From bug-request at octave dot org Tue Jan  4 22:47:12 2005
Subject: Re: dec2base
From: Paul Kienzle <pkienzle at users dot sourceforge dot net>
To: Yassine Boujelben <yassine dot boujelben at polymtl dot ca>
Cc: bug-octave at bevo dot che dot wisc dot edu
Date: Tue, 4 Jan 2005 23:49:45 -0500


--Apple-Mail-4--108149933
Content-Transfer-Encoding: 7bit
Content-Type: text/plain;
	charset=US-ASCII;
	format=flowed

On Jan 3, 2005, at 3:58 PM, Yassine Boujelben wrote:

> I found the following bug in the dec2base function:
> dec2base(1000,10)=000

Try the attached patch.

Paul Kienzle <pkienzle at users dot sf dot net>
	* strings/dec2base.m: Use integer arithmetic to count number of digits.



--Apple-Mail-4--108149933
Content-Transfer-Encoding: 7bit
Content-Type: application/octet-stream;
	x-unix-mode=0644;
	name="dec2base.patch"
Content-Disposition: attachment;
	filename=dec2base.patch

Index: dec2base.m
===================================================================
RCS file: /cvs/octave/scripts/strings/dec2base.m,v
retrieving revision 1.4
diff -c -p -r1.4 dec2base.m
*** a/dec2base.m	29 Aug 2003 17:09:38 -0000	1.4
--- b/dec2base.m	5 Jan 2005 04:44:29 -0000
*************** function retval = dec2base (n, base, len
*** 74,80 ****
    endif
    
    ## determine number of digits required to handle all numbers
!   max_len = floor (log (max (max (n), 1)) ./ log (base)) + 1;
  
    if (nargin == 3)
      max_len = max (max_len, len);
--- 74,82 ----
    endif
    
    ## determine number of digits required to handle all numbers
!   max_n = max(max(n),1);
!   max_len = ceil(log(max_n)/log(base));
!   if (base^max_len <= max_n) max_len++; endif
  
    if (nargin == 3)
      max_len = max (max_len, len);
*************** function retval = dec2base (n, base, len
*** 89,91 ****
--- 91,119 ----
    retval = reshape (symbols (digits+1), size (digits));
  
  endfunction
+ 
+ %!test
+ %! s0='';
+ %! for n=1:13
+ %!   for b=2:16
+ %!     pp=dec2base(b^n+1,b);
+ %!     assert(dec2base(b^n,b),['1',s0,'0']);
+ %!     assert(dec2base(b^n+1,b),['1',s0,'1']);
+ %!   end
+ %!   s0=[s0,'0'];
+ %! end
+ 
+ %!test
+ %! digits='0123456789ABCDEF';
+ %! for n=1:13
+ %!   for b=2:16
+ %!     pm=dec2base(b^n-1,b);
+ %!     assert(length(pm),n);
+ %!     assert(all(pm==digits(b)));
+ %!   end
+ %! end
+ 
+ %!test
+ %! for b=2:16
+ %!   assert(dec2base(0,b),'0');
+ %! end

--Apple-Mail-4--108149933
Content-Transfer-Encoding: 7bit
Content-Type: text/plain;
	charset=US-ASCII;
	format=flowed




--Apple-Mail-4--108149933--



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------