GRDINFO

Lists, modifies, or statistically analyzes grid point values.

Formats

GRDINFO sdataset EDIT ddataset [keywords]
GRDINFO sdataset HIST [keywords]
GRDINFO sdataset LIST [keywords]
GRDINFO sdataset STAT [keywords]

Parameters

sdataset	source ADDE dataset name and absolute position; specify one of the following formats:
		group/descriptor.position alias.position
	use only positive integers or ALL (all positions) for position (no default for group/descriptor or alias; default=ALL for position)
EDIT	modifies grid point values and copies the new grid to ddataset
HIST	displays histogram for grid point values
LIST	lists grid point values
STAT	displays statistical analysis for grid point values; statistics include the minimum and maximum values, mean, and standard deviation (default)
ddataset	destination ADDE dataset name and absolute position; specify one of the following formats:
		group/descriptor.position alias.position
	use only positive integers for position

Search Keywords

DAY=	d1 . . dn	selects grids with the specified days
DRAnge=	bday eday inc	selects grids in the range of days bday through eday, incremented by inc days (no default for bday; eday default=bday; inc default=1)
ENSemble=	e1 . . en	selects grids with the specified ensemble numbers; each ensemble number must include a + or - sign, e.g., -1 -0 +0 +1
FDAy=	selects grids with the specified forecast day; a grid's forecast day is determined by adding the forecast hour to the day and time; for example, a 12 UTC grid from day 2000100 with a forecast hour of 72 has a forecast day of 2000103; you cannot use FDAY with the FHOUR, FRANGE or MATH keyword
FHOur=	h1 . . hn	selects grids with the specified forecast hours; you cannot use FHOUR with the FRANGE, FDAY or FTIME keyword
FRANGe=	bhr ehr inc	selects grids in the range of forecast hours bhr through ehr, incremented by inc hours; you cannot use FRANGE with the FHOUR, FDAY or FTIME keyword (no default for bhr; ehr default=bhr; inc default=1)
FTIme=	selects grids with the specified forecast time; a grid's forecast time is determined by adding the forecast hour to the time; for example, a 12 UTC grid with a forecast hour of 18 has a forecast time of 6 on the following day; you cannot use FTIME with the FHOUR, FRANGE or MATH keyword
GPRo=	g1 . . gn	selects grids with the specified projection, for example, MERC, PS, LAMB, EQUI
GRIB=	geo par model level selects grids with the specified GRIB codes; the four values are the geographic, parameter, model and level codes that can be listed with GRDLIST FORM=ALL; values specified as an X (a placeholder) or not specified at all will match any GRIB code
GRId=	bgrid egrid	selects grids bgrid through egrid in the grid file specified in the dataset parameter; enter a grid number or LAST (last grid) for bgrid and egrid; see the Remarks (no default for bgrid; egrid default=bgrid)
LEV=	l1[u1] . . ln[un]	selects grids with the specified levels and units, e.g., SFC, 850[MB], 5000[M]; units are optional but must be in square brackets if specified; if [MB] or [HPA] is specified for units then grids with either of those units are selected
PARam=	p1 . . pn	selects grids with the specified parameters, for example, T, Z, RH; do not use with the DERIVE keyword; see the Remarks
SRC=	s1 . . sn	selects grids with the specified sources, for example, MDX, GFS, ETA
TIMe=	t1 . . tn	selects grids with the specified times
TRAnge=	btim etim inc	selects grids in the range of times btim through etim, incremented by inc (no default for btim; etim default=btim; inc default=1, meaning one hour)

Derived Grid Keywords

DERive=	selects the component grids needed to derive a grid with the specified parameter, for example, DST or VOR; the grid listed with the HIST, LIST, or STAT parameters does not exist, but the components needed to derive such a grid do; do not use with the PARAM keyword; see the Remarks
MERidional=	YES	adds a correction term to account for the convergence of longitude lines at the poles
	NO	does not add a correction term; only valid with DERIVE=ABV, DSH, DST, DVG, or VOR; see the Remarks (default)
PLAnet=	planet for which derive calculations are done; valid options are MERCURY, VENUS, EARTH, MARS, JUPITER, SATURN, NEPTUNE, URANUS (default=EARTH)

Mathematical Operations Keywords

Gn=	'clause1; clause2; . .; clausen' grids to be used with the MATH keyword; separate select clauses with semicolons; single quotes are mandatory; specify clause using the following format: searchkeyword value valid options for searchkeyword are DAY, FHOUR, GPRO, GRID, LEV, PARAM, SRC, TIME; you can specify numbers between 1 and 99 in the keyword name (G1, G2, . . , G99); see the Remarks
INFo=	'text'		string placed in the header of the copied grid when the MATH keyword is used; maximum of 48 characters
MATh=	'expression'		mathematical operation to perform on the grids specified with the Gn keywords; single quotes are mandatory; see the Remarks
NEWpar=	param punit level lunit src header information for the grid copied with the MATH keyword; parameter and level values, and associated units
		param	grid parameter; four characters maximum (default=MATH)
		punit	units of grid parameter; four characters maximum (default=NONE)
		level	grid level (default=from grid)
		lunit	units of grid level; two characters maximum (default=from grid)
		src	grid source; four characters maximum (default=from grid)

Grid Point Selection Keywords

COL=	bcol ecol	range of columns to list or edit; specify MAX for the last column in the grid (default=1 MAX for the STAT and HIST options; default=1 bcol for the LIST and EDIT options)
LAT=	lat1 lat2	range of latitudes to list or edit; range must be south to north (default=grid latitude extents)
LON=	lon1 lon2	range of longitudes to list or edit; range must be east to west (default=grid longitude extents)
RANge=	bval eval	range of grid point values to list or edit; bval can be MISS for missing values (default=all values)
	MISS	list or edit grid points with missing values
ROW=	brow erow	range of rows to list or edit; specify MAX for the last row in the grid (default=1 MAX for the STAT and HIST options; default=1 brow for the LIST and EDIT options)

EDIT Option Keywords

DEL=	YES	delete the destination grid file before copying the edited grid; see the Remarks
	NO	do not delete the destination grid file (default)
DGRid=	beginning grid number in the destination grid file to place the edited grids; this keyword may overwrite existing grids; see the Remarks (default=append after the last grid in the grid file)
MAXgrd=	maximum number of grids the newly created destination grid file can store; see the Remarks (default=1000)
TITLE=	'text'	title of the newly created destination grid file; 32 characters maximum; see the Remarks
VALue=	num	value to assign to grid points specified with the grid point selection keywords
	MISS	assigns a missing data value to the specified grid points

Output Keywords

BINsize=	increment, or bin width, for the histogram; valid only with the HIST option (default=from sdataset)
BYTecount=	YES	lists the number of bytes received from the server
	NO	does not list the number of bytes (default)
FORmat=	output format for grid point values; if multiple parameters are requested, FORMAT cannot be specified; see the Remarks
NUM=	number of grids matching the criteria defined with the search keywords to list or edit; for example, if you specify NUM=50, the first 50 grids matching the search keywords are used (default=1)
	ALL	use all grids matching the search keywords
PUNit=	units to assign to the pressure grids that are output; the valid options are MB or HPA and will be used regardless of which of the two units appear in the source grid (default=units in source grids)
SUBsect=	slat nlat elon wlon incrow inccol geographic region to subsect from the source grid, and row and column reduction intervals to use within the subsect region, where:
	slat, nlat		southern and northern latitudes of the subsect region
	elon, wlon		eastern and western longitudes of the subsect region (slat, nlat, elon, wlon defaults=source grid bounds)
	incrow, inccol		row and column reduction intervals; 1 means use every row/column of grid points in the subsect region, 2 means use every other row/column, etc.; when subsecting a conformal projection grid, the incrow and inccol values must be the same (default=1 for both)
	Note: If the source grid is a McIDAS grid, you can subsect it by row and column instead of latitude and longitude. To do so, specify row and column numbers instead of latitudes and longitudes in the first four parameters, and specify ROWCOL as the seventh parameter. For example, SUBSECT=10 40 80 160 1 2 ROWCOL uses rows 10, 11, 12, ..., 40 and columns 80, 82, 84, ..., 160 for the subsect region. (If you don't include the ROWCOL at the end, it will treat 10 and 40 as latitudes, and 80 and 160 as longitudes.)
UNIt=	units to list for grid point values; not valid if multiple parameters are requested with the PARAM keyword (default=from grid header)

Remarks

Individual grids are stored in grid files. Each dataset position points to a single grid file. GRDINFO lists or edits individual grid point values in one or more grid files in a dataset. Use the search keywords to limit grid selection.

Use the RANGE, LAT and LON, and ROW and COL keywords to limit the selection of grid points. Using a combination of these grid point selection keywords limits grid points to those that meet all the specified criteria.

More than one grid can be altered using the EDIT option; however, only one value can be assigned to modify all the grids.

If you specify DEL=YES or a position number of a nonexistent grid file in the ddataset parameter, the edited grids are copied into a newly created grid file with the attributes specified in keywords MAXGRD and TITLE.

Using the DGRID keyword may result in grids being overwritten in the destination grid file. For example, if the destination grid file has 50 grids (in grids 1 to 50) and you specify NUM=10 DGRID=25, the edited grids will overwrite grids 25 to 34 in the destination grid file.

The GRID keyword copies grids from the grid file specified with the sdataset position number; the default position value, ALL, is not valid. When using the GRID keyword, do not specify additional search keywords, PARAM, LEV, DAY, etc., or NUM.

When using the DERIVE keyword with the LIST, HIST, and STAT options, GRDINFO lists information for a virtual grid: a grid that could be derived. The command searches for grids with components needed to derive a grid with the specified parameter. Only one derived parameter can be specified at a time, but you can request multiple grids, by specifying multiple levels or times, for example. Use GRDCOPY with the DERIVE keyword to create derived grids.

Use the FORMAT keyword options below to format output based on FORTRAN designators for data output:

Designator	Description
I	integer
F	floating point
E	exponential

To specify a parameter's output format, use a designator followed by a positive number. For example, I4 specifies an integer of up to four digits; I6.4 specifies an integer of up to six digits and will add leading zeros if necessary to get to four digits; F10.1 specifies a floating point decimal of up to 10 digits (including the decimal point) with one digit to the right of the decimal; E10.3 specifies an exponential number of up to 10 characters (including the decimal point and the four-character exponential flag) with three digits to the right of the decimal. Specify an X to use the parameter's default format. If the specified integer or floating point format is too small for the parameter's values, a series of asterisks (***) is displayed.

Examples

GRDINFO GFS/12

This entry lists the statistics for the first grid in the first grid file in dataset GFS/12. The statistics include the minimum and maximum values, mean, and standard deviation.

GRDINFO RT/GRID.10 HIST PARAM=T LEV=850 FHOUR=12

This entry displays the histogram of the 12-hour forecast, 850 mb temperature grid in position 10 of dataset RT/GRID.

GRDINFO GRIDS/ETA.1 DERIVE=SPD LEV=500 FHOUR=48

This entry lists the statistics for a wind speed grid that could be derived from 500 mb, 48-hour forecast time component grids in position 1 of dataset GRIDS/ETA.

GRDINFO CASEA.21 LIST PARAM=T LEV=700 FHOUR=24 ROW=15 COL=30 40 UNIT=C FORMAT=F5.1

This entry lists the temperature values stored in columns 30 through 40 of row 15 of a 24-hour forecast, 700 mb temperature grid in position 21 of the dataset with the alias name CASEA. The temperatures are listed in degrees Celsius. The temperature output is formatted as real numbers containing up to five digits (including the decimal point) with one digit to the right of the decimal point.

GRDINFO BLIZZARD/GFS.8000 EDIT BLIZZARD/EDIT.4003 VALUE=MISS LAT=40 45 LON=90 95 DERIVE=VOR LEV=500 FHOUR=48 DGRID=15

This entry creates a derived grid of relative vorticity using the 48-hour forecast, 500 mb u- and v- wind component grids in position 8000 of the dataset BLIZZARD/GFS. The new grid is placed in grid number 15 in position 4003 of the dataset BLIZZARD/EDIT, overwriting all pre-existing data. The values of grid points between 40° and 45° latitude and between 90° and 95° longitude are changed to missing data values (MISS).

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