Re: Strange results

[WJ]

Dwaddle wrote:

> Hi
> 
> i've been dabbling around in elisp for a while. Made this function
> 
> The issue is the byte var which 'remembers' the result from a previous 
> calculation.
> 
> (integer-bin 5)     [0 0 0 0 0 1 0 1]
> (integer-bin 3)     [0 0 0 0 0 1 1 1]
> 
> To beat the critics I know it isn't very clean programmed and a loop would 
> make it al lot shorter
> 
> <code>
> (defun integer-bin (dec)
>   "Convert integer to binairy"
>   (setq 8bit [128 64 32 16 8 4 2 1])
>   (setq byte [0 0 0 0 0 0 0 0])
>   (if (= 1 (/ dec (aref 8bit 0))) (when
>                                       (aset byte 0 1)
>                                       (setq dec (- dec 128))))
>   (if (< 0 dec)
>   (if (= 1 (/ dec (aref 8bit 1))) (when
>                                       (aset byte 1 1)
>                                       (setq dec (- dec 64)))))
>   (if (< 0 dec)
>   (if (= 1 (/ dec (aref 8bit 2))) (when
>                                       (aset byte 2 1)
>                                       (setq dec (- dec 32)))))
>   (if (< 0 dec)
>   (if (= 1 (/ dec (aref 8bit 3))) (when
>                                       (aset byte 3 1)
>                                       (setq dec (- dec 16)))))
>   (if (< 0 dec)
>   (if (= 1 (/ dec (aref 8bit 4))) (when
>                                       (aset byte 4 1)
>                                       (setq dec (- dec 8)))))
>   (if (< 0 dec)
>   (if (= 1 (/ d<ec (aref 8bit 5))) (when
>                                       (aset byte 5 1)
>                                       (setq dec (- dec 4)))))
>   (if (< 0 dec)
>   (if (= 1 (/ dec (aref 8bit 6))) (when
>                                       (aset byte 6 1)
>                                       (setq dec (- dec 2)))))
>  (if (< 0 dec)
>   (if (= 1 1) (when (aset byte 7 1)
>                     (setq dec (- dec 1)))))
>  (print byte)
> )
> </code> 

(defun integer->bin (byte)
  (let (result)
    (dotimes (_ 8)
      (push (logand byte 1) result)
      (setq byte (lsh byte -1)))
    result))