p?dtsv
p?dtsv
Solves a general tridiagonal system of linear equations.
Syntax
void
psdtsv
(
MKL_INT
*n
,
MKL_INT
*nrhs
,
float
*dl
,
float
*d
,
float
*du
,
MKL_INT
*ja
,
MKL_INT
*desca
,
float
*b
,
MKL_INT
*ib
,
MKL_INT
*descb
,
float
*work
,
MKL_INT
*lwork
,
MKL_INT
*info
);
void
pddtsv
(
MKL_INT
*n
,
MKL_INT
*nrhs
,
double
*dl
,
double
*d
,
double
*du
,
MKL_INT
*ja
,
MKL_INT
*desca
,
double
*b
,
MKL_INT
*ib
,
MKL_INT
*descb
,
double
*work
,
MKL_INT
*lwork
,
MKL_INT
*info
);
void
pcdtsv
(
MKL_INT
*n
,
MKL_INT
*nrhs
,
MKL_Complex8
*dl
,
MKL_Complex8
*d
,
MKL_Complex8
*du
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_Complex8
*b
,
MKL_INT
*ib
,
MKL_INT
*descb
,
MKL_Complex8
*work
,
MKL_INT
*lwork
,
MKL_INT
*info
);
void
pzdtsv
(
MKL_INT
*n
,
MKL_INT
*nrhs
,
MKL_Complex16
*dl
,
MKL_Complex16
*d
,
MKL_Complex16
*du
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_Complex16
*b
,
MKL_INT
*ib
,
MKL_INT
*descb
,
MKL_Complex16
*work
,
MKL_INT
*lwork
,
MKL_INT
*info
);
Include Files
- mkl_scalapack.h
Description
The
function
solves a system of linear equations A
(1:n
, ja
:ja
+n
-1) * X
= B
(ib
:ib
+n
-1, 1:nrhs
)where is an
A
(1:n
, ja
:ja
+n
-1)n
-by-n
complex tridiagonal diagonally dominant-like distributed matrix.Gaussian elimination without pivoting is used to factor a reordering of the matrix into
L U
. Optimization Notice
|
|---|
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.
Notice revision #20110804
|
This notice covers the following instruction sets: SSE2, SSE4.2, AVX2, AVX-512.
Input Parameters
- n
- (global) The order of the distributed submatrixA(.n≥0)
- nrhs
- The number of right hand sides; the number of columns of the distributed matrixB(.nrhs≥0)
- dl
- (local).Pointer to local part of global vector storing the lower diagonal of the matrix. Globally,dl[0]is not referenced, anddlmust be aligned withd. Must be of size >desca[.nb_ - 1]
- d
- (local).Pointer to local part of global vector storing the main diagonal of the matrix.
- du
- (local).Pointer to local part of global vector storing the upper diagonal of the matrix. Globally,du[is not referenced, andn- 1]dumust be aligned withd.
- ja
- (global) The index in the global matrixAindicating the start of the matrix to be operated on (which may be either all ofAor a submatrix ofA).
- desca
- (global and local) array of sizedlen.If1,dtype (dtype_a=501 or 502);dlen≥ 7If2,dtype (dtype_a=1).dlen≥ 9The array descriptor for the distributed matrixA.Contains information of mapping ofAto memory.
- b
- (local)Pointer into the local memory to an array of local lead size. On entry, this array contains the local pieces of the right hand sideslld_b>nb.B(ib:ib+n-1, 1:nrhs)
- ib
- (global) The row index in the global matrixBindicating the first row of the matrix to be operated on (which may be either all ofbor a submatrix ofB).
- descb
- (global and local) array of sizedlen.If1,dtype (dtype_b=502);dlen≥ 7If2,dtype (dtype_b=1).dlen≥ 9The array descriptor for the distributed matrixB.Contains information of mapping ofBto memory.
- work
- (local).
- lwork
- (local or global) Size of user-input workspacework. Iflworkis too small, the minimal acceptable size will be returned inwork[0]and an error code is returned.lwork> (12*NPCOL+3*nb)+max((10+2*min(100,nrhs))*NPCOL+4*nrhs, 8*NPCOL)
Output Parameters
- dl
- On exit, this array contains information containing the * factors of the matrix.
- d
- On exit, this array contains information containing the * factors of the matrix. Must be of size>.desca[nb_ - 1]
- du
- On exit, this array contains information containing the * factors of the matrix. Must be of size>.desca[nb_ - 1]
- b
- On exit, this contains the local piece of the solutions distributed matrixX.
- work
- On exit,work[0]contains the minimallwork.
- info
- (local) If, the execution is successful.info=0< 0: If thei-th argument is an array and thej-entry had an illegal value, then, if theinfo= -(i*100+j)i-th argument is a scalar and had an illegal value, then.info= -i> 0: If, the submatrix stored on processorinfo=k<NPROCSinfoand factored locally was not positive definite, and the factorization was not completed.If, the submatrix stored on processorinfo=k>NPROCSrepresenting interactions with other processors was not positive definite, and the factorization was not completed.info-NPROCS