private static void CheckFactorization(SkylineMatrix originalMatrix, int expectedNullity, double tolerance)
{
var factorization = originalMatrix.FactorSemidefiniteLdl(false, tolerance);
Assert.True(factorization.DependentColumns.Count == expectedNullity,
$"Nullity = {factorization.DependentColumns.Count} != {expectedNullity} (expected)");
SemidefiniteCholeskyFullTests.CheckNullSpace(originalMatrix, factorization.NullSpaceBasis, tolerance);
}