| 1 | subroutine gf_unpack2(cgrib,lcgrib,iofst,lencsec2,csec2,ierr) |
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| 2 | !$$$ SUBPROGRAM DOCUMENTATION BLOCK |
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| 3 | ! . . . . |
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| 4 | ! SUBPROGRAM: gf_unpack2 |
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| 5 | ! PRGMMR: Gilbert ORG: W/NP11 DATE: 2002-04-09 |
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| 6 | ! |
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| 7 | ! ABSTRACT: This subroutine unpacks Section 2 (Local Use Section) |
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| 8 | ! as defined in GRIB Edition 2. |
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| 9 | ! |
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| 10 | ! PROGRAM HISTORY LOG: |
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| 11 | ! 2002-04-09 Gilbert |
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| 12 | ! |
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| 13 | ! USAGE: CALL gf_unpack2(cgrib,lcgrib,iofst,lencsec2,csec2,ierr) |
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| 14 | ! INPUT ARGUMENT LIST: |
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| 15 | ! cgrib - Character array containing Section 2 of the GRIB2 message |
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| 16 | ! lcgrib - Length (in bytes) of GRIB message array cgrib. |
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| 17 | ! iofst - Bit offset of the beginning of Section 2. |
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| 18 | ! |
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| 19 | ! OUTPUT ARGUMENT LIST: |
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| 20 | ! iofst - Bit offset at the end of Section 2, returned. |
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| 21 | ! lencsec2 - Length (in octets) of Local Use data |
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| 22 | ! csec2() - Pointer to a character*1 array containing local use data |
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| 23 | ! ierr - Error return code. |
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| 24 | ! 0 = no error |
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| 25 | ! 2 = Array passed is not section 2 |
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| 26 | ! 6 = memory allocation error |
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| 27 | ! |
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| 28 | ! REMARKS: None |
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| 29 | ! |
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| 30 | ! ATTRIBUTES: |
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| 31 | ! LANGUAGE: Fortran 90 |
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| 32 | ! MACHINE: IBM SP |
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| 33 | ! |
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| 34 | !$$$ |
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| 35 | |
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| 36 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 37 | integer,intent(in) :: lcgrib |
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| 38 | integer,intent(inout) :: iofst |
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| 39 | integer,intent(out) :: lencsec2 |
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| 40 | integer,intent(out) :: ierr |
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| 41 | character(len=1),pointer,dimension(:) :: csec2 |
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| 42 | |
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| 43 | ierr=0 |
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| 44 | lencsec2=0 |
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| 45 | nullify(csec2) |
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| 46 | |
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| 47 | call g2lib_gbyte(cgrib,lensec,iofst,32) ! Get Length of Section |
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| 48 | iofst=iofst+32 |
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| 49 | lencsec2=lensec-5 |
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| 50 | call g2lib_gbyte(cgrib,isecnum,iofst,8) ! Get Section Number |
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| 51 | iofst=iofst+8 |
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| 52 | ipos=(iofst/8)+1 |
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| 53 | |
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| 54 | if ( isecnum.ne.2 ) then |
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| 55 | ierr=6 |
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| 56 | print *,'gf_unpack2: Not Section 2 data. ' |
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| 57 | return |
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| 58 | endif |
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| 59 | |
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| 60 | allocate(csec2(lencsec2),stat=istat) |
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| 61 | if (istat.ne.0) then |
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| 62 | ierr=6 |
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| 63 | nullify(csec2) |
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| 64 | return |
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| 65 | endif |
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| 66 | |
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| 67 | csec2(1:lencsec2)=cgrib(ipos:ipos+lencsec2-1) |
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| 68 | iofst=iofst+(lencsec2*8) |
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| 69 | |
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| 70 | return ! End of Section 2 processing |
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| 71 | end |
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| 72 | |
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