On Wed, Mar 2, 2011 at 1:22 PM, Stavros Macrakis <macrakis at alum.mit.edu> wrote:
> No problem in Maxima 5.21.1 on GCL 2.6.8. (see below) ?Maybe garbage
> collector bugs in ECL and SBCL? -- but why would two independent
> implementations have this strange bug?
> BTW, are ECL and CLISP really that much slower than GCL, or are you using
> slow computers??Mine is an E8400 chip (3 years old, 3GHz). ?Not that speed
> matters much for Maxima in the common usage scenarios.
> ?? ? ? ? ? ? ? ? ?-s
>
> Maxima 5.21.1 http://maxima.sourceforge.net
> using Lisp GNU Common Lisp (GCL) GCL 2.6.8 (a.k.a. GCL)
> Distributed under the GNU Public License. See the file COPYING.
> Dedicated to the memory of William Schelter.
> The function bug_report() provides bug reporting information.
> (%i1) assume(y>1);
> while true do block([t,I,j],
> ?t: absolute_real_time(),
> ?for j: 1 step 1 thru 100 do I: integrate(log(x^2+y^2),x,0,1),
> ?print(absolute_real_time()-t));
> (%o1) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?[y > 1]
> (%i2)
> 4
> 4
> 3
This is more likely a regression in maxima. I get very different
results with maxima 5.20 (ccl 1.4) and 5.23 (ccl 1.7-svn) on the same
computer.
Andrej
------------------------------------------------------------
(%i1) assume(y>1);
while true do block([t,I,j],
t: absolute_real_time(),
for j: 1 step 1 thru 100 do I: integrate(log(x^2+y^2),x,0,1),
print(absolute_real_time()-t));
(%o1) [y>1]
7
7
7
8
7
7
7
7
7
7
8
7
7
7
interrupt
-- an error. To debug this try: debugmode(true);
(%i3) build_info();
Maxima version: 5.20.0
Maxima build date: 1:1 12/13/2009
Host type: i686-pc-mingw32
Lisp implementation type: Clozure Common Lisp
Lisp implementation version: Version 1.4-r13122 (WindowsX8632)
------------------------------------------------------------
(%i1) assume(y>1);
while true do block([t,I,j],
t: absolute_real_time(),
for j: 1 step 1 thru 100 do I: integrate(log(x^2+y^2),x,0,1),
print(absolute_real_time()-t));
(%o1) [y>1]
15
22
30
37
45
52
Maxima encountered a Lisp error:
interrupt signal
Automatically continuing.
To enable the Lisp debugger set *debugger-hook* to nil.
(%i3) build_info();
Maxima version: 5.23.2
Maxima build date: 20:27 2/27/2011
Host type: i686-pc-mingw32
Lisp implementation type: Clozure Common Lisp
Lisp implementation version: Version 1.7-dev-r14645M-trunk (WindowsX8632)
(%o3)