# dlapmt.f man page

dlapmt.f —

## Synopsis

### Functions/Subroutines

subroutinedlapmt(FORWRD, M, N, X, LDX, K)DLAPMTperforms a forward or backward permutation of the columns of a matrix.

## Function/Subroutine Documentation

### subroutine dlapmt (logicalFORWRD, integerM, integerN, double precision, dimension( ldx, * )X, integerLDX, 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

Univ. of Colorado Denver

NAG Ltd.

**Date:**

September 2012

Definition at line 105 of file dlapmt.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

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