```      SUBROUTINE SLAMRG( N1, N2, A, STRD1, STRD2, INDEX )
*
*  -- LAPACK routine (version 3.1) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2006
*
*     .. Scalar Arguments ..
INTEGER            N1, N2, STRD1, STRD2
*     ..
*     .. Array Arguments ..
INTEGER            INDEX( * )
REAL               A( * )
*     ..
*
*  Purpose
*  =======
*
*  SLAMRG will create a permutation list which will merge the elements
*  of A (which is composed of two independently sorted sets) into a
*  single set which is sorted in ascending order.
*
*  Arguments
*  =========
*
*  N1     (input) INTEGER
*  N2     (input) INTEGER
*         These arguements contain the respective lengths of the two
*         sorted lists to be merged.
*
*  A      (input) REAL array, dimension (N1+N2)
*         The first N1 elements of A contain a list of numbers which
*         are sorted in either ascending or descending order.  Likewise
*         for the final N2 elements.
*
*  STRD1  (input) INTEGER
*  STRD2  (input) INTEGER
*         These are the strides to be taken through the array A.
*         Allowable strides are 1 and -1.  They indicate whether a
*         subset of A is sorted in ascending (STRDx = 1) or descending
*         (STRDx = -1) order.
*
*  INDEX  (output) INTEGER array, dimension (N1+N2)
*         On exit this array will contain a permutation such that
*         if B( I ) = A( INDEX( I ) ) for I=1,N1+N2, then B will be
*         sorted in ascending order.
*
*  =====================================================================
*
*     .. Local Scalars ..
INTEGER            I, IND1, IND2, N1SV, N2SV
*     ..
*     .. Executable Statements ..
*
N1SV = N1
N2SV = N2
IF( STRD1.GT.0 ) THEN
IND1 = 1
ELSE
IND1 = N1
END IF
IF( STRD2.GT.0 ) THEN
IND2 = 1 + N1
ELSE
IND2 = N1 + N2
END IF
I = 1
*     while ( (N1SV > 0) & (N2SV > 0) )
10 CONTINUE
IF( N1SV.GT.0 .AND. N2SV.GT.0 ) THEN
IF( A( IND1 ).LE.A( IND2 ) ) THEN
INDEX( I ) = IND1
I = I + 1
IND1 = IND1 + STRD1
N1SV = N1SV - 1
ELSE
INDEX( I ) = IND2
I = I + 1
IND2 = IND2 + STRD2
N2SV = N2SV - 1
END IF
GO TO 10
END IF
*     end while
IF( N1SV.EQ.0 ) THEN
DO 20 N1SV = 1, N2SV
INDEX( I ) = IND2
I = I + 1
IND2 = IND2 + STRD2
20    CONTINUE
ELSE
*     N2SV .EQ. 0
DO 30 N2SV = 1, N1SV
INDEX( I ) = IND1
I = I + 1
IND1 = IND1 + STRD1
30    CONTINUE
END IF
*
RETURN
*
*     End of SLAMRG
*
END

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