triangularize behaving unexpectedly



>>>>> "Fred" == Fred J  writes:

    Fred> Hello
    Fred> triangularize () is behaving unexpectedly.
    Fred>  A:matrix([0,1,2],[-1,0,3],[-2,-3,0]);
    Fred> (%i2) triangularize(A);

    Fred> 			       [ - 1   0    3  ]
    Fred> 			       [	       ]
    Fred> (%o2) 			       [  0   - 1  - 2 ]
    Fred> 			       [	       ]
    Fred> 			       [  0    0    0  ]
    Fred> well, this is not the upper triangular form of the
    Fred> matrix `A'. am I missing something?

Define what you mean by upper triangular form.  The result appears to
be obtained from performing elementary row operations on A, and is a
triangular matrix.

This issue was discussed at length in bug 1064238 "triangularize gives
wrong results."
(http://sourceforge.net/tracker/?group_id=4933&atid=104933&func=detail&aid=1064238)

Ray