36 static constexpr char TRAN =
'N';
42 int solve_trs(Mat<T>&, Mat<T>&&);
55 BandMat(
const uword in_size,
const uword in_l,
const uword in_u)
56 :
DenseMat<
T>(in_size, in_size, (2 * in_l + in_u + 1) * in_size)
58 ,
m_rows(2 * in_l + in_u + 1)
62 suanpan_warning(
"The storage requirement for the banded matrix is larger than that of a full matrix, consider using a full/sparse matrix instead.\n");
65 unique_ptr<MetaMat<T>>
make_copy()
override {
return std::make_unique<BandMat>(*
this); }
73 T operator()(
const uword in_row,
const uword in_col)
const override {
74 if(in_row > in_col +
l_band || in_row +
u_band < in_col) [[unlikely]]
return bin =
T(0);
75 return this->
memory[in_row + s_band + in_col * (
m_rows - 1)];
78 T&
unsafe_at(
const uword in_row,
const uword in_col)
override {
80 return this->
memory[in_row + s_band + in_col * (
m_rows - 1)];
83 T&
at(
const uword in_row,
const uword in_col)
override {
84 if(in_row > in_col +
l_band || in_row +
u_band < in_col) [[unlikely]]
return bin =
T(0);
88 Mat<T>
operator*(
const Mat<T>&)
const override;
94 Mat<T> Y(arma::size(X));
96 const auto M =
static_cast<int>(this->n_rows);
97 const auto N =
static_cast<int>(this->n_cols);
98 const auto KL =
static_cast<int>(l_band);
99 const auto KU =
static_cast<int>(u_band);
100 const auto LDA =
static_cast<int>(m_rows);
101 constexpr auto INC = 1;
105 if constexpr(std::is_same_v<T, float>) {
107 suanpan::for_each(X.n_cols, [&](
const uword I) { arma_fortran(arma_sgbmv)(&TRAN, &M, &N, &KL, &KU, (E*)&ALPHA, (E*)(this->memptr() + l_band), &LDA, (E*)X.colptr(I), &INC, (E*)&BETA, (E*)Y.colptr(I), &INC); });
111 suanpan::for_each(X.n_cols, [&](
const uword I) { arma_fortran(arma_dgbmv)(&TRAN, &M, &N, &KL, &KU, (E*)&ALPHA, (E*)(this->memptr() + l_band), &LDA, (E*)X.colptr(I), &INC, (E*)&BETA, (E*)Y.colptr(I), &INC); });
118 if(this->factored)
return this->solve_trs(X, std::forward<Mat<T>>(B));
120 suanpan_assert([&] {
if(this->n_rows != this->n_cols)
throw invalid_argument(
"requires a square matrix"); });
124 auto N =
static_cast<int>(this->n_rows);
125 const auto KL =
static_cast<int>(l_band);
126 const auto KU =
static_cast<int>(u_band);
127 const auto NRHS =
static_cast<int>(B.n_cols);
128 const auto LDAB =
static_cast<int>(m_rows);
129 const auto LDB =
static_cast<int>(B.n_rows);
130 this->pivot.zeros(
N);
131 this->factored =
true;
133 if constexpr(std::is_same_v<T, float>) {
135 arma_fortran(arma_sgbsv)(&
N, &KL, &KU, &NRHS, (
E*)this->memptr(), &LDAB, this->pivot.memptr(), (
E*)B.memptr(), &LDB, &INFO);
140 arma_fortran(arma_dgbsv)(&
N, &KL, &KU, &NRHS, (
E*)this->memptr(), &LDAB, this->pivot.memptr(), (
E*)B.memptr(), &LDB, &INFO);
144 this->s_memory = this->to_float();
145 arma_fortran(arma_sgbtrf)(&
N, &
N, &KL, &KU, this->s_memory.memptr(), &LDAB, this->pivot.memptr(), &INFO);
146 if(0 == INFO) INFO = this->solve_trs(X, std::forward<Mat<T>>(B));
150 suanpan_error(
"Error code {} received, the matrix is probably singular.\n", INFO);
158 const auto N =
static_cast<int>(this->n_rows);
159 const auto KL =
static_cast<int>(l_band);
160 const auto KU =
static_cast<int>(u_band);
161 const auto NRHS =
static_cast<int>(B.n_cols);
162 const auto LDAB =
static_cast<int>(m_rows);
163 const auto LDB =
static_cast<int>(B.n_rows);
165 if constexpr(std::is_same_v<T, float>) {
167 arma_fortran(arma_sgbtrs)(&TRAN, &
N, &KL, &KU, &NRHS, (
E*)this->memptr(), &LDAB, this->pivot.memptr(), (
E*)B.memptr(), &LDB, &INFO);
172 arma_fortran(arma_dgbtrs)(&TRAN, &
N, &KL, &KU, &NRHS, (
E*)this->memptr(), &LDAB, this->pivot.memptr(), (
E*)B.memptr(), &LDB, &INFO);
176 this->mixed_trs(X, std::forward<Mat<T>>(B), [&](fmat& residual) {
177 arma_fortran(arma_sgbtrs)(&TRAN, &
N, &KL, &KU, &NRHS, this->s_memory.memptr(), &LDAB, this->pivot.memptr(), residual.memptr(), &LDB, &INFO);
182 suanpan_error(
"Error code {} received, the matrix is probably singular.\n", INFO);
A BandMat class that holds matrices.
Definition: BandMat.hpp:35
T & unsafe_at(const uword in_row, const uword in_col) override
Access element without bound check.
Definition: BandMat.hpp:78
BandMat(const uword in_size, const uword in_l, const uword in_u)
Definition: BandMat.hpp:55
T & at(const uword in_row, const uword in_col) override
Access element with bound check.
Definition: BandMat.hpp:83
const uword u_band
Definition: BandMat.hpp:48
unique_ptr< MetaMat< T > > make_copy() override
Definition: BandMat.hpp:65
T operator()(const uword in_row, const uword in_col) const override
Access element (read-only), returns zero if out-of-bound.
Definition: BandMat.hpp:73
const uword l_band
Definition: BandMat.hpp:47
const uword m_rows
Definition: BandMat.hpp:45
void nullify(const uword K) override
Definition: BandMat.hpp:67
A DenseMat class that holds matrices.
Definition: DenseMat.hpp:39
std::unique_ptr< T[]> memory
Definition: DenseMat.hpp:48
void for_each(const IT start, const IT end, F &&FN)
Definition: utility.h:28
#define suanpan_warning(...)
Definition: suanPan.h:308
void suanpan_assert(const std::function< void()> &F)
Definition: suanPan.h:296
#define suanpan_error(...)
Definition: suanPan.h:309