code:

---

Option Explicit
Public Function InputNumber(Numpass As Double) As String
Dim Bintemp As String
    While Numpass >= 0 'while number is greater or equal to 1
        Bintemp = Bintemp & Numpass Mod 2 'Divides by 2 each time and collects the remainder
            If OddEven(Numpass) = True Then
                Bintemp = Bintemp & "0"
            Else
                Bintemp = Bintemp & "1"
            End If
      Numpass = (Numpass / 2)
      Wend
InputNumber = Bintemp
End Function
Public Function OddEven(num As Integer) As Boolean 'true of false
    If num Mod 2 = 0 Then
        OddEven = True 'Even
    Else
        OddEven = False 'False
    End If
End Function
Public Sub Calculate()
Dim StrBinary As String, temp As Integer
    If Form1.OptBinary.Value = True Then
        temp = Form1.txtNumber.Text
        StrBinary = StrReverse(InputNumber(temp))
        Form1.txtAnswer.Text = StrBinary
    End If
    If Form1.OptOctal.Value = True Then
        temp = Form1.txtNumber.Text
        StrBinary = Oct(temp)
        Form1.txtAnswer.Text = StrBinary
    End If
    If Form1.OptDenary.Value = True Then
        temp = Form1.txtNumber.Text
        StrBinary = temp
        Form1.txtAnswer.Text = StrBinary
    End If
    If Form1.OptHexidecimal.Value = True Then
        temp = Form1.txtNumber.Text
        StrBinary = Hex(temp)
        Form1.txtAnswer.Text = StrBinary
    End If
   
End Sub

---

I find this odd.

While Numpass >= 0 'while number is greater or equal to 1

should be >=1 in the first place.

If you're talking about (for instance) turning 256 into 11111111 (converting base-10 values to binary true/false representations, base-2) then there's an easier way to do it

Remember the following piece of information...It's been useful to me for many years :-)
if denary and 256 then bit(8) =1
if denary and 128 then bit(7) = 1
if denary and 64 then bit(6) = 1
(etc)
if denary and 1 then bit(0) = 1

Using the AND operator here is a very useful way to work out which bits should be noted...and you can make this shorter still if you write it all into a clever loop...if you *really* need me to, I could probably write a den2bin function for you :-)

Im unsure what u mean smUX,
but how could u display on the text box the binary value or something like

24 or 200?

for example for 24 the answer should display on the textbox 11000

Well, bin(0) to bin(7) would have the binary values for the bytes, so if you added these together into a string backwards (7 to 0) then yes it would come out like "11000" if the number was 24 (and if 11000 is the binary representation, of course :-))

Gimme 5 mins and I'll write a quick function that can handle the string building from denary to binary...back to denary is a simple matter, I'm sure :-)

Okay, here it is :-)

The function itself is:

Code:

---

Private Function den2bin(den As Double)
sta = 16777216
For b = 24 To 1 Step -1
sta = sta / 2
If den And sta Then x = x & "1" Else x = x & "0"
Next b
den2bin = x
End Function

---

and if you want to test it out natively (in a pre-designed form) you can download the attachment

This function uses a slightly different method to the one I previously mentioned...this is the condensed version and can in theory handle any length of bits if you set sta (starting value)...24 bit has a max value of 16777216, which is what I have sta set as...if you want 32 bit, change sta to 4294967296, if you want 16 bit change it to 65536...etcetera :-)

omg! its crazy!

i dont understand any of this!

can u do this in a simplier version?

im only a college student!

Okay, I assume you're trying to learn from this...let me go a bit simpler :-)

The AND operator in this case looks at the number on a binary level...if you do "24 and 1 it returns false because the number at the "1" point in the binary equivalent "11000" is 0 (the 5th digit). If you however did "24 and 16" or "24 and 8" you would get true, because those bits in the byte are 1s...it's just the way it works in most programming languages, and I've brought that nugget of info back from my Commodore 64/Commodore +4 programming days (yes, rhinobull, I've been programming that long...I'm sure you still think I've only been at it a few years...I started programming a little under 20 years ago and I'm not even 30 yet...just always have been amateur and haven't wanted to go pro or learn what I needed to :-P)

Master or Frozen, if you have any more questions feel free to ask

ok i understand a bit then, sta is the starting possition and the den is the denary value. what is x and b

Smux, that's the question you'd get for not properly declaring variables. As a general rule, put Option Explicit.

And I quote:

Quote:

---

Originally Posted by smUX

Gimme 5 mins and I'll write a quick function that can handle the string building from denary to binary...back to denary is a simple matter, I'm sure :-)

---

Quick means I don't add in tons of declarations and comments...just the code that makes it work :-)

I was going to also write in a bit of code to trim the leading 0s, but decided against it and kept it simple :-P

Frozen, X and B are just temporary variables that I am using in the code...you should be able to scan through the *few* lines of code to work out where they're being used :-P

is there any other way of doing this?

cus the design work (flow charts) i did

it goes

Start

Input Number

Select Which Base

Calculate

Display Answer

End

im thinking thats right, the way ur saying seems right but

i've never used that before...

i dont really understand... i only know very very basic of VB :S

However, here's a more detailed version with the right stuff in there

Code:

---

Private Function den2bin(den As Double)
dim sta as double, x as string
'Sta = starting value.  The value in this case is a 24-bit number and the value
'of the 25th bit...it is divided by 2 at each point and each successive number
'is the value of the next lowest bit...sta/2 is the 24th bit, /2 again is the 23rd
'until you get to 1 which is the 1st bit
sta = 16777216
For b = 1 To 24
sta = sta / 2
'X here is unimportant...it's a temporary string storing the binary data as it
'is being built
If den And sta Then x = x & "1" Else x = x & "0"
Next b
'This is how functions work.  Notice how the first part "den2bin" is the name
'of this function...saying "den2bin = x" is saying to return the value of x as
'the returned value from the function...functions return values :-P
den2bin = x
End Function

---

Yes, I removed the step -1 and made it 1 to 24...I originally was going to use the original idea with the array but decided against it :-)

Master, this code would only be useful for base 2 (binary) but I am sure there's ways of doing different bases...possibly using a modified version of this bit of code...as I've not worked with anything but base 2 and base 10, I've no idea how feasible it would be and if so how *easy* it would be :-)

could you just explan

Code:

---

For b = 16 To 1 Step -1
sta = sta / 2
If den And sta Then x = x & "1" Else x = x & "0"
Next b

---

then i abit more detail
especally

Code:

---

If den And sta Then x = x & "1" Else x = x & "0"

---

The first one is 24 to 1 step -1 not 16, but that's not an issue...the for/next is a loop which repeats the code within 24 times

Sta is divided by 2 at each iteration, dropping from 16.7m down to 1 at the 24th interval...and at each interval that's what the bit at that point is valued at. At each point, if the base 2 value would be 1 it adds the character "1" to the string X and if the base 2 value would be 0 it adds the character "0" to the string

the "den and sta" thing is simple. "den" is the denary number (the proper base 10 number we're converting from) and "sta" is the binary bit we're looking at...if the bit is there, "den and sta" would return true and would do the first bit...if not it would do the "else" bit of the line

thanx i understand now, it has really helped

Glad to hear it...I help where I can :-)

Don't forget to mark this thread as resolved if you feel you've got the info you need, so others know they can concentrate on ones that haven't been resolved :-P

Okay, people weren't expecting this, but here's an updated version which makes use of *ANY* base, it can do base 2 (binary), base 3 (trinary) and all the others...it makes use of a simple enough trick which I am sure most people here can work out...it *isn't* fast, I've not optimized the code in any way yet, although I dunno if I need to because it isn't like it's too slow to use...when I say it isn't fast, I mean it's unoptimized :-P

Anyway, first use http://www.mathsisfun.com/numbers/convert-base.php and get yourself a test value if you want to test this. Me, I used 100 and base 3 which should return 10201 in trinary and it seems to work fine

Here's the updated function, and notice it now needs to be sent more than just the source number now through the command!

Code:

---

Private Function den2bin(den As Double, base As Single, bits As Single)
sta = (Val(base) ^ Val(bits)): den = den + 1: If sta < den Then MsgBox "ERROR!  Number exceeds bit/base setting values!": Exit Function
For b = Val(bits) To 1 Step -1
sta = sta / base
By = 0
For c = 1 To Val(base)
If den > sta Then den = den - sta: By = By + 1
Next c
x = x & Trim(Str(By))
Next b
den2bin = x
End Function

---

And the whole thing in a module you can test it with...attached.

If you enjoy, you know where my "reputation" link is :-P

Remember I have *NOT* optimized this in any way...it could be improved in a few ways

Here's something I whipped up. It doesn't support negative numbers, but it's rather nifty just the same.

Code:

---

Public Function AnyBase(ByVal Number As Long, ByVal Base As Long) As String
  Dim Ret As String
  Dim Digit As Long
 
  If Base < 2 Or Base > 36 Then
    MsgBox "Invalid base", vbOKOnly, "AnyBase"
    Exit Function
  End If
  If Number = 0 Then Ret = "0"
  Do While Number > 0
    Digit = Number Mod Base
    If Digit < 10 Then
      Ret = Chr$(48 + Digit) & Ret
    Else
      Ret = Chr$(55 + Digit) & Ret
    End If
    Number = Number \ Base
  Loop
  AnyBase = Ret
End Function

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Another binary to decimal (string manipulation rather than 2^n calculation).

http://www.vbforums.com/showthread.p...&highlight=hex