Developer Reference for Intel® oneAPI Math Kernel Library for C
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?dttrsb
Solves a system of linear equations with a diagonally dominant tridiagonal coefficient matrix using the LU factorization computed by ?dttrfb.
Syntax
void sdttrsb (const char * trans, const MKL_INT * n, const MKL_INT * nrhs, const float * dl, const float * d, const float * du, float * b, const MKL_INT * ldb, MKL_INT * info );
void ddttrsb (const char * trans, const MKL_INT * n, const MKL_INT * nrhs, const double * dl, const double * d, const double * du, double * b, const MKL_INT * ldb, MKL_INT * info );
void cdttrsb (const char * trans, const MKL_INT * n, const MKL_INT * nrhs, const MKL_Complex8 * dl, const MKL_Complex8 * d, const MKL_Complex8 * du, MKL_Complex8 * b, const MKL_INT * ldb, MKL_INT * info );
void zdttrsb (const char * trans, const MKL_INT * n, const MKL_INT * nrhs, const MKL_Complex16 * dl, const MKL_Complex16 * d, const MKL_Complex16 * du, MKL_Complex16 * b, const MKL_INT * ldb, MKL_INT * info );
Include Files
- mkl.h
 
Description
The ?dttrsb routine solves the following systems of linear equations with multiple right hand sides for X:
A*X = B  |  
      if trans='N',  |  
     
AT*X = B  |  
      if trans='T',  |  
     
AH*X = B  |  
      if trans='C' (for complex matrices only).  |  
     
Before calling this routine, call ?dttrfb to compute the factorization of A.
Input Parameters
trans  |  
      Must be 'N' or 'T' or 'C'. Indicates the form of the equations solved for X: If trans = 'N', then A*X = B. If trans = 'T', then AT*X = B. If trans = 'C', then AH*X = B.  |  
     
n  |  
      The order of A; n≥ 0.  |  
     
nrhs  |  
      The number of right-hand sides, that is, the number of columns in B; nrhs≥ 0.  |  
     
dl, d, du  |  
      Arrays: dl(n -1), d(n), du(n -1). The array dl contains the (n - 1) multipliers that define the matrices L1, L2 from the factorization of A. The array d contains the n diagonal elements of the upper triangular matrix U from the factorization of A. The array du contains the (n - 1) elements of the superdiagonal of U.  |  
     
b  |  
      Array of size max(1, ldb*nrhs). Contains the matrix B whose columns are the right-hand sides for the systems of equations.  |  
     
ldb  |  
      The leading dimension of b; ldb≥ max(1, n).  |  
     
Output Parameters
b  |  
      Overwritten by the solution matrix X.  |  
     
info  |  
      If info = 0, the execution is successful. If info = -i, the i-th parameter had an illegal value.  |