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vg6d_transform manpage

dcesari edited this page Oct 5, 2015 · 1 revision

Synopsis

Usage: vg6d_transform [options] inputfile outputfile

Description

Gridded-field to gridded-field transformation application. It reads grib edition 1 and 2 and gdal-supported formats and zooms, interpolates or regrids data according to optional arguments. The whole input data file is read and organized in memory, transformed, and written on output. So it is possible to perform multi-field processing like wind component transformation, but memory constraints limit the number of input fields. The output file is specified in the form [output_driver:[output_template:]]pathname, when output_driver is grib_api, output_template may specify a file contaning a grib message to be used as a template for the output file.

Options

-v STRING, --trans-type=STRING

transformation type: 'inter' for interpolation, 'boxinter' for statistical interpolation on boxes, 'zoom' for zooming, 'boxregrid' for resolution reduction, 'metamorphosis' for keeping the same grid but changing e.g. the component flag, 'none' for no transformation (input/output only) [default=none]

-z STRING, --sub-type=STRING

transformation subtype, for inter: 'near', 'bilin', for boxinter and boxregrid: 'average', 'stddev', 'max', 'min', for zoom: 'index', 'coord', 'coordbb', 'projcoord', for metamorphosis: 'all', 'maskvalid', 'maskinvalid', 'invalidset' [default=near]

--extrap

enable extrapolation outside input grid, it works only for 'inter' transformations, use with care

-u STRING, --type=STRING

projection and parameters of interpolated grid: it is a string as 'regular_ll', 'rotated_ll', 'UTM' [default=regular_ll]

-i INT, --nx=INT

number of nodes along x axis on interpolated grid [default=31]

-l INT, --ny=INT

number of nodes along y axis on interpolated grid [default=31]

-m REAL, --x-min=REAL

x coordinate of the lower left corner of interpolated grid (degrees or meters) [default=0.00000000]

-o REAL, --y-min=REAL

y coordinate of the lower left corner of interpolated grid (degrees or meters) [default=30.0000000]

-n REAL, --x-max=REAL

x coordinate of the upper right corner of interpolated grid (degrees or meters) [default=30.0000000]

-p REAL, --y-max=REAL

y coordinate of the upper right corner of interpolated grid (degrees or meters) [default=60.0000000]

-n REAL, --x-off=REAL

x coordinate offset (also known as false easting) in interpolated grid [default=0.00000000]

-p REAL, --y-off=REAL

y coordinate offset (also known as false northing) in interpolated grid [default=0.00000000]

--utm-zone=INT

zone number for UTM projections [default=32]

-q REAL, --latitude-south-pole=REAL

latitude of south pole for rotated grid [default=-32.5000000]

-r REAL, --longitude-south-pole=REAL

longitude of south pole for rotated grid [default=10.0000000]

-s REAL, --angle-rotation=REAL

angle of rotation for rotated grid [default=0.00000000]

-a REAL, --ilon=REAL

longitude of the southwestern zooming/bounding box corner [default=0.00000000]

-b REAL, --ilat=REAL

latitude of the southwestern zooming/bounding box corner [default=30.0000000]

-c REAL, --flon=REAL

longitude of the northeastern zooming/bounding box corner [default=30.0000000]

-d REAL, --flat=REAL

latitude of the northeastern zooming/bounding box corner [default=60.0000000]

--ix=INT

x-index of the southwestern zooming corner [default=1]

--iy=INT

y-index of the southwestern zooming corner [default=1]

--fx=INT

x-index of the northeastern zooming corner [default=31]

--fy=INT

y-index of the northeastern zooming corner [default=31]

--radius=REAL

radius of stencil in gridpoint units, fractionary values accepted, for 'stencilinter' interpolation

--maskbounds=REAL[,REAL...]

comma-separated list of boundary values for defining subareas according to values of mask, for 'metamorphosis:maskvalid' transformation or for setting a constant value for metamorphosis:invalidset transformation

-f INT, --npx=INT

number of nodes along x axis on input grid, over which to apply function for boxregrid [default=4]

-g INT, --npy=INT

number of nodes along x axis on input grid, over which to apply function for boxregrid [default=4]

--trans-level-type=INT[,INT...]

type of input and output level for vertical interpolation in the form intop,inbot,outtop,outbot, from grib2 table; inbot and outbot can either be empty (single surface) or equal to the corresponding top value (layer between 2 surfaces)

--trans-level-list=INT[,INT...]

list of output levels (or top surfaces) for vertical interpolation, the unit is determined by the value of level-type and taken from grib2 table

--trans-botlevel-list=INT[,INT...]

list of output bottom surfaces for vertical interpolation, the unit is determined by the value of level-type and taken from grib2 table

--rounding

simplifies volume, merging similar levels and timeranges

--coord-file=STRING

file in shp format with coordinates of polygons, required for maskgen transformation or file in grib format providing vertical coordinate of input data for vertical interpolation

--coord-format=STRING

format of coord file (shp or grib_api)

--output-format=STRING

format of output file, in the form 'name[:grid_definition]'; 'grib_api' for gridded output in grib format, grid_definition is the path name of a grib file in which the first message is used as a template for defining the output grid; if this option includes a grid_definition, --type argument &c. are ignored, otherwise --type &c. define the output grid [default=grib_api]

-e, --a-grid

interpolate U/V points of an Arakawa C grid on the corresponding T points of an Arakawa A grid

-t INT, --component-flag=INT

wind component flag in interpolated grid (0/1) [default=0]

--time-definition=INT

time definition for imported volume, 0 for reference time (more suitable for presenting forecast data) and 1 for verification time (more suitable for comparing forecasts with observations) [default=0]

--dup-mode=INT

behavior in case of duplicated input metadata: 0=overwrite fields, 1=merge fields taking into account missing data and with priority to the second field [default=0]

--comp-stat-proc=STRING

statistically process data with an operator specified in the form [isp:]osp where isp is the statistical process of input data which has to be processed and osp is the statistical process to apply and which will appear in output timerange; possible values for isp and osp are 0=average, 1=accumulated, 2=maximum, 3=minimum, 254=instantaneous, but not all the combinations make sense; if isp is not provided it is assumed to be equal to osp [default=]

--comp-step=STRING

length of regularization or statistical processing step in the format 'YYYYMMDDDD hh:mm:ss.msc', it can be simplified up to the form 'D hh' [default=0000000001 00:00:00.000]

--comp-start=STRING

start of statistical processing interval, an empty value means take the initial time step of the available data; the format is YYYY-MM-DD HH:MM [default=]

--comp-full-steps

compute statistical processing by differences only on intervals with forecast time equal to a multiple of comp-step, otherwise all reasonable combinations of forecast times are computed

--display

briefly display the data volume imported and exported, warning: this option is incompatible with output on stdout.

--output-variable-list=STRING

list of data variables you require in output; if they are not in input they will be computed if possible. The output_variable_list is expressed in the form of a comma-separated list of B-table alphanumeric codes, e.g. 'B13011,B12101' [default=]

-h, --help

show an help message and exit

--version

show version and exit

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