| 1 | subroutine gf_getfld(cgrib,lcgrib,ifldnum,unpack,expand,gfld,ierr) |
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| 2 | !$$$ SUBPROGRAM DOCUMENTATION BLOCK |
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| 3 | ! . . . . |
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| 4 | ! SUBPROGRAM: gf_getfld |
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| 5 | ! PRGMMR: Gilbert ORG: W/NP11 DATE: 2000-05-26 |
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| 6 | ! |
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| 7 | ! ABSTRACT: This subroutine returns the Grid Definition, Product Definition, |
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| 8 | ! Bit-map ( if applicable ), and the unpacked data for a given data |
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| 9 | ! field. All of the information returned is stored in a derived |
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| 10 | ! type variable, gfld. Gfld is of type gribfield, which is defined |
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| 11 | ! in module grib_mod, so users of this routine will need to include |
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| 12 | ! the line "USE GRIB_MOD" in their calling routine. Each component of the |
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| 13 | ! gribfield type is described in the OUTPUT ARGUMENT LIST section below. |
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| 14 | ! |
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| 15 | ! Since there can be multiple data fields packed into a GRIB2 |
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| 16 | ! message, the calling routine indicates which field is being requested |
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| 17 | ! with the ifldnum argument. |
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| 18 | ! |
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| 19 | ! PROGRAM HISTORY LOG: |
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| 20 | ! 2000-05-26 Gilbert |
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| 21 | ! 2002-01-24 Gilbert - Changed to pass back derived type gribfield |
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| 22 | ! variable through argument list, instead of |
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| 23 | ! having many different arguments. |
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| 24 | ! 2004-05-20 Gilbert - Added check to see if previous a bit-map is specified, |
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| 25 | ! but none was found. |
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| 26 | ! |
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| 27 | ! USAGE: CALL gf_getfld(cgrib,lcgrib,ifldnum,unpack,expand,gfld,ierr) |
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| 28 | ! INPUT ARGUMENT LIST: |
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| 29 | ! cgrib - Character array that contains the GRIB2 message |
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| 30 | ! lcgrib - Length (in bytes) of GRIB message array cgrib. |
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| 31 | ! ifldnum - Specifies which field in the GRIB2 message to return. |
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| 32 | ! unpack - Logical value indicating whether to unpack bitmap/data |
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| 33 | ! .true. = unpack bitmap and data values |
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| 34 | ! .false. = do not unpack bitmap and data values |
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| 35 | ! expand - Boolean value indicating whether the data points should be |
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| 36 | ! expanded to the correspond grid, if a bit-map is present. |
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| 37 | ! 1 = if possible, expand data field to grid, inserting zero |
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| 38 | ! values at gridpoints that are bitmapped out. |
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| 39 | ! (SEE REMARKS2) |
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| 40 | ! 0 = do not expand data field, leaving it an array of |
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| 41 | ! consecutive data points for each "1" in the bitmap. |
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| 42 | ! This argument is ignored if unpack == 0 OR if the |
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| 43 | ! returned field does not contain a bit-map. |
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| 44 | ! |
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| 45 | ! OUTPUT ARGUMENT LIST: |
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| 46 | ! gfld - derived type gribfield ( defined in module grib_mod ) |
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| 47 | ! ( NOTE: See Remarks Section ) |
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| 48 | ! gfld%version = GRIB edition number ( currently 2 ) |
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| 49 | ! gfld%discipline = Message Discipline ( see Code Table 0.0 ) |
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| 50 | ! gfld%idsect() = Contains the entries in the Identification |
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| 51 | ! Section ( Section 1 ) |
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| 52 | ! This element is actually a pointer to an array |
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| 53 | ! that holds the data. |
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| 54 | ! gfld%idsect(1) = Identification of originating Centre |
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| 55 | ! ( see Common Code Table C-1 ) |
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| 56 | ! 7 - US National Weather Service |
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| 57 | ! gfld%idsect(2) = Identification of originating Sub-centre |
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| 58 | ! gfld%idsect(3) = GRIB Master Tables Version Number |
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| 59 | ! ( see Code Table 1.0 ) |
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| 60 | ! 0 - Experimental |
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| 61 | ! 1 - Initial operational version number |
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| 62 | ! gfld%idsect(4) = GRIB Local Tables Version Number |
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| 63 | ! ( see Code Table 1.1 ) |
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| 64 | ! 0 - Local tables not used |
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| 65 | ! 1-254 - Number of local tables version used |
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| 66 | ! gfld%idsect(5) = Significance of Reference Time (Code Table 1.2) |
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| 67 | ! 0 - Analysis |
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| 68 | ! 1 - Start of forecast |
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| 69 | ! 2 - Verifying time of forecast |
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| 70 | ! 3 - Observation time |
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| 71 | ! gfld%idsect(6) = Year ( 4 digits ) |
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| 72 | ! gfld%idsect(7) = Month |
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| 73 | ! gfld%idsect(8) = Day |
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| 74 | ! gfld%idsect(9) = Hour |
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| 75 | ! gfld%idsect(10) = Minute |
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| 76 | ! gfld%idsect(11) = Second |
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| 77 | ! gfld%idsect(12) = Production status of processed data |
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| 78 | ! ( see Code Table 1.3 ) |
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| 79 | ! 0 - Operational products |
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| 80 | ! 1 - Operational test products |
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| 81 | ! 2 - Research products |
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| 82 | ! 3 - Re-analysis products |
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| 83 | ! gfld%idsect(13) = Type of processed data ( see Code Table 1.4 ) |
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| 84 | ! 0 - Analysis products |
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| 85 | ! 1 - Forecast products |
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| 86 | ! 2 - Analysis and forecast products |
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| 87 | ! 3 - Control forecast products |
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| 88 | ! 4 - Perturbed forecast products |
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| 89 | ! 5 - Control and perturbed forecast products |
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| 90 | ! 6 - Processed satellite observations |
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| 91 | ! 7 - Processed radar observations |
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| 92 | ! gfld%idsectlen = Number of elements in gfld%idsect(). |
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| 93 | ! gfld%local() = Pointer to character array containing contents |
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| 94 | ! of Local Section 2, if included |
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| 95 | ! gfld%locallen = length of array gfld%local() |
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| 96 | ! gfld%ifldnum = field number within GRIB message |
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| 97 | ! gfld%griddef = Source of grid definition (see Code Table 3.0) |
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| 98 | ! 0 - Specified in Code table 3.1 |
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| 99 | ! 1 - Predetermined grid Defined by originating centre |
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| 100 | ! gfld%ngrdpts = Number of grid points in the defined grid. |
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| 101 | ! gfld%numoct_opt = Number of octets needed for each |
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| 102 | ! additional grid points definition. |
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| 103 | ! Used to define number of |
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| 104 | ! points in each row ( or column ) for |
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| 105 | ! non-regular grids. |
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| 106 | ! = 0, if using regular grid. |
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| 107 | ! gfld%interp_opt = Interpretation of list for optional points |
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| 108 | ! definition. (Code Table 3.11) |
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| 109 | ! gfld%igdtnum = Grid Definition Template Number (Code Table 3.1) |
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| 110 | ! gfld%igdtmpl() = Contains the data values for the specified Grid |
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| 111 | ! Definition Template ( NN=gfld%igdtnum ). Each |
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| 112 | ! element of this integer array contains an entry (in |
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| 113 | ! the order specified) of Grid Defintion Template 3.NN |
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| 114 | ! This element is actually a pointer to an array |
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| 115 | ! that holds the data. |
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| 116 | ! gfld%igdtlen = Number of elements in gfld%igdtmpl(). i.e. number of |
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| 117 | ! entries in Grid Defintion Template 3.NN |
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| 118 | ! ( NN=gfld%igdtnum ). |
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| 119 | ! gfld%list_opt() = (Used if gfld%numoct_opt .ne. 0) This array |
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| 120 | ! contains the number of grid points contained in |
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| 121 | ! each row ( or column ). (part of Section 3) |
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| 122 | ! This element is actually a pointer to an array |
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| 123 | ! that holds the data. This pointer is nullified |
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| 124 | ! if gfld%numoct_opt=0. |
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| 125 | ! gfld%num_opt = (Used if gfld%numoct_opt .ne. 0) The number of entries |
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| 126 | ! in array ideflist. i.e. number of rows ( or columns ) |
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| 127 | ! for which optional grid points are defined. This value |
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| 128 | ! is set to zero, if gfld%numoct_opt=0. |
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| 129 | ! gfdl%ipdtnum = Product Definition Template Number (see Code Table 4.0) |
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| 130 | ! gfld%ipdtmpl() = Contains the data values for the specified Product |
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| 131 | ! Definition Template ( N=gfdl%ipdtnum ). Each element |
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| 132 | ! of this integer array contains an entry (in the |
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| 133 | ! order specified) of Product Defintion Template 4.N. |
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| 134 | ! This element is actually a pointer to an array |
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| 135 | ! that holds the data. |
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| 136 | ! gfld%ipdtlen = Number of elements in gfld%ipdtmpl(). i.e. number of |
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| 137 | ! entries in Product Defintion Template 4.N |
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| 138 | ! ( N=gfdl%ipdtnum ). |
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| 139 | ! gfld%coord_list() = Real array containing floating point values |
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| 140 | ! intended to document the vertical discretisation |
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| 141 | ! associated to model data on hybrid coordinate |
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| 142 | ! vertical levels. (part of Section 4) |
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| 143 | ! This element is actually a pointer to an array |
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| 144 | ! that holds the data. |
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| 145 | ! gfld%num_coord = number of values in array gfld%coord_list(). |
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| 146 | ! gfld%ndpts = Number of data points unpacked and returned. |
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| 147 | ! gfld%idrtnum = Data Representation Template Number |
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| 148 | ! ( see Code Table 5.0) |
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| 149 | ! gfld%idrtmpl() = Contains the data values for the specified Data |
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| 150 | ! Representation Template ( N=gfld%idrtnum ). Each |
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| 151 | ! element of this integer array contains an entry |
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| 152 | ! (in the order specified) of Product Defintion |
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| 153 | ! Template 5.N. |
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| 154 | ! This element is actually a pointer to an array |
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| 155 | ! that holds the data. |
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| 156 | ! gfld%idrtlen = Number of elements in gfld%idrtmpl(). i.e. number |
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| 157 | ! of entries in Data Representation Template 5.N |
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| 158 | ! ( N=gfld%idrtnum ). |
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| 159 | ! gfld%unpacked = logical value indicating whether the bitmap and |
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| 160 | ! data values were unpacked. If false, |
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| 161 | ! gfld%bmap and gfld%fld pointers are nullified. |
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| 162 | ! gfld%expanded = Logical value indicating whether the data field |
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| 163 | ! was expanded to the grid in the case where a |
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| 164 | ! bit-map is present. If true, the data points in |
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| 165 | ! gfld%fld match the grid points and zeros were |
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| 166 | ! inserted at grid points where data was bit-mapped |
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| 167 | ! out. If false, the data values in gfld%fld were |
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| 168 | ! not expanded to the grid and are just a consecutive |
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| 169 | ! array of data points corresponding to each value of |
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| 170 | ! "1" in gfld%bmap. |
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| 171 | ! gfld%ibmap = Bitmap indicator ( see Code Table 6.0 ) |
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| 172 | ! 0 = bitmap applies and is included in Section 6. |
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| 173 | ! 1-253 = Predefined bitmap applies |
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| 174 | ! 254 = Previously defined bitmap applies to this field |
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| 175 | ! 255 = Bit map does not apply to this product. |
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| 176 | ! gfld%bmap() = Logical*1 array containing decoded bitmap, |
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| 177 | ! if ibmap=0 or ibap=254. Otherwise nullified. |
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| 178 | ! This element is actually a pointer to an array |
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| 179 | ! that holds the data. |
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| 180 | ! gfld%fld() = Array of gfld%ndpts unpacked data points. |
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| 181 | ! This element is actually a pointer to an array |
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| 182 | ! that holds the data. |
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| 183 | ! ierr - Error return code. |
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| 184 | ! 0 = no error |
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| 185 | ! 1 = Beginning characters "GRIB" not found. |
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| 186 | ! 2 = GRIB message is not Edition 2. |
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| 187 | ! 3 = The data field request number was not positive. |
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| 188 | ! 4 = End string "7777" found, but not where expected. |
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| 189 | ! 6 = GRIB message did not contain the requested number of |
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| 190 | ! data fields. |
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| 191 | ! 7 = End string "7777" not found at end of message. |
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| 192 | ! 8 = Unrecognized Section encountered. |
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| 193 | ! 9 = Data Representation Template 5.NN not yet implemented. |
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| 194 | ! 15 = Error unpacking Section 1. |
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| 195 | ! 16 = Error unpacking Section 2. |
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| 196 | ! 10 = Error unpacking Section 3. |
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| 197 | ! 11 = Error unpacking Section 4. |
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| 198 | ! 12 = Error unpacking Section 5. |
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| 199 | ! 13 = Error unpacking Section 6. |
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| 200 | ! 14 = Error unpacking Section 7. |
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| 201 | ! 17 = Previous bitmap specified, but none exists. |
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| 202 | ! |
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| 203 | ! REMARKS: Note that derived type gribfield contains pointers to many |
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| 204 | ! arrays of data. The memory for these arrays is allocated |
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| 205 | ! when the values in the arrays are set, to help minimize |
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| 206 | ! problems with array overloading. Because of this users |
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| 207 | ! are encouraged to free up this memory, when it is no longer |
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| 208 | ! needed, by an explicit call to subroutine gf_free. |
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| 209 | ! ( i.e. CALL GF_FREE(GFLD) ) |
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| 210 | ! |
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| 211 | ! Subroutine gb_info can be used to first determine |
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| 212 | ! how many data fields exist in a given GRIB message. |
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| 213 | ! |
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| 214 | ! REMARKS2: It may not always be possible to expand a bit-mapped data field. |
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| 215 | ! If a pre-defined bit-map is used and not included in the GRIB2 |
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| 216 | ! message itself, this routine would not have the necessary |
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| 217 | ! information to expand the data. In this case, gfld%expanded would |
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| 218 | ! would be set to 0 (false), regardless of the value of input |
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| 219 | ! argument expand. |
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| 220 | ! |
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| 221 | ! ATTRIBUTES: |
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| 222 | ! LANGUAGE: Fortran 90 |
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| 223 | ! MACHINE: IBM SP |
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| 224 | ! |
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| 225 | !$$$ |
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| 226 | use grib_mod |
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| 227 | |
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| 228 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 229 | integer,intent(in) :: lcgrib,ifldnum |
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| 230 | logical,intent(in) :: unpack,expand |
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| 231 | type(gribfield),intent(out) :: gfld |
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| 232 | integer,intent(out) :: ierr |
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| 233 | ! integer,intent(out) :: igds(*),igdstmpl(*),ideflist(*) |
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| 234 | ! integer,intent(out) :: ipdsnum,ipdstmpl(*) |
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| 235 | ! integer,intent(out) :: idrsnum,idrstmpl(*) |
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| 236 | ! integer,intent(out) :: ndpts,ibmap,idefnum,numcoord |
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| 237 | ! logical*1,intent(out) :: bmap(*) |
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| 238 | ! real,intent(out) :: fld(*),coordlist(*) |
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| 239 | |
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| 240 | character(len=4),parameter :: grib='GRIB',c7777='7777' |
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| 241 | character(len=4) :: ctemp |
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| 242 | real,pointer,dimension(:) :: newfld |
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| 243 | integer:: listsec0(2),igds(5) |
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| 244 | integer iofst,ibeg,istart |
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| 245 | integer(4) :: ieee |
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| 246 | logical*1,pointer,dimension(:) :: bmpsave |
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| 247 | logical have3,have4,have5,have6,have7 |
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| 248 | |
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| 249 | interface |
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| 250 | subroutine gf_unpack1(cgrib,lcgrib,iofst,ids,idslen,ierr) |
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| 251 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 252 | integer,intent(in) :: lcgrib |
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| 253 | integer,intent(inout) :: iofst |
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| 254 | integer,pointer,dimension(:) :: ids |
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| 255 | integer,intent(out) :: ierr,idslen |
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| 256 | end subroutine gf_unpack1 |
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| 257 | subroutine gf_unpack2(cgrib,lcgrib,iofst,lencsec2,csec2,ierr) |
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| 258 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 259 | integer,intent(in) :: lcgrib |
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| 260 | integer,intent(inout) :: iofst |
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| 261 | integer,intent(out) :: lencsec2 |
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| 262 | integer,intent(out) :: ierr |
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| 263 | character(len=1),pointer,dimension(:) :: csec2 |
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| 264 | end subroutine gf_unpack2 |
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| 265 | subroutine gf_unpack3(cgrib,lcgrib,iofst,igds,igdstmpl, |
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| 266 | & mapgridlen,ideflist,idefnum,ierr) |
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| 267 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 268 | integer,intent(in) :: lcgrib |
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| 269 | integer,intent(inout) :: iofst |
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| 270 | integer,pointer,dimension(:) :: igdstmpl,ideflist |
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| 271 | integer,intent(out) :: igds(5) |
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| 272 | integer,intent(out) :: ierr,idefnum |
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| 273 | end subroutine gf_unpack3 |
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| 274 | subroutine gf_unpack4(cgrib,lcgrib,iofst,ipdsnum,ipdstmpl, |
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| 275 | & mappdslen,coordlist,numcoord,ierr) |
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| 276 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 277 | integer,intent(in) :: lcgrib |
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| 278 | integer,intent(inout) :: iofst |
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| 279 | real,pointer,dimension(:) :: coordlist |
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| 280 | integer,pointer,dimension(:) :: ipdstmpl |
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| 281 | integer,intent(out) :: ipdsnum |
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| 282 | integer,intent(out) :: ierr,numcoord |
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| 283 | end subroutine gf_unpack4 |
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| 284 | subroutine gf_unpack5(cgrib,lcgrib,iofst,ndpts,idrsnum, |
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| 285 | & idrstmpl,mapdrslen,ierr) |
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| 286 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 287 | integer,intent(in) :: lcgrib |
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| 288 | integer,intent(inout) :: iofst |
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| 289 | integer,intent(out) :: ndpts,idrsnum |
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| 290 | integer,pointer,dimension(:) :: idrstmpl |
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| 291 | integer,intent(out) :: ierr |
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| 292 | end subroutine gf_unpack5 |
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| 293 | subroutine gf_unpack6(cgrib,lcgrib,iofst,ngpts,ibmap,bmap,ierr) |
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| 294 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 295 | integer,intent(in) :: lcgrib,ngpts |
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| 296 | integer,intent(inout) :: iofst |
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| 297 | integer,intent(out) :: ibmap |
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| 298 | integer,intent(out) :: ierr |
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| 299 | logical*1,pointer,dimension(:) :: bmap |
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| 300 | end subroutine gf_unpack6 |
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| 301 | subroutine gf_unpack7(cgrib,lcgrib,iofst,igdsnum,igdstmpl, |
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| 302 | & idrsnum,idrstmpl,ndpts,fld,ierr) |
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| 303 | character(len=1),intent(in) :: cgrib(lcgrib) |
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| 304 | integer,intent(in) :: lcgrib,ndpts,idrsnum,igdsnum |
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| 305 | integer,intent(inout) :: iofst |
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| 306 | integer,pointer,dimension(:) :: idrstmpl,igdstmpl |
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| 307 | integer,intent(out) :: ierr |
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| 308 | real,pointer,dimension(:) :: fld |
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| 309 | end subroutine gf_unpack7 |
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| 310 | end interface |
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| 311 | |
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| 312 | have3=.false. |
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| 313 | have4=.false. |
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| 314 | have5=.false. |
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| 315 | have6=.false. |
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| 316 | have7=.false. |
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| 317 | ierr=0 |
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| 318 | numfld=0 |
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| 319 | gfld%locallen=0 |
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| 320 | nullify(gfld%list_opt,gfld%igdtmpl,gfld%ipdtmpl) |
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| 321 | nullify(gfld%coord_list,gfld%idrtmpl,gfld%bmap,gfld%fld) |
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| 322 | ! |
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| 323 | ! Check for valid request number |
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| 324 | ! |
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| 325 | if (ifldnum.le.0) then |
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| 326 | print *,'gf_getfld: Request for field number must be positive.' |
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| 327 | ierr=3 |
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| 328 | return |
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| 329 | endif |
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| 330 | ! |
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| 331 | ! Check for beginning of GRIB message in the first 100 bytes |
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| 332 | ! |
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| 333 | istart=0 |
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| 334 | do j=1,100 |
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| 335 | ctemp=cgrib(j)//cgrib(j+1)//cgrib(j+2)//cgrib(j+3) |
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| 336 | if (ctemp.eq.grib ) then |
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| 337 | istart=j |
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| 338 | exit |
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| 339 | endif |
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| 340 | enddo |
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| 341 | if (istart.eq.0) then |
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| 342 | print *,'gf_getfld: Beginning characters GRIB not found.' |
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| 343 | ierr=1 |
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| 344 | return |
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| 345 | endif |
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| 346 | ! |
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| 347 | ! Unpack Section 0 - Indicator Section |
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| 348 | ! |
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| 349 | iofst=8*(istart+5) |
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| 350 | call g2lib_gbyte(cgrib,listsec0(1),iofst,8) ! Discipline |
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| 351 | iofst=iofst+8 |
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| 352 | call g2lib_gbyte(cgrib,listsec0(2),iofst,8) ! GRIB edition number |
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| 353 | iofst=iofst+8 |
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| 354 | iofst=iofst+32 |
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| 355 | call g2lib_gbyte(cgrib,lengrib,iofst,32) ! Length of GRIB message |
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| 356 | iofst=iofst+32 |
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| 357 | lensec0=16 |
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| 358 | ipos=istart+lensec0 |
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| 359 | ! |
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| 360 | ! Currently handles only GRIB Edition 2. |
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| 361 | ! |
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| 362 | if (listsec0(2).ne.2) then |
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| 363 | print *,'gf_getfld: can only decode GRIB edition 2.' |
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| 364 | ierr=2 |
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| 365 | return |
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| 366 | endif |
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| 367 | ! |
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| 368 | ! Loop through the remaining sections keeping track of the |
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| 369 | ! length of each. Also keep the latest Grid Definition Section info. |
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| 370 | ! Unpack the requested field number. |
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| 371 | ! |
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| 372 | do |
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| 373 | ! Check to see if we are at end of GRIB message |
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| 374 | ctemp=cgrib(ipos)//cgrib(ipos+1)//cgrib(ipos+2)//cgrib(ipos+3) |
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| 375 | if (ctemp.eq.c7777 ) then |
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| 376 | ipos=ipos+4 |
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| 377 | ! If end of GRIB message not where expected, issue error |
|---|
| 378 | if (ipos.ne.(istart+lengrib)) then |
|---|
| 379 | print *,'gf_getfld: "7777" found, but not where expected.' |
|---|
| 380 | ierr=4 |
|---|
| 381 | return |
|---|
| 382 | endif |
|---|
| 383 | exit |
|---|
| 384 | endif |
|---|
| 385 | ! Get length of Section and Section number |
|---|
| 386 | iofst=(ipos-1)*8 |
|---|
| 387 | call g2lib_gbyte(cgrib,lensec,iofst,32) ! Get Length of Section |
|---|
| 388 | iofst=iofst+32 |
|---|
| 389 | call g2lib_gbyte(cgrib,isecnum,iofst,8) ! Get Section number |
|---|
| 390 | iofst=iofst+8 |
|---|
| 391 | !print *,' lensec= ',lensec,' secnum= ',isecnum |
|---|
| 392 | ! |
|---|
| 393 | ! Check to see if section number is valid |
|---|
| 394 | ! |
|---|
| 395 | if ( (isecnum.lt.1).OR.(isecnum.gt.7) ) then |
|---|
| 396 | print *,'gf_getfld: Unrecognized Section Encountered=',isecnum |
|---|
| 397 | ierr=8 |
|---|
| 398 | return |
|---|
| 399 | endif |
|---|
| 400 | ! |
|---|
| 401 | ! If found Section 1, decode elements in Identification Section |
|---|
| 402 | ! |
|---|
| 403 | if (isecnum.eq.1) then |
|---|
| 404 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 405 | call gf_unpack1(cgrib,lcgrib,iofst,gfld%idsect, |
|---|
| 406 | & gfld%idsectlen,jerr) |
|---|
| 407 | if (jerr.ne.0) then |
|---|
| 408 | ierr=15 |
|---|
| 409 | return |
|---|
| 410 | endif |
|---|
| 411 | endif |
|---|
| 412 | ! |
|---|
| 413 | ! If found Section 2, Grab local section |
|---|
| 414 | ! Save in case this is the latest one before the requested field. |
|---|
| 415 | ! |
|---|
| 416 | if (isecnum.eq.2) then |
|---|
| 417 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 418 | if (associated(gfld%local)) deallocate(gfld%local) |
|---|
| 419 | call gf_unpack2(cgrib,lcgrib,iofst,gfld%locallen, |
|---|
| 420 | & gfld%local,jerr) |
|---|
| 421 | if (jerr.ne.0) then |
|---|
| 422 | ierr=16 |
|---|
| 423 | return |
|---|
| 424 | endif |
|---|
| 425 | endif |
|---|
| 426 | ! |
|---|
| 427 | ! If found Section 3, unpack the GDS info using the |
|---|
| 428 | ! appropriate template. Save in case this is the latest |
|---|
| 429 | ! grid before the requested field. |
|---|
| 430 | ! |
|---|
| 431 | if (isecnum.eq.3) then |
|---|
| 432 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 433 | if (associated(gfld%igdtmpl)) deallocate(gfld%igdtmpl) |
|---|
| 434 | if (associated(gfld%list_opt)) deallocate(gfld%list_opt) |
|---|
| 435 | call gf_unpack3(cgrib,lcgrib,iofst,igds,gfld%igdtmpl, |
|---|
| 436 | & gfld%igdtlen,gfld%list_opt,gfld%num_opt,jerr) |
|---|
| 437 | if (jerr.eq.0) then |
|---|
| 438 | have3=.true. |
|---|
| 439 | gfld%griddef=igds(1) |
|---|
| 440 | gfld%ngrdpts=igds(2) |
|---|
| 441 | gfld%numoct_opt=igds(3) |
|---|
| 442 | gfld%interp_opt=igds(4) |
|---|
| 443 | gfld%igdtnum=igds(5) |
|---|
| 444 | else |
|---|
| 445 | ierr=10 |
|---|
| 446 | return |
|---|
| 447 | endif |
|---|
| 448 | endif |
|---|
| 449 | ! |
|---|
| 450 | ! If found Section 4, check to see if this field is the |
|---|
| 451 | ! one requested. |
|---|
| 452 | ! |
|---|
| 453 | if (isecnum.eq.4) then |
|---|
| 454 | numfld=numfld+1 |
|---|
| 455 | if (numfld.eq.ifldnum) then |
|---|
| 456 | gfld%discipline=listsec0(1) |
|---|
| 457 | gfld%version=listsec0(2) |
|---|
| 458 | gfld%ifldnum=ifldnum |
|---|
| 459 | gfld%unpacked=unpack |
|---|
| 460 | gfld%expanded=.false. |
|---|
| 461 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 462 | call gf_unpack4(cgrib,lcgrib,iofst,gfld%ipdtnum, |
|---|
| 463 | & gfld%ipdtmpl,gfld%ipdtlen,gfld%coord_list, |
|---|
| 464 | & gfld%num_coord,jerr) |
|---|
| 465 | if (jerr.eq.0) then |
|---|
| 466 | have4=.true. |
|---|
| 467 | else |
|---|
| 468 | ierr=11 |
|---|
| 469 | return |
|---|
| 470 | endif |
|---|
| 471 | endif |
|---|
| 472 | endif |
|---|
| 473 | ! |
|---|
| 474 | ! If found Section 5, check to see if this field is the |
|---|
| 475 | ! one requested. |
|---|
| 476 | ! |
|---|
| 477 | if ((isecnum.eq.5).and.(numfld.eq.ifldnum)) then |
|---|
| 478 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 479 | call gf_unpack5(cgrib,lcgrib,iofst,gfld%ndpts,gfld%idrtnum, |
|---|
| 480 | & gfld%idrtmpl,gfld%idrtlen,jerr) |
|---|
| 481 | if (jerr.eq.0) then |
|---|
| 482 | have5=.true. |
|---|
| 483 | else |
|---|
| 484 | ierr=12 |
|---|
| 485 | return |
|---|
| 486 | endif |
|---|
| 487 | endif |
|---|
| 488 | ! |
|---|
| 489 | ! If found Section 6, Unpack bitmap. |
|---|
| 490 | ! Save in case this is the latest |
|---|
| 491 | ! bitmap before the requested field. |
|---|
| 492 | ! |
|---|
| 493 | if (isecnum.eq.6) then |
|---|
| 494 | if (unpack) then ! unpack bitmap |
|---|
| 495 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 496 | bmpsave=>gfld%bmap ! save pointer to previous bitmap |
|---|
| 497 | call gf_unpack6(cgrib,lcgrib,iofst,gfld%ngrdpts,gfld%ibmap, |
|---|
| 498 | & gfld%bmap,jerr) |
|---|
| 499 | if (jerr.eq.0) then |
|---|
| 500 | have6=.true. |
|---|
| 501 | if (gfld%ibmap .eq. 254) then ! use previously specified bitmap |
|---|
| 502 | if ( associated(bmpsave) ) then |
|---|
| 503 | gfld%bmap=>bmpsave |
|---|
| 504 | else |
|---|
| 505 | print *,'gf_getfld: Previous bit-map specified,', |
|---|
| 506 | & ' but none exists,' |
|---|
| 507 | ierr=17 |
|---|
| 508 | return |
|---|
| 509 | endif |
|---|
| 510 | else ! get rid of it |
|---|
| 511 | if ( associated(bmpsave) ) deallocate(bmpsave) |
|---|
| 512 | endif |
|---|
| 513 | else |
|---|
| 514 | ierr=13 |
|---|
| 515 | return |
|---|
| 516 | endif |
|---|
| 517 | else ! do not unpack bitmap |
|---|
| 518 | call g2lib_gbyte(cgrib,gfld%ibmap,iofst,8) ! Get BitMap Indicator |
|---|
| 519 | have6=.true. |
|---|
| 520 | endif |
|---|
| 521 | endif |
|---|
| 522 | ! |
|---|
| 523 | ! If found Section 7, check to see if this field is the |
|---|
| 524 | ! one requested. |
|---|
| 525 | ! |
|---|
| 526 | if ((isecnum.eq.7).and.(numfld.eq.ifldnum).and.unpack) then |
|---|
| 527 | iofst=iofst-40 ! reset offset to beginning of section |
|---|
| 528 | call gf_unpack7(cgrib,lcgrib,iofst,gfld%igdtnum, |
|---|
| 529 | & gfld%igdtmpl,gfld%idrtnum, |
|---|
| 530 | & gfld%idrtmpl,gfld%ndpts, |
|---|
| 531 | & gfld%fld,jerr) |
|---|
| 532 | if (jerr.eq.0) then |
|---|
| 533 | have7=.true. |
|---|
| 534 | ! If bitmap is used with this field, expand data field |
|---|
| 535 | ! to grid, if possible. |
|---|
| 536 | if ( gfld%ibmap .ne. 255 .AND. associated(gfld%bmap) ) then |
|---|
| 537 | if ( expand ) then |
|---|
| 538 | allocate(newfld(gfld%ngrdpts)) |
|---|
| 539 | !newfld(1:gfld%ngrdpts)=0.0 |
|---|
| 540 | !newfld=unpack(gfld%fld,gfld%bmap,newfld) |
|---|
| 541 | n=1 |
|---|
| 542 | do j=1,gfld%ngrdpts |
|---|
| 543 | if ( gfld%bmap(j) ) then |
|---|
| 544 | newfld(j)=gfld%fld(n) |
|---|
| 545 | n=n+1 |
|---|
| 546 | else |
|---|
| 547 | newfld(j)=0.0 |
|---|
| 548 | endif |
|---|
| 549 | enddo |
|---|
| 550 | deallocate(gfld%fld); |
|---|
| 551 | gfld%fld=>newfld; |
|---|
| 552 | gfld%expanded=.true. |
|---|
| 553 | else |
|---|
| 554 | gfld%expanded=.false. |
|---|
| 555 | endif |
|---|
| 556 | else |
|---|
| 557 | gfld%expanded=.true. |
|---|
| 558 | endif |
|---|
| 559 | else |
|---|
| 560 | print *,'gf_getfld: return from gf_unpack7 = ',jerr |
|---|
| 561 | ierr=14 |
|---|
| 562 | return |
|---|
| 563 | endif |
|---|
| 564 | endif |
|---|
| 565 | ! |
|---|
| 566 | ! Check to see if we read pass the end of the GRIB |
|---|
| 567 | ! message and missed the terminator string '7777'. |
|---|
| 568 | ! |
|---|
| 569 | ipos=ipos+lensec ! Update beginning of section pointer |
|---|
| 570 | if (ipos.gt.(istart+lengrib)) then |
|---|
| 571 | print *,'gf_getfld: "7777" not found at end of GRIB message.' |
|---|
| 572 | ierr=7 |
|---|
| 573 | return |
|---|
| 574 | endif |
|---|
| 575 | ! |
|---|
| 576 | ! If unpacking requested, return when all sections have been |
|---|
| 577 | ! processed |
|---|
| 578 | ! |
|---|
| 579 | if (unpack.and.have3.and.have4.and.have5.and.have6.and.have7) |
|---|
| 580 | & return |
|---|
| 581 | ! |
|---|
| 582 | ! If unpacking is not requested, return when sections |
|---|
| 583 | ! 3 through 6 have been processed |
|---|
| 584 | ! |
|---|
| 585 | if ((.NOT.unpack).and.have3.and.have4.and.have5.and.have6) |
|---|
| 586 | & return |
|---|
| 587 | |
|---|
| 588 | enddo |
|---|
| 589 | |
|---|
| 590 | ! |
|---|
| 591 | ! If exited from above loop, the end of the GRIB message was reached |
|---|
| 592 | ! before the requested field was found. |
|---|
| 593 | ! |
|---|
| 594 | print *,'gf_getfld: GRIB message contained ',numlocal, |
|---|
| 595 | & ' different fields.' |
|---|
| 596 | print *,'gf_getfld: The request was for the ',ifldnum, |
|---|
| 597 | & ' field.' |
|---|
| 598 | ierr=6 |
|---|
| 599 | |
|---|
| 600 | return |
|---|
| 601 | end |
|---|
| 602 | |
|---|