little Binary Help

Hi to all,
I can do some lisp, but not when it comes to binary.
Would someone be kind enough to make me a lisp that
could transpose binary digits into an ascii letter?
This is how I would like it......
If for arguements sake I had a binary notation like this:
" 00101010 " of which equals T I would like to be able
to offer the notion to the lisp and have its resulting ascii equivilent
shown to screen (or just returned ).

Is this possible?

thank you

regards Jane

 

Hi Jane

This function shold do what you want:

Code:

;
; -- Function MeBinary2Dec
; Convert Binary to a decimal number.
; Arguments [Type]:
;   Bin = Binary data, eg. 11101 [STR]
;   Msd = Most significant digit [SYM] *)
; Return [Type]:
;   > Decimal number [INT]
; Notes:
;   *) If true first digit is MSD, else last digit
;
(defun MeBinary2Dec (Bin Msd / CurBit ExpCnt RetVal StrCnt)
(setq StrCnt (if Msd (strlen Bin) 1)
ExpCnt 0
RetVal 0
)
(repeat (strlen Bin)
(setq CurBit (atoi (substr Bin StrCnt 1))
RetVal (+ (* CurBit (expt 2 ExpCnt)) RetVal)
StrCnt (if Msd (1- StrCnt) (1+ StrCnt))
ExpCnt (1+ ExpCnt)
)
)
RetVal
)

Sample:
(chr (MeBinary2Dec "00101010" nil))
"T"

Cheers

 

Wow, thanks for being so quick Jurg.

Um, I'm having a problem with it though, it seems you have
two globals and I dont quite understand the second.
I have just offered the lisp to autocad and this is what I got back:
**AutoCAD menu utilities loaded.
AutoCAD Express Tools Menu loaded.
Command: (load "bin")
; error: no function definition: MEBINARY2DEC

Command: (mebinary2dec 00101010)
; error: no function definition: MEBINARY2DEC

Command: (mebinary2dec 01010100)
; error: no function definition: MEBINARY2DEC**

I even tried it by reversing the binary notation for the letter T in
case it wasnt reading from right to left, (or is that left to right?)

Is there a lisp where I can just put in the binary alone to receive
the ascii equivalent?

regards Jane

 

Oops, was a bit to theoretically...

Doesn't affect the result but it's more elegant if you change the line:
RetVal (+ (* CurBit (expt 2 ExpCnt)) RetVal)
to
RetVal (+ (lsh CurBit ExpCnt) RetVal)

Cheers

 

Hmmm, now I am lost.
I had a hunch making binary to ascii would be hard, I just
didnt want to have to transpose it the old fashioned way by
doing it manually counting off.

regards Jane

 

Hi Jane

Is 'Bin' the file name where you saved the function (bin.lsp)?
The function requires 2 arguments:
- Binary value as string, eg. "00101010"
- MSD (most significant digit) as symbol, eg, T or nil
T=MSD is right, nil=MSD is left
Samples:
(MeBinary2Dec "00101010" nil) returns 84
(MeBinary2Dec "00101010" T) returns 42
With the lisp function 'chr' you can convert the decimal number to a
character string.

Cheers

 

YES, Excellent..!
Thank you.... it works just fine
Also, thank you for a promptness that I certainly
didnt expect.

regards Jane.

 

Hi Jurg,,,,,,,,,
I thought I had already sent a post saying::::
YES YES YES, that is Exactly what I wanted, but I cant
see it in my Sent Folder and it hasnt shown up here.
I sent it 30seconds after you sent the Attachment.......
So, in case it is out there somewhere in the ether, I will proffer my
elation again.............. Thank you Thank you Thank you.
It works just fine.

regards Jane

 

Hi Jane

Happy to help where I can. You're welcome...¦-)

Cheers

 

You is one clever cookie,,,,,
thanks jurg

regards Jane