Make matrix::solve() work with non-normal zeros.

[ginac.git] / check / exam_matrices.cpp

diff --git a/check/exam_matrices.cpp b/check/exam_matrices.cpp
index 586c52f57673a0bc20a33e89ba152f01697e31f7..7770e6bf829beaaa3101b965bb57571d9e07242b 100644 (file)
--- a/check/exam_matrices.cpp
+++ b/check/exam_matrices.cpp
@@ -1,3 +1,4 @@
+
 /** @file exam_matrices.cpp
  *
  *  Here we examine manipulations on GiNaC's symbolic matrices. */
@@ -275,6 +276,35 @@ static unsigned matrix_rank()
        return result;  
 }
 
+unsigned matrix_solve_nonnormal()
+{
+       symbol a("a"), b("b"), c("c"), x("x");
+       // This matrix has a non-normal zero element!
+       matrix mx {{1,0,0},
+                  {0,1/(x+1)-(x-1)/(x*x-1),1},
+                  {0,0,0}};
+       matrix zero {{0}, {0}, {0}};
+       matrix vars {{a}, {b}, {c}};
+       try {
+               matrix sol_gauss   = mx.solve(vars, zero, solve_algo::gauss);
+               matrix sol_divfree = mx.solve(vars, zero, solve_algo::divfree);
+               matrix sol_bareiss = mx.solve(vars, zero, solve_algo::bareiss);
+               if (sol_gauss != sol_divfree  ||  sol_gauss != sol_bareiss) {
+                       clog << "different solutions while solving "
+                            << mx << " * " << vars << " == " << zero << endl
+                            << "gauss:   " << sol_gauss << endl
+                            << "divfree: " << sol_divfree << endl
+                            << "bareiss: " << sol_bareiss << endl;
+                       return 1;
+               }
+       } catch (const exception & e) {
+               clog << "exception thrown while solving "
+                    << mx << " * " << vars << " == " << zero << endl;
+               return 1;
+       }
+       return 0;
+}
+
 static unsigned matrix_misc()
 {
        unsigned result = 0;
@@ -337,6 +367,7 @@ unsigned exam_matrices()
        result += matrix_solve2();  cout << '.' << flush;
        result += matrix_evalm();  cout << "." << flush;
        result += matrix_rank();  cout << "." << flush;
+       result += matrix_solve_nonnormal();  cout << "." << flush;
        result += matrix_misc();  cout << '.' << flush;
        
        return result;