      SUBROUTINE COPY(X,N,Y)
C
C     PURPOSE--THIS SUBROUTINE COPIES THE CONTENTS
C              OF THE SINGLE PRECISION VECTOR X INTO THE
C              SINGLE PRECISION VECTOR Y.
C     INPUT  ARGUMENTS--X      = THE SINGLE PRECISION VECTOR OF
C                                OBSERVATIONS TO BE COPIED. 
C                     --N      = THE INTEGER NUMBER OF OBSERVATIONS
C                                IN THE VECTOR X. 
C     OUTPUT ARGUMENTS--Y      = THE SINGLE PRECISION VECTOR
C                                INTO WHICH THE COPIED DATA VALUES
C                                FROM X WILL BE SEQUENTIALLY PLACED.
C     OUTPUT--THE SINGLE PRECISION VECTOR Y.
C             WHICH WILL HAVE ITS
C             FIRST N ELEMENTS IDENTICAL
C             TO THE SINGLE PRECISION VECTOR X.
C     PRINTING--NONE UNLESS AN INPUT ARGUMENT ERROR CONDITION EXISTS. 
C     RESTRICTIONS--THERE IS NO RESTRICTION ON THE MAXIMUM VALUE
C                   OF N FOR THIS SUBROUTINE.
C     OTHER DATAPAC   SUBROUTINES NEEDED--NONE.
C     FORTRAN LIBRARY SUBROUTINES NEEDED--NONE.
C     MODE OF INTERNAL OPERATIONS--SINGLE PRECISION.
C     LANGUAGE--ANSI FORTRAN. 
C     COMMENT--THE FIRST ELEMENT OF X IS COPIED INTO THE FIRST
C              ELEMENT OF Y; THE SECOND ELEMENT OF X IS COPIED INTO
C              THE SECOND ELEMENT OF Y, ETC.
C     COMMENT--THE INPUT VECTOR X REMAINS UNALTERED.
C     REFERENCES--NONE.
C     WRITTEN BY--JAMES J. FILLIBEN
C                 STATISTICAL ENGINEERING LABORATORY (205.03)
C                 NATIONAL BUREAU OF STANDARDS
C                 WASHINGTON, D. C. 20234
C                 PHONE--301-921-2315
C     ORIGINAL VERSION--NOVEMBER  1972. 
C     UPDATED         --NOVEMBER  1975. 
C
C---------------------------------------------------------------------
C
      DIMENSION X(1),Y(1)
C
      IPR=6
C
C     CHECK THE INPUT ARGUMENTS FOR ERRORS
C
      IF(N.LT.1)GOTO50
      IF(N.EQ.1)GOTO55
      HOLD=X(1)
      DO60I=2,N
      IF(X(I).NE.HOLD)GOTO90
   60 CONTINUE
      WRITE(IPR, 9)HOLD
      GOTO90
   50 WRITE(IPR,15) 
      WRITE(IPR,47)N
      RETURN
   55 WRITE(IPR,18) 
   90 CONTINUE
    9 FORMAT(1H ,108H***** NON-FATAL DIAGNOSTIC--THE FIRST  INPUT ARGUME
     1NT (A VECTOR) TO THE COPY   SUBROUTINE HAS ALL ELEMENTS = ,E15.8,6
     1H *****)
   15 FORMAT(1H , 91H***** FATAL ERROR--THE SECOND INPUT ARGUMENT TO THE
     1 COPY   SUBROUTINE IS NON-POSITIVE *****)
   18 FORMAT(1H ,100H***** NON-FATAL DIAGNOSTIC--THE SECOND INPUT ARGUME
     1NT TO THE COPY   SUBROUTINE HAS THE VALUE 1 *****)
   47 FORMAT(1H , 35H***** THE VALUE OF THE ARGUMENT IS ,I8   ,6H *****)
C
C-----START POINT-----------------------------------------------------
C
      DO100I=1,N
      Y(I)=X(I)
  100 CONTINUE
C
      RETURN
      END 
