·  Home
+   man pages
 -> Linux -> FreeBSD -> OpenBSD -> NetBSD -> Tru64 Unix -> HP-UX 11i -> IRIX
·  Linux HOWTOs
·  FreeBSD Tips
·  *niX Forums

man pages->IRIX man pages -> complib/cpttrs (3)
 Title
 Content
 Arch
 Section All Sections 1 - General Commands 2 - System Calls 3 - Subroutines 4 - Special Files 5 - File Formats 6 - Games 7 - Macros and Conventions 8 - Maintenance Commands 9 - Kernel Interface n - New Commands

### Contents

```
CPTTRS(3F)							    CPTTRS(3F)

```

### NAME[Toc][Back]

```     CPTTRS - solve a system of	linear equations A * X = B with	a Hermitian
positive definite tridiagonal matrix A using the factorization A =
U**H*D*U or A = L*D*L**H computed by CPTTRF
```

### SYNOPSIS[Toc][Back]

```     SUBROUTINE	CPTTRS(	UPLO, N, NRHS, D, E, B,	LDB, INFO )

CHARACTER	UPLO

INTEGER	INFO, LDB, N, NRHS

REAL		D( * )

COMPLEX	B( LDB,	* ), E(	* )
```

### PURPOSE[Toc][Back]

```     CPTTRS solves a system of linear equations	A * X =	B with a Hermitian
positive definite tridiagonal matrix A using the factorization A =
U**H*D*U or A = L*D*L**H computed by CPTTRF.

```

### ARGUMENTS[Toc][Back]

```     UPLO    (input) CHARACTER*1
Specifies whether the superdiagonal or the	subdiagonal of the
tridiagonal matrix	A is stored and	the form of the	factorization:
= 'U':  E is the superdiagonal of U, and A	= U'*D*U;
= 'L':  E is the subdiagonal of L,	and A =	L*D*L'.	 (The two
forms are equivalent if A is real.)

N	     (input) INTEGER
The order of the tridiagonal 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.

D	     (input) REAL array, dimension (N)
The n diagonal elements of	the diagonal matrix D from the
factorization computed by CPTTRF.

E	     (input) COMPLEX array, dimension (N-1)
The (n-1) off-diagonal elements of	the unit bidiagonal factor U
or	L from the factorization computed by CPTTRF (see UPLO).

B	     (input/output) REAL 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).

Page 1

CPTTRS(3F)							    CPTTRS(3F)

INFO    (output) INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value
CPTTRS(3F)							    CPTTRS(3F)

```

### NAME[Toc][Back]

```     CPTTRS - solve a system of	linear equations A * X = B with	a Hermitian
positive definite tridiagonal matrix A using the factorization A =
U**H*D*U or A = L*D*L**H computed by CPTTRF
```

### SYNOPSIS[Toc][Back]

```     SUBROUTINE	CPTTRS(	UPLO, N, NRHS, D, E, B,	LDB, INFO )

CHARACTER	UPLO

INTEGER	INFO, LDB, N, NRHS

REAL		D( * )

COMPLEX	B( LDB,	* ), E(	* )
```

### PURPOSE[Toc][Back]

```     CPTTRS solves a system of linear equations	A * X =	B with a Hermitian
positive definite tridiagonal matrix A using the factorization A =
U**H*D*U or A = L*D*L**H computed by CPTTRF.

```

### ARGUMENTS[Toc][Back]

```     UPLO    (input) CHARACTER*1
Specifies whether the superdiagonal or the	subdiagonal of the
tridiagonal matrix	A is stored and	the form of the	factorization:
= 'U':  E is the superdiagonal of U, and A	= U'*D*U;
= 'L':  E is the subdiagonal of L,	and A =	L*D*L'.	 (The two
forms are equivalent if A is real.)

N	     (input) INTEGER
The order of the tridiagonal 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.

D	     (input) REAL array, dimension (N)
The n diagonal elements of	the diagonal matrix D from the
factorization computed by CPTTRF.

E	     (input) COMPLEX array, dimension (N-1)
The (n-1) off-diagonal elements of	the unit bidiagonal factor U
or	L from the factorization computed by CPTTRF (see UPLO).

B	     (input/output) REAL 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).

Page 1

CPTTRS(3F)							    CPTTRS(3F)

INFO    (output) INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value

PPPPaaaaggggeeee 2222```
[ Back ]
Similar pages