void scalarMultInPlace(DMat<RT>& A, const typename RT::ElementType &f)
{
for (size_t i=0; i<A.numRows()*A.numColumns(); i++)
{
A.ring().mult(A.array()[i], f, A.array()[i]);
}
}
bool isZero(const DMat<RT>& A)
{
size_t len = A.numRows() * A.numColumns();
if (len == 0) return true;
for (auto t = A.array() + len - 1; t >= A.array(); t--)
if (!A.ring().is_zero(*t)) return false;
return true;
}
void negateInPlace(DMat<RT>& A)
// A = -A
{
size_t len = A.numRows() * A.numColumns();
for (size_t i=0; i<len; i++)
{
A.ring().negate(A.array()[i], A.array()[i]);
}
}
bool isEqual(const DMat<RT>& A, const DMat<RT>& B)
{
assert(&A.ring() == &B.ring());
if (B.numRows() != A.numRows()) return false;
if (B.numColumns() != A.numColumns()) return false;
size_t top = A.numRows() * A.numColumns();
auto elemsA = A.array();
auto elemsB = B.array();
for (size_t i = 0; i < top; i++)
if (!A.ring().is_equal(*elemsA++, *elemsB++)) return false;
return true;
}
void subtractInPlace(DMat<RT>& A, const DMat<RT>& B)
// A -= B
{
M2_ASSERT(&B.ring() == &A.ring());
M2_ASSERT(B.numRows() == A.numRows());
M2_ASSERT(B.numColumns() == A.numColumns());
size_t len = A.numRows() * A.numColumns();
for (size_t i=0; i<len; i++)
{
A.ring().subtract(A.array()[i], A.array()[i], B.array()[i]);
}
}
void addInPlace(DMat<RT>& A, const DMat<RT>& B)
// A += B.
{
assert(&B.ring() == &A.ring());
assert(B.numRows() == A.numRows());
assert(B.numColumns() == A.numColumns());
size_t len = A.numRows() * A.numColumns();
for (size_t i = 0; i < len; i++)
{
A.ring().add(A.array()[i], A.array()[i], B.array()[i]);
}
}
void subtractMultipleTo(DMat<RT>& C,
const DMat<RT>& A,
const DMat<RT>& B)
// C = C - A*B
{
typedef typename RT::ElementType ElementType;
typedef typename DMat<RT>::ConstIterator ConstIterator;
M2_ASSERT(A.numColumns() == B.numRows());
M2_ASSERT(A.numRows() == C.numRows());
M2_ASSERT(B.numColumns() == C.numColumns());
ElementType* result = C.array();
ElementType tmp;
A.ring().init(tmp);
// WARNING: this routine expects the result matrix to be in ROW MAJOR ORDER
for (size_t i = 0; i<A.numRows(); i++)
for (size_t j = 0; j<B.numColumns(); j++)
{
ConstIterator i1 = A.rowBegin(i);
ConstIterator iend = A.rowEnd(i);
ConstIterator j1 = B.columnBegin(j);
while (i1 != iend)
{
A.ring().mult(tmp, *i1, *j1);
A.ring().subtract(*result, *result, tmp);
++i1;
++j1;
}
result++;
}
A.ring().clear(tmp);
}
void mult(const DMat<RT>& A,
const DMat<RT>& B,
DMat<RT>& result_product)
{
//printf("entering dmat mult\n");
typedef typename RT::ElementType ElementType;
typedef typename DMat<RT>::ConstIterator ConstIterator;
M2_ASSERT(A.numColumns() == B.numRows());
M2_ASSERT(A.numRows() == result_product.numRows());
M2_ASSERT(B.numColumns() == result_product.numColumns());
ElementType* result = result_product.array();
ElementType tmp;
A.ring().init(tmp);
// WARNING: this routine expects the result matrix to be in ROW MAJOR ORDER
for (size_t i = 0; i<A.numRows(); i++)
for (size_t j = 0; j<B.numColumns(); j++)
{
ConstIterator i1 = A.rowBegin(i);
ConstIterator iend = A.rowEnd(i);
ConstIterator j1 = B.columnBegin(j);
while (i1 != iend)
{
A.ring().mult(tmp, *i1, *j1);
A.ring().add(*result, *result, tmp);
++i1;
++j1;
}
result++;
}
A.ring().clear(tmp);
}
engine_RawArrayIntPairOrNull rawLQUPFactorizationInPlace(MutableMatrix *A, M2_bool transpose)
{
#ifdef HAVE_FFLAS_FFPACK
// Suppose A is m x n
// then we get A = LQUP = LSP, see e.g. http://www.ens-lyon.fr/LIP/Pub/Rapports/RR/RR2006/RR2006-28.pdf
// P and Q are permutation info using LAPACK's convention:, see
// http://www.netlib.org/lapack/explore-html/d0/d39/_v_a_r_i_a_n_t_s_2lu_2_r_e_c_2dgetrf_8f.html
// P is n element permutation on column: size(P)=min(m,n);
// for 1 <= i <= min(m,n), col i of the matrix was interchanged with col P(i).
// Qt is m element permutation on rows (inverse permutation)
// for 1 <= i <= min(m,n), col i of the matrix was interchanged with col P(i).
A->transpose();
DMat<M2::ARingZZpFFPACK> *mat = A->coerce< DMat<M2::ARingZZpFFPACK> >();
if (mat == 0)
{
throw exc::engine_error("LUDivine not defined for this ring");
// ERROR("LUDivine not defined for this ring");
// return 0;
}
size_t nelems = mat->numColumns();
if (mat->numRows() < mat->numColumns()) nelems = mat->numRows();
std::vector<size_t> P(nelems, -1);
std::vector<size_t> Qt(nelems, -1);
// ignore return value (rank) of:
LUdivine(mat->ring().field(),
FFLAS::FflasNonUnit,
(transpose ? FFLAS::FflasTrans : FFLAS::FflasNoTrans),
mat->numRows(),
mat->numColumns(),
mat->array(),
mat->numColumns(),
&P[0],
&Qt[0]);
engine_RawArrayIntPairOrNull result = new engine_RawArrayIntPair_struct;
result->a = stdvector_to_M2_arrayint(Qt);
result->b = stdvector_to_M2_arrayint(P);
return result;
#endif
return 0;
}