#! /bin/sh
#
#    Last change: Mihai Dima 2001
#
if [ $# -lt 2 ]
then
  echo " "
  echo "      *****     ANNUAL MEANS     *****      "
  echo " "
  echo "           The program calculates "
  echo " annual means (file2) from monthly means (file1)"
  echo " "
  echo "    Syntax: anmean <file1> <file2>"
  echo " "
  exit 0
else
 echo " "
 echo "      *****     ANNUAL MEANS     *****      "
 echo " "
 echo "file1="$1
 echo "file2="$2
 cp $1 fort.1
fi
cat > anmean.f << EOF
      PROGRAM ANMEAN

      PARAMETER(NCHAN1=1,UNDEF=0.9E+10)
      
      REAL X(20000),XMEDAN(20000)
      INTEGER ICOUNT(20000)
      INTEGER IDAT,IVAR,ILEV,ILEN,I,J
    
      CALL PARLES (NCHAN1,IDIM1,ILEN)

      IINREG=0
      ICONTOR=0
      DO I=1,IDIM1
        XMEDAN(I)=0.0
        ICOUNT(I)=0
      ENDDO

66    READ(1,END=77) IDAT,IVAR,ILEV,IDIM1
      READ(1)(X(I),I=1,IDIM1)
      DO J=1,IDIM1
        IF (X(J).NE.UNDEF) THEN
          XMEDAN(J)=XMEDAN(J)+X(J)
          ICOUNT(J)=ICOUNT(J)+1
        ENDIF
      ENDDO
      ICONTOR=ICONTOR+1
      IF (ICONTOR.EQ.12) THEN
        DO J=1,IDIM1
          IF (ICOUNT(J).EQ.0) THEN
            XMEDAN(J)=UNDEF
          ELSE
            XMEDAN(J)=XMEDAN(J)/REAL(ICOUNT(J))
            ICOUNT(J)=0
          ENDIF
        ENDDO
        WRITE(2) IDAT,IVAR,ILEV,IDIM1
        WRITE(2) (XMEDAN(J),J=1,IDIM1)
        DO I=1,IDIM1
          XMEDAN(I)=0.0
          ICOUNT(I)=0
        ENDDO
        IINREG=IINREG+1
        ICONTOR=0
      ENDIF

      GOTO 66

77    PRINT *,' ',IINREG,' RECORDS WRITTEN!'
      PRINT*,' REGULAR END!'


      END
C**********************************************************************
      SUBROUTINE PARLES (NCHAN,IDIM,ILEN)
      IMPLICIT REAL (A-H,O-Z)
      INTEGER I1,I2,I3
      REAL F

      ILEN=0

      REWIND NCHAN
      READ(NCHAN,END=10) ITIME,INAME,ILEV,ISIZE
      GOTO 20
   10 PRINT *,'INPUT FILE ON TAPE',NCHAN,' IS EMPTY'
      STOP 'MISTAKE'
   20 REWIND NCHAN

      IDIM=0  
    1 READ (NCHAN,END=100) I1,I2,I3,I4
      IDIM=MAX0(IDIM,I4)
      READ (NCHAN,END=101) F
      ILEN=ILEN+1
      GOTO1
      
  101 PRINT *,' MORE HEADER THEN DATA '     
  100 PRINT 1000,NCHAN,IDIM,ILEN
      REWIND NCHAN
      RETURN    
 1000 FORMAT (1X,' TAPE=',I2,',  IDIM=',I5,',  ILEN=',I5)
      END
EOF
f77 anmean.f -o anmean.x
anmean.x $1 $2
cp fort.2 $2
rm fort.1 fort.2
rm anmean.x anmean.f
exit