[Maxima-discuss] Cannot convert expression into C code. Bug in allgentran?

[Ivan <ast...@bk...>]

Hi all,

I cannot convert a long enough expression into C code with gentran. Is 
it bug or I'm missing something?

Also, is there any other way to generate C code?

The expression that cannot be converted is

var:-((sqrt(m_piM^4+W^8*cost^2-W^8+4*P0^2*W^6)+((cost^2-1)*m_nuc^2+W^2*cost^2-W^2)*m_piM^4+sqrt(m_piM^2+P0^2)*(4*W^2*m_nuc*m_piM^2-4*W^2*m_nuc^3+4*W^4*m_nuc)+((2-2*cost^2)*m_nuc^4-4*W^2*cost^2*m_nuc^2-2*W^4*cost^2-2*W^4)*m_piM^2+(cost^2-1)*m_nuc^6+(W^2-W^2*cost^2)*m_nuc^4+(W^4-W^4*cost^2)*m_nuc^2+W^6*cost^2-W^6)/((cost^2-1)*m_piM^4+((2-2*cost^2)*m_nuc^2-2*W^2*cost^2-2*W^2)*m_piM^2+(cost^2-1)*m_nuc^4+(2*W^2-2*W^2*cost^2)*m_nuc^2+W^4*cost^2-W^4));

Here is full example:


$ maxima
Loading /home/larry/.maxima/maxima-init.mac
Maxima 5.48.1 https://maxima.sourceforge.io
using Lisp SBCL 2.5.4
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) load(allgentran);
(%o1)  /usr/share/maxima/5.48.1/share/contrib/gentran/allgentran.lisp
(%i2) gentranlang:c;
(%o2)                                  c
(%i3) 
var:-((sqrt(m_piM^4+W^8*cost^2-W^8+4*P0^2*W^6)+((cost^2-1)*m_nuc^2+W^2*cost^2-W^2)*m_piM^4+sqrt(m_piM^2+P0^2)*(4*W^2*m_nuc*m_piM^2-4*W^2*m_nuc^3+4*W^4*m_nuc)+((2-2*cost^2)*m_nuc^4-4*W^2*cost^2*m_nuc^2-2*W^4*cost^2-2*W^4)*m_piM^2+(cost^2-1)*m_nuc^6+(W^2-W^2*cost^2)*m_nuc^4+(W^4-W^4*cost^2)*m_nuc^2+W^6*cost^2-W^6)/((cost^2-1)*m_piM^4+((2-2*cost^2)*m_nuc^2-2*W^2*cost^2-2*W^2)*m_piM^2+(cost^2-1)*m_nuc^4+(2*W^2-2*W^2*cost^2)*m_nuc^2+W^4*cost^2-W^4));
                    4    8     2    8       2  6
(%o3) - (sqrt(m_piM  + W  cost  - W  + 4 P0  W )
          2           2    2     2    2       4
  + ((cost  - 1) m_nuc  + W  cost  - W ) m_piM
              2     2      2            2      2      3      4
  + sqrt(m_piM  + P0 ) (4 W  m_nuc m_piM  - 4 W  m_nuc  + 4 W m_nuc)
                2       4      2     2      2      4     2      4      2
  + ((2 - 2 cost ) m_nuc  - 4 W  cost  m_nuc  - 2 W  cost  - 2 W ) m_piM
         2           6     2    2     2       4     4    4     2    2
  + (cost  - 1) m_nuc  + (W  - W  cost ) m_nuc  + (W  - W  cost ) m_nuc
     6     2    6        2           4               2       2 2     2
  + W  cost  - W )/((cost  - 1) m_piM  + ((2 - 2 cost ) m_nuc  - 2 W  cost
       2       2        2           4       2      2     2       2   4     2
  - 2 W ) m_piM  + (cost  - 1) m_nuc  + (2 W  - 2 W  cost ) m_nuc + W  cost
     4
  - W )
(%i4) gentran(eval(var));

Maxima encountered a Lisp error:

  LEFTOVER-MFORMAT-ARGS?: extra mformat args (NIL T0 undeclared variable 
NIL)

Automatically continuing.
To enable the Lisp debugger set *debugger-hook* to nil.