Integer to boolean/bit array without looping - arrays

Question

I have a number (say 5) which I would first like to convert to binary (101) and then split into an array of bits {1,0,1} or Booleans {True,False,True} in VBA
Is there a way to do this without looping?
I can convert to Binary without looping in my code with the worksheet formula as follows
myBinaryNum = [DEC2BIN(myDecInteger,[places])]
But I've been told that worksheet functions are very inefficient, and this one is particularly limited.
I'm not sure how to split into an array without looping through the digits with MID. Is there anything like strConv for numbers?

Answer 1

You could first convert the value to a "01" string with WorksheetFunction.Dec2Bin.
Then replace each "0","1" with the code 0 or 1 and cast the result to a Byte array :
Public Function ToBitArray(ByVal value As Long) As Byte()
Dim str As String
str = WorksheetFunction.Dec2Bin(value) ' "101"
str = Replace(Replace(str, "0", ChrW(0)), "1", ChrW(1)) ' "\u0001\u0000\u0001"
ToBitArray = StrConv(str, vbFromUnicode) ' [1, 0, 1]
End Function
But Dec2Bin is limited to 511 and working with strings is rather expensive. So if your goal is to get the best performance, then you should use a loop to read each bit:
Public Function ToBitArray(ByVal value As Long) As Byte()
Dim arr(0 To 31) As Byte, i As Long
i = 32&
Do While value
i = i - 1
arr(i) = value And 1
value = value \ 2
Loop
ToBitArray = MidB(arr, i + 1) ' trim leading zeros
End Function

Answer 2

I found this neat code on another question here at SO. Basically, you can be sure your string is ASCII due to the fact it's 1's and 0's.
What you do is you use
Dim my_string As String
my_string = CStr("your binary number")
To turn your binary number into a string
And then
Dim buff() As String
buff = Split(StrConv(my_string, vbUnicode), Chr$(0))
ReDim Preserve buff(UBound(buff) - 1
To split that string into an array where buff is your array

Answer 3

I think you've probably got everything you need above from other answers, but if you want a simple function that takes the decimal and returns the array..
Function dec_to_binary_array(decNum As Integer)
Dim arr() As String, NumAsString As String
NumAsString = Application.Dec2Bin(decNum)
arr = Split(StrConv(NumAsString, vbUnicode), vbNullChar)
ReDim Preserve arr(UBound(arr) - 1)
dec_to_binary_array = arr
End Function

Answer 4

Invoking Application.Dec2Bin(n) isn't realy expensive, it only costs a late bound call. Use the function below to transform any integer into an arrays of bits:
Function Bits(n as long)
Dim s As String: s = Application.Dec2Bin(n)
Dim ar: ar = Split(StrConv(s, vbUnicode), vbNullChar)
Bits = ar
End Function
p.s.: s will only contain 0 and 1 which are ASCII characters, so the split technique is perfectly valid.

Answer 5

Function d2bin(dec As Integer, bits As Integer) As Integer()
Dim maxVal As Integer
maxVal = 2 ^ (bits)-1
If dec > maxVal Then Exit Function
Dim i As Integer
Dim result() As Integer
ReDim result(0 To bits - 1)
For i = bits - 1 To 0 Step -1
result(bits - i - 1) = -(dec > (2 ^ (i) - 1))
If result(bits - i - 1) Then dec = dec - (2 ^ i)
Next i
d2bin = result
End Function

Answer 6

Please check this code if this is what you need:
You can replace the the digit 5 by any cell value reference, this is just and example:
Sub dectobinary()
Dim BinaryString As String
BinaryString = "5"
tempval = Dec2Bin(BinaryString)
MsgBox tempval
End Sub
Function Dec2Bin(ByVal DecimalIn As Variant) As String
Dec2Bin = ""
DecimalIn = Int(CDec(DecimalIn))
Do While DecimalIn <> 0
Dec2BinTemp = Format$(DecimalIn - 2 * Int(DecimalIn / 2))
If Dec2BinTemp = "1" Then
Dec2Bin = "True" & "," & Dec2Bin
Else
Dec2Bin = "False" & "," & Dec2Bin
End If
DecimalIn = Int(DecimalIn / 2)
Loop
End Function

Answer 7

Just change lngNumber value to your desired number
Public Sub sChangeNumberToBinaryArray()
Dim strBinaryNumber As String
Dim strBinaryArray() As String
Dim lngNumber As Long
lngNumber = 5
strBinaryNumber = DecToBin(lngNumber)
strBinaryArray() = Split(strBinaryNumber, "|")
End Sub
Function DecToBin(ByVal varDecimalIn As Variant) As String
Dim lngCounter As Long
DecToBin = ""
varDecimalIn = Int(CDec(varDecimalIn))
lngCounter = 1
Do While varDecimalIn <> 0
If lngCounter = 1 Then
DecToBin = Format$(varDecimalIn - 2 * Int(varDecimalIn / 2)) & DecToBin
lngCounter = lngCounter + 1
Else
DecToBin = Format$(varDecimalIn - 2 * Int(varDecimalIn / 2)) & "|" & DecToBin
lngCounter = lngCounter + 1
End If
varDecimalIn = Int(varDecimalIn / 2)
Loop
End Function