- SUBROUTINE CGETRS(
- TRANS, N, NRHS, A, LDA, IPIV, B, LDB, INFO )
- CHARACTER TRANS
- INTEGER INFO, LDA, LDB, N, NRHS
- INTEGER IPIV( * )
- COMPLEX A( LDA, * ), B( LDB, * )
PURPOSECGETRS solves a system of linear equations
A * X = B, A**T * X = B, or A**H * X = B with a general N-by-N matrix A using the LU factorization computed by CGETRF.
- TRANS (input) CHARACTER*1
Specifies the form of the system of equations:
= 'N': A * X = B (No transpose)
= 'T': A**T * X = B (Transpose)
= 'C': A**H * X = B (Conjugate transpose)
- N (input) INTEGER
- The order of the matrix A. N >= 0.
- NRHS (input) INTEGER
- The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
- A (input) COMPLEX array, dimension (LDA,N)
- The factors L and U from the factorization A = P*L*U as computed by CGETRF.
- LDA (input) INTEGER
- The leading dimension of the array A. LDA >= max(1,N).
- IPIV (input) INTEGER array, dimension (N)
- The pivot indices from CGETRF; for 1<=i<=N, row i of the matrix was interchanged with row IPIV(i).
- B (input/output) COMPLEX array, dimension (LDB,NRHS)
- On entry, the right hand side matrix B. On exit, the solution matrix X.
- LDB (input) INTEGER
- The leading dimension of the array B. LDB >= max(1,N).
- INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value