invocation history stack overflow



Hi,

When calculating the eigenvectors of the following transition rate
matrix, I encountered the error mentioned in the subject (using
imaxima from Emacs).  Running maxima from the command line looks like
this:

(%i1) Q: matrix([-(lee+leu+len), lee, leu, len], [0,-(leu+len),leu,len], [0,lue,-(lue+lun),lun], [0,lne,lnu,-(lne+lnu)]);
         [ - leu - len - lee      lee          leu          len     ]
         [                                                          ]
         [         0          - leu - len      leu          len     ]
(%o1)    [                                                          ]
         [         0              lue      - lun - lue      lun     ]
         [                                                          ]
         [         0              lne          lnu      - lnu - lne ]
(%i2) eigenvalues(Q);
                   2                                                    2
(%o2) [[- (sqrt(lun  + (2 lue + 2 lnu - 2 lne - 2 leu - 2 len) lun + lue
                                              2
 + (- 2 lnu - 2 lne + 2 leu - 2 len) lue + lnu  + (2 lne - 2 leu - 2 len) lnu
      2                            2                  2
 + lne  + (2 len - 2 leu) lne + leu  + 2 len leu + len ) + lun + lue + lnu
                                2
 + lne + leu + len)/2, (sqrt(lun  + (2 lue + 2 lnu - 2 lne - 2 leu - 2 len) lun
      2                                              2
 + lue  + (- 2 lnu - 2 lne + 2 leu - 2 len) lue + lnu
                                    2                            2
 + (2 lne - 2 leu - 2 len) lnu + lne  + (2 len - 2 leu) lne + leu  + 2 len leu
      2
 + len ) - lun - lue - lnu - lne - leu - len)/2, - leu - len - lee, 0], 
[1, 1, 1, 1]]
(%i3) eigenvectors(Q);

Maxima encountered a Lisp error:

 Error in CONDITIONS::CLCS-UNIVERSAL-ERROR-HANDLER [or a callee]: Couldn't protect

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