#3046 Changes of behaviour with simp:false

[Chris Sangwin]

I've complied Maxima 5.37.3 on Debian from source with no problems. Thank you for this.

The STACK project has failing unit tests caused by a change in the behaviour of Maxima with simp:false as follows. A minimal example is below.

The old version is

Maxima 5.36.1 http://maxima.sourceforge.net
using Lisp CLISP 2.49 (2010-07-07)
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) display2d:false;
(%o1) false
(%i2) simp:false;
(%o2) false
(%i3) (3/6)*x;
(%o3) (3/6)*x
(%i4)

The new version gives

Maxima 5.37.3 http://maxima.sourceforge.net
using Lisp CLISP 2.49 (2010-07-07)
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) display2d:false;
(%o1) false
(%i2) simp:false;
(%o2) false
(%i3) (3/6)*x;
(%o3) (3*x)/6

So, with simp:false we have a change of behaviour of

(3/6)*x -> (3*x)/6

This matters because I want to filter out coefficients in polynomials and rational numbers in other expressions and decide if a student has entered numbers in "lowest terms". I know this is a very subtle change, but it breaks the "lowest terms" test. Can anything be done about this?

Thanks,
Chris

[Robert Dodier]

I think I see how to fix up NFORMAT. Chris, can you send me your unit tests? I will include them in the Maxima test collection.

[Robert Dodier]

Fixed by commit 1a3bfbd. Closing this report.