C CXB50051.FTN
C
C                         Grant of Unlimited Rights
C
C Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
C F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained 
C unlimited rights in the software and documentation contained herein.
C Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making 
C this public release, the Government intends to confer upon all 
C recipients unlimited rights  equal to those held by the Government.  
C These rights include rights to use, duplicate, release or disclose the 
C released technical data and computer software in whole or in part, in 
C any manner and for any purpose whatsoever, and to have or permit others 
C to do so.
C
C                                DISCLAIMER
C
C ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
C DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED 
C WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
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C PARTICULAR PURPOSE OF SAID MATERIAL.
C
C----------------------------------------------------------------------
C TEST OBJECTIVE
C      See CXB50052.AM
C
C TEST DESCRIPTION
C      The following Fortran subroutine, CXB50051, has two arguments.
C      The modified matrix is returned to the calling program.
C
C      Inputs:
C        There are two arguments to this Fortran subroutine:
C          1) N      - an integer value that indicates the array size.
C          2) MATRIX - a two-dimensional integer array.
C
C      Processing:
C        The matrix argument is modified in the following manner:
C          The array diagonal elements are filled with 1's, the elements 
C          below/left of the diagonal are filled with 2's, and the elements
C          above/right of the diagonal are filled with 3's.
C
C      Outputs:
C        The modified array argument is returned.
C
C SPECIAL REQUIREMENTS:
C      See CXB50052.AM
C     
C TEST FILES:
C      The following files comprise this test:
C
C         CXB50050.FTN
C      => CXB50051.FTN
C         CXB50052.AM
C
C APPLICABILITY CRITERIA: 
C      See CXB50052.AM
C
C
C CHANGE HISTORY:
C       28 Mar 1996     SAIC     Initial release for ACVC 2.1.
C       14 Feb 1997     PWB.CTA  Corrected Fortran syntax errors
C 
C----------------------------------------------------------------------
C
      SUBROUTINE MODIFY (N, MATRIX)
C
      INTEGER   N, I, J
      INTEGER   MATRIX(1:N, 1:N)
C
C     Modify the contents of the array.
C
      DO 100 I = 1, N
        DO 100 J = 1, N
          IF (I .EQ. J) THEN
            MATRIX(I,J) = 1
          ELSE IF (I .GT. J) THEN
            MATRIX(I,J) = 2
          ELSE
            MATRIX(I,J) = 3
          ENDIF
 100  CONTINUE
C
      RETURN
      END