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+ SUBROUTINE DLAPMT( FORWRD, M, N, X, LDX, K )
+*
+* -- LAPACK auxiliary routine (version 3.1) --
+* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
+* November 2006
+*
+* .. Scalar Arguments ..
+ LOGICAL FORWRD
+ INTEGER LDX, M, N
+* ..
+* .. Array Arguments ..
+ INTEGER K( * )
+ DOUBLE PRECISION X( LDX, * )
+* ..
+*
+* 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.
+*
+* Arguments
+* =========
+*
+* FORWRD (input) LOGICAL
+* = .TRUE., forward permutation
+* = .FALSE., backward permutation
+*
+* M (input) INTEGER
+* The number of rows of the matrix X. M >= 0.
+*
+* N (input) INTEGER
+* The number of columns of the matrix X. N >= 0.
+*
+* X (input/output) DOUBLE PRECISION array, dimension (LDX,N)
+* On entry, the M by N matrix X.
+* On exit, X contains the permuted matrix X.
+*
+* LDX (input) INTEGER
+* The leading dimension of the array X, LDX >= MAX(1,M).
+*
+* K (input/output) 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.
+*
+* =====================================================================
+*
+* .. Local Scalars ..
+ INTEGER I, II, IN, J
+ DOUBLE PRECISION TEMP
+* ..
+* .. Executable Statements ..
+*
+ IF( N.LE.1 )
+ $ RETURN
+*
+ DO 10 I = 1, N
+ K( I ) = -K( I )
+ 10 CONTINUE
+*
+ IF( FORWRD ) THEN
+*
+* Forward permutation
+*
+ DO 50 I = 1, N
+*
+ IF( K( I ).GT.0 )
+ $ GO TO 40
+*
+ J = I
+ K( J ) = -K( J )
+ IN = K( J )
+*
+ 20 CONTINUE
+ IF( K( IN ).GT.0 )
+ $ GO TO 40
+*
+ DO 30 II = 1, M
+ TEMP = X( II, J )
+ X( II, J ) = X( II, IN )
+ X( II, IN ) = TEMP
+ 30 CONTINUE
+*
+ K( IN ) = -K( IN )
+ J = IN
+ IN = K( IN )
+ GO TO 20
+*
+ 40 CONTINUE
+*
+ 50 CONTINUE
+*
+ ELSE
+*
+* Backward permutation
+*
+ DO 90 I = 1, N
+*
+ IF( K( I ).GT.0 )
+ $ GO TO 80
+*
+ K( I ) = -K( I )
+ J = K( I )
+ 60 CONTINUE
+ IF( J.EQ.I )
+ $ GO TO 80
+*
+ DO 70 II = 1, M
+ TEMP = X( II, I )
+ X( II, I ) = X( II, J )
+ X( II, J ) = TEMP
+ 70 CONTINUE
+*
+ K( J ) = -K( J )
+ J = K( J )
+ GO TO 60
+*
+ 80 CONTINUE
+*
+ 90 CONTINUE
+*
+ END IF
+*
+ RETURN
+*
+* End of DLAPMT
+*
+ END