# lapmt - Man Page

lapmt: permute cols

## Synopsis

### Functions

subroutine clapmt (forwrd, m, n, x, ldx, k)
CLAPMT performs a forward or backward permutation of the columns of a matrix.
subroutine dlapmt (forwrd, m, n, x, ldx, k)
DLAPMT performs a forward or backward permutation of the columns of a matrix.
subroutine slapmt (forwrd, m, n, x, ldx, k)
SLAPMT performs a forward or backward permutation of the columns of a matrix.
subroutine zlapmt (forwrd, m, n, x, ldx, k)
ZLAPMT performs a forward or backward permutation of the columns of a matrix.

## Function Documentation

### subroutine clapmt (logical forwrd, integer m, integer n, complex, dimension( ldx, * ) x, integer ldx, integer, dimension( * ) k)

CLAPMT performs a forward or backward permutation of the columns of a matrix.

Purpose:

``` CLAPMT rearranges the columns of the M by N matrix X as specified
by the permutation K(1),K(2),...,K(N) of the integers 1,...,N.
If FORWRD = .TRUE.,  forward permutation:

X(*,K(J)) is moved X(*,J) for J = 1,2,...,N.

If FORWRD = .FALSE., backward permutation:

X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N.```
Parameters

FORWRD

```          FORWRD is LOGICAL
= .TRUE., forward permutation
= .FALSE., backward permutation```

M

```          M is INTEGER
The number of rows of the matrix X. M >= 0.```

N

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

X

```          X is COMPLEX array, dimension (LDX,N)
On entry, the M by N matrix X.
On exit, X contains the permuted matrix X.```

LDX

```          LDX is INTEGER
The leading dimension of the array X, LDX >= MAX(1,M).```

K

```          K is INTEGER array, dimension (N)
On entry, K contains the permutation vector. K is used as
internal workspace, but reset to its original value on
output.```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 103 of file clapmt.f.

### subroutine dlapmt (logical forwrd, integer m, integer n, double precision, dimension( ldx, * ) x, integer ldx, integer, dimension( * ) k)

DLAPMT performs a forward or backward permutation of the columns of a matrix.

Purpose:

``` DLAPMT rearranges the columns of the M by N matrix X as specified
by the permutation K(1),K(2),...,K(N) of the integers 1,...,N.
If FORWRD = .TRUE.,  forward permutation:

X(*,K(J)) is moved X(*,J) for J = 1,2,...,N.

If FORWRD = .FALSE., backward permutation:

X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N.```
Parameters

FORWRD

```          FORWRD is LOGICAL
= .TRUE., forward permutation
= .FALSE., backward permutation```

M

```          M is INTEGER
The number of rows of the matrix X. M >= 0.```

N

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

X

```          X is DOUBLE PRECISION array, dimension (LDX,N)
On entry, the M by N matrix X.
On exit, X contains the permuted matrix X.```

LDX

```          LDX is INTEGER
The leading dimension of the array X, LDX >= MAX(1,M).```

K

```          K is INTEGER array, dimension (N)
On entry, K contains the permutation vector. K is used as
internal workspace, but reset to its original value on
output.```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 103 of file dlapmt.f.

### subroutine slapmt (logical forwrd, integer m, integer n, real, dimension( ldx, * ) x, integer ldx, integer, dimension( * ) k)

SLAPMT performs a forward or backward permutation of the columns of a matrix.

Purpose:

``` SLAPMT rearranges the columns of the M by N matrix X as specified
by the permutation K(1),K(2),...,K(N) of the integers 1,...,N.
If FORWRD = .TRUE.,  forward permutation:

X(*,K(J)) is moved X(*,J) for J = 1,2,...,N.

If FORWRD = .FALSE., backward permutation:

X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N.```
Parameters

FORWRD

```          FORWRD is LOGICAL
= .TRUE., forward permutation
= .FALSE., backward permutation```

M

```          M is INTEGER
The number of rows of the matrix X. M >= 0.```

N

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

X

```          X is REAL array, dimension (LDX,N)
On entry, the M by N matrix X.
On exit, X contains the permuted matrix X.```

LDX

```          LDX is INTEGER
The leading dimension of the array X, LDX >= MAX(1,M).```

K

```          K is INTEGER array, dimension (N)
On entry, K contains the permutation vector. K is used as
internal workspace, but reset to its original value on
output.```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 103 of file slapmt.f.

### subroutine zlapmt (logical forwrd, integer m, integer n, complex*16, dimension( ldx, * ) x, integer ldx, integer, dimension( * ) k)

ZLAPMT performs a forward or backward permutation of the columns of a matrix.

Purpose:

``` ZLAPMT rearranges the columns of the M by N matrix X as specified
by the permutation K(1),K(2),...,K(N) of the integers 1,...,N.
If FORWRD = .TRUE.,  forward permutation:

X(*,K(J)) is moved X(*,J) for J = 1,2,...,N.

If FORWRD = .FALSE., backward permutation:

X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N.```
Parameters

FORWRD

```          FORWRD is LOGICAL
= .TRUE., forward permutation
= .FALSE., backward permutation```

M

```          M is INTEGER
The number of rows of the matrix X. M >= 0.```

N

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

X

```          X is COMPLEX*16 array, dimension (LDX,N)
On entry, the M by N matrix X.
On exit, X contains the permuted matrix X.```

LDX

```          LDX is INTEGER
The leading dimension of the array X, LDX >= MAX(1,M).```

K

```          K is INTEGER array, dimension (N)
On entry, K contains the permutation vector. K is used as
internal workspace, but reset to its original value on
output.```
Author

Univ. of Tennessee

Univ. of California Berkeley