# zpotrs.f man page

zpotrs.f —

## Synopsis

### Functions/Subroutines

subroutinezpotrs(UPLO, N, NRHS, A, LDA, B, LDB, INFO)ZPOTRS

## Function/Subroutine Documentation

### subroutine zpotrs (characterUPLO, integerN, integerNRHS, complex*16, dimension( lda, * )A, integerLDA, complex*16, dimension( ldb, * )B, integerLDB, integerINFO)

**ZPOTRS**

**Purpose:**

```
ZPOTRS solves a system of linear equations A*X = B with a Hermitian
positive definite matrix A using the Cholesky factorization
A = U**H * U or A = L * L**H computed by ZPOTRF.
```

**Parameters:**

*UPLO*

```
UPLO is CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
```

*N*

```
N is INTEGER
The order of the matrix A. N >= 0.
```

*NRHS*

```
NRHS is INTEGER
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.
```

*A*

```
A is COMPLEX*16 array, dimension (LDA,N)
The triangular factor U or L from the Cholesky factorization
A = U**H * U or A = L * L**H, as computed by ZPOTRF.
```

*LDA*

```
LDA is INTEGER
The leading dimension of the array A. LDA >= max(1,N).
```

*B*

```
B is COMPLEX*16 array, dimension (LDB,NRHS)
On entry, the right hand side matrix B.
On exit, the solution matrix X.
```

*LDB*

```
LDB is INTEGER
The leading dimension of the array B. LDB >= max(1,N).
```

*INFO*

```
INFO is INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
```

**Author:**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

**Date:**

November 2011

Definition at line 111 of file zpotrs.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

zpotrs(3) is an alias of zpotrs.f(3).