C++*********************************************************************
C
C  BLANK.F
C
C **********************************************************************
C=*                                                                    *
C=* This file is part of:   SPIDER - Modular Image Processing System.  *
C=* SPIDER System Authors:  Joachim Frank & ArDean Leith               *
C=* Copyright 1985-2010  Health Research Inc.,                         *
C=* Riverview Center, 150 Broadway, Suite 560, Menands, NY 12204.      *
C=* Email: spider@wadsworth.org                                        *
C=*                                                                    *
C=* SPIDER is free software; you can redistribute it and/or            *
C=* modify it under the terms of the GNU General Public License as     *
C=* published by the Free Software Foundation; either version 2 of the *
C=* License, or (at your option) any later version.                    *
C=*                                                                    *
C=* SPIDER is distributed in the hope that it will be useful,          *
C=* but WITHOUT ANY WARRANTY; without even the implied warranty of     *
C=* merchantability or fitness for a particular purpose.  See the GNU  *
C=* General Public License for more details.                           *
C=* You should have received a copy of the GNU General Public License  *
C=* along with this program. If not, see <http://www.gnu.org/licenses> *
C=*                                                                    *
C **********************************************************************
C
C      BLANK(LUN,NSAM,NROW,B)
C
C      THIS SUBROUTINE CREATES A CONSTANT PICTURE WITH A GIVEN
C      BACKGROUND VALUE.
C
C      PARAMETERS:
C        LUN          LOGICAL UNIT NUMBER OF OUTPUT PICTURE
C        NSAM,NROW    DIMENSIONS OF OUTPUT PICTURE
C        B            BACKGROUND CONSTANT TO BE USED
C
C--********************************************************************

        SUBROUTINE BLANK(LUN,NSAM,NROW,NSLICE,B)

        DIMENSION BUF(NSAM)

	BUF = B
        DO  I = 1,NROW*NSLICE
	   CALL WRTLIN(LUN,BUF,NSAM,I)
        ENDDO
        END