LAPMT - 5.2 English - 68552

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

Purpose:

  LAPMT 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 – [in]

  FORWRD is LOGICAL

  = .TRUE., forward permutation

  = .FALSE., backward permutation

• M – [in]

  M is INTEGER

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

• N – [in]

  N is INTEGER

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

• X – [inout]

  X is REAL array, dimension (LDX,N)

  On entry, the M by N matrix X.

  On exit, X contains the permuted matrix X.

• LDX – [in]

  LDX is INTEGER

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

• K – [inout]

  K is INTEGER array, dimension (M)

  On entry, K contains the permutation vector. K is used as internal workspace, but reset to its original value on output.