_lag2_ - Man Page

<em>lag2</em>: general matrix, convert double <=> single

Synopsis

Functions

subroutine clag2z (m, n, sa, ldsa, a, lda, info)
CLAG2Z converts a complex single precision matrix to a complex double precision matrix.
subroutine dlag2s (m, n, a, lda, sa, ldsa, info)
DLAG2S converts a double precision matrix to a single precision matrix.
subroutine slag2d (m, n, sa, ldsa, a, lda, info)
SLAG2D converts a single precision matrix to a double precision matrix.
subroutine zlag2c (m, n, a, lda, sa, ldsa, info)
ZLAG2C converts a complex double precision matrix to a complex single precision matrix.

Function Documentation

subroutine clag2z (integer m, integer n, complex, dimension( ldsa, * ) sa, integer ldsa, complex*16, dimension( lda, * ) a, integer lda, integer info)

CLAG2Z converts a complex single precision matrix to a complex double precision matrix.

Purpose:

``` CLAG2Z converts a COMPLEX matrix, SA, to a COMPLEX*16 matrix, A.

Note that while it is possible to overflow while converting
from double to single, it is not possible to overflow when
converting from single to double.

This is an auxiliary routine so there is no argument checking.```
Parameters

M

```          M is INTEGER
The number of lines of the matrix A.  M >= 0.```

N

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

SA

```          SA is COMPLEX array, dimension (LDSA,N)
On entry, the M-by-N coefficient matrix SA.```

LDSA

```          LDSA is INTEGER
The leading dimension of the array SA.  LDSA >= max(1,M).```

A

```          A is COMPLEX*16 array, dimension (LDA,N)
On exit, the M-by-N coefficient matrix A.```

LDA

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

INFO

```          INFO is INTEGER
= 0:  successful exit```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 102 of file clag2z.f.

subroutine dlag2s (integer m, integer n, double precision, dimension( lda, * ) a, integer lda, real, dimension( ldsa, * ) sa, integer ldsa, integer info)

DLAG2S converts a double precision matrix to a single precision matrix.

Purpose:

``` DLAG2S converts a DOUBLE PRECISION matrix, A, to a SINGLE
PRECISION matrix, SA.

RMAX is the overflow for the SINGLE PRECISION arithmetic
DLAG2S checks that all the entries of A are between -RMAX and
RMAX. If not the conversion is aborted and a flag is raised.

This is an auxiliary routine so there is no argument checking.```
Parameters

M

```          M is INTEGER
The number of lines of the matrix A.  M >= 0.```

N

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

A

```          A is DOUBLE PRECISION array, dimension (LDA,N)
On entry, the M-by-N coefficient matrix A.```

LDA

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

SA

```          SA is REAL array, dimension (LDSA,N)
On exit, if INFO=0, the M-by-N coefficient matrix SA; if
INFO>0, the content of SA is unspecified.```

LDSA

```          LDSA is INTEGER
The leading dimension of the array SA.  LDSA >= max(1,M).```

INFO

```          INFO is INTEGER
= 0:  successful exit.
= 1:  an entry of the matrix A is greater than the SINGLE
PRECISION overflow threshold, in this case, the content
of SA in exit is unspecified.```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 107 of file dlag2s.f.

subroutine slag2d (integer m, integer n, real, dimension( ldsa, * ) sa, integer ldsa, double precision, dimension( lda, * ) a, integer lda, integer info)

SLAG2D converts a single precision matrix to a double precision matrix.

Purpose:

``` SLAG2D converts a SINGLE PRECISION matrix, SA, to a DOUBLE
PRECISION matrix, A.

Note that while it is possible to overflow while converting
from double to single, it is not possible to overflow when
converting from single to double.

This is an auxiliary routine so there is no argument checking.```
Parameters

M

```          M is INTEGER
The number of lines of the matrix A.  M >= 0.```

N

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

SA

```          SA is REAL array, dimension (LDSA,N)
On entry, the M-by-N coefficient matrix SA.```

LDSA

```          LDSA is INTEGER
The leading dimension of the array SA.  LDSA >= max(1,M).```

A

```          A is DOUBLE PRECISION array, dimension (LDA,N)
On exit, the M-by-N coefficient matrix A.```

LDA

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

INFO

```          INFO is INTEGER
= 0:  successful exit```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 103 of file slag2d.f.

subroutine zlag2c (integer m, integer n, complex*16, dimension( lda, * ) a, integer lda, complex, dimension( ldsa, * ) sa, integer ldsa, integer info)

ZLAG2C converts a complex double precision matrix to a complex single precision matrix.

Purpose:

``` ZLAG2C converts a COMPLEX*16 matrix, SA, to a COMPLEX matrix, A.

RMAX is the overflow for the SINGLE PRECISION arithmetic
ZLAG2C checks that all the entries of A are between -RMAX and
RMAX. If not the conversion is aborted and a flag is raised.

This is an auxiliary routine so there is no argument checking.```
Parameters

M

```          M is INTEGER
The number of lines of the matrix A.  M >= 0.```

N

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

A

```          A is COMPLEX*16 array, dimension (LDA,N)
On entry, the M-by-N coefficient matrix A.```

LDA

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

SA

```          SA is COMPLEX array, dimension (LDSA,N)
On exit, if INFO=0, the M-by-N coefficient matrix SA; if
INFO>0, the content of SA is unspecified.```

LDSA

```          LDSA is INTEGER
The leading dimension of the array SA.  LDSA >= max(1,M).```

INFO

```          INFO is INTEGER
= 0:  successful exit.
= 1:  an entry of the matrix A is greater than the SINGLE
PRECISION overflow threshold, in this case, the content
of SA in exit is unspecified.```
Author

Univ. of Tennessee

Univ. of California Berkeley