PTDISP dataset frame [keywords]
PTDISP displays data from records in a point data file. The SELECT keyword defines which records to match and the PARAM keyword defines which parameters in the matching records to display. If PTDISP has started to plot data, you can stop it by pressing Alt Q.
If you use the range format for the SELECT keyword and bval is less than eval, all values between and including bval and eval are selected. For example, if you specify SELECT='LON -177 177', the longitude values -177, -176, . . , 176, 177 are selected. If bval is greater than eval, all values greater than bval or less than eval, including bval and eval, are selected. For example, if you specify SELECT='LON 177 -177', the longitude values 177, 178, 179, 180, -179, -178 and -177 are selected. This feature also allows you to select only wind directions from northwest to northeast with SELECT='DIR 315 45'.
You can assign output plot color based on the parameter's values by using the COLOR keyword format color[min-maxBinc], where color is the beginning graphics color level, min and max indicate the range of parameter values to color-code, and inc is the increment (the dash means "to" and the B means "by"). For example, when plotting integer values, COLOR=2[30-59B10] plots values 30-39 in level 2, values 40-49 in level 3, and values 50-59 in level 4. Values less than 30 are in level 1, and values greater than 59 are in level 5. When plotting floating point values (e.g., FORMAT=F5.2), COLOR=2[30-59.99B10] plots values 30.00-39.99 in level 2, values 40.00-49.99 in level 3, and values 50.00-59.99 in level 4. Values less than 30.00 are in level 1, and values greater than 59.99 are in level 5. Also, when plotting color-coded wind flags (PAR=WIND with FORMAT=FLAG), the units of the min and max values are knots, even if you specify PAR=WIND[MPS].
Use the FORMAT keyword options below to format output based on FORTRAN designators for data output:
Designator | Description |
---|---|
A | character |
I | integer |
F | floating point |
E | exponential |
To specify a parameter's output format, use a designator followed by a number. For example, I4 specifies an integer of up to four digits; A4 specifies up to four characters, which is the maximum; 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 plotted.
Use the K format to "clip" leading integer digits and drop the decimal portion of an integer or floating point value. Follow the K with a number to specify the number of integer digits to display. For example, if a pressure value is 1016.26 and you specify FORMAT=K3, 016 is plotted. If you also specify MULTIPLY=10, 163 is plotted.
Specify FORMAT=SYMB to translate weather report types (R-, S+, for example) into equivalent weather symbols. Only the first type in the report is plotted.
Specify FORMAT=WXCM, WXCA, WPCM or WPCA to translate WMO numeric codes into equivalent weather symbols. The table below shows the ISFC and SYN MD file schema parameter combinations that correspond to each format.
If you specify FORMAT=VECT or FLAG, you must also specify PARAM=WIND, which requests wind speed (SPD) and direction (DIR) from the point file. The VECT format produces a wind vector display. The FLAG format produces a wind flag display. The vector or flag is placed at the center plot position; using the OFFSET keyword has no effect.
Wind flag symbols use triangular flags, and long and short lines, or barbs, to represent wind speed. For example, the wind flag shown here represents a wind speed of 75 knots or 37.5 meters/second.
A default title is constructed using the information specified with the PARAM and SELECT keywords. For example, if your command contains the keywords PARAM=T[F] TD[C] SELECT='DAY 96325; TIME 12; TYPE 0', the default title is: T[F] TD[C] DAY=96325 TIME=12 TYPE=0. Use the TITLE keyword if you want to choose a different title.
When using the SELECT and PARAM keywords, you can use the following units:
The PARAM keyword contains the parameters to plot. The list can contain native and/or computed parameters.
Native parameters are those stored in the point file. They are specified in the PARAM keyword list in the format parameter[unit], where parameter is the parameter name in the file, and [unit] is the output units, which are optional but must be in square brackets if specified.
Computed parameters do not exist in the point file but are derived with a mathematical expression. They are specified in the PARAM keyword list in the format 'parameter[unit]=expression', where parameter is the user-defined parameter name; [unit] is the label units, which are optional but must be in square brackets if specified; and expression is the mathematical expression consisting of math operators and one or more native parameters defined in the Pn keywords.
The table below lists the math operators valid in the computed parameter expression in the PARAM keyword.
To compute a power of ten, such as 102 or 10-3 in the math expression of a computed parameter in the PARAM keyword, specify it in either the 1epower or 10**(power) format. For example, both 1e-5 and 10**(-5) represent 10-5. You must include the parenthesis with 10**(-5) for it to be interpreted correctly.
The following character limits exist for the PARAM keyword:
When using point/MD files with CYD (ccyyddd) date units (e.g., FO14, IRAB, ISEN, ISFC, ISHP, PIRP and SYN schema MD files created with McIDAS-XCD 7.5 and later), commands PTCON, PTCOPY, PTDISP and PTLIST default to the current year if you don't specify a four-digit year and the nearest century if you specify only the last two digits of the year. For example, if the file uses CYD units for the DAY parameter and its value is 2004260, then you can specify the DAY in the SELECT keyword as 2004260 or 04260. If the current year is 2004, you can also specify it as 260. Use the PTLIST command with FORM=PARAM to list the file's parameters and units.
The PTCON, PTCOPY, PTDISP and PTLIST commands continue to work with point/MD files using the old SYD (ssyyddd) date units (e.g., FO14, IRAB, ISEN, ISFC, ISHP, PIRP and SYN schema MD files created with versions of McIDAS-XCD prior to 7.5), with the following exception: If you want to specify DAY in the SELECT keyword and the ss portion of the MD file's DAY value is nonzero, then you must specify the units with DAY in the SELECT keyword. For example, if the MD file uses SYD units for DAY and its value is 7197240, then it must appear as SELECT='DAY[SYD] 7197240'. If the MD file uses SYD units for DAY but has a zero (blank) ss value, you don't have to specify the units in the SELECT keyword. For example, if the MD file uses SYD units for DAY and its value is 97240 then it can appear as either SELECT='DAY 97240' or SELECT='DAY[SYD] 97240'.
PTDISP SURFACE/ISFC SELECT='TIME 12' PARAM=T
This entry plots 12 UTC temperatures from the most recent point file in dataset SURFACE/ISFC. The temperatures are plotted using the navigation of the current frame and are in the units and format that the file uses for storing temperature.
PTDISP SURFACE/SYNOPTIC SELECT='TIME 18 ; DAY 96001' PARAM=T[C] FORMAT=I3 DECLUT=NO LAT=-40 -40 LON=-90 90 SLAT=-40 PRO=CONF TITLE='Antarctic Temperatures (deg C) at 18 UTC on 1 Jan 1996'
This entry plots 18 UTC temperatures in degrees Celsius from the point file storing the data for day 96001 in dataset SURFACE/SYNOPTIC. The temperatures are plotted as integers of up to three digits over a southern hemisphere map centered near the South Pole. All matching temperatures are plotted since DECLUT=NO is specified. The default title below the plot is replaced with the text Antarctic Temperatures (deg C) at 18 UTC on 1 Jan 1996.
PTDISP SURFACE/ISFC.5 OPP SELECT='TIME 12 ; T[F] 20 29' PARAM=T[F] FORMAT=I3 MAP=USA
This entry plots 12 UTC temperatures between 20 and 29 degrees Fahrenheit from the point file in position 5 of dataset SURFACE/ISFC. The temperatures are plotted on the frame opposite the current frame and are in degrees Fahrenheit over a map of the United States. The specified FORMAT keyword plots the temperatures as integers of up to three digits.
PTDISP SURFACE/ISFC.10 SELECT='TIME 17' PARAM=WIND T[F] TD[F] PSL[MB] ID FORMAT=FLAG I3 I3 K3 MULTIPLY=X X X 10 LSIZE=11 6 6 6 5 COLOR=7 5 4 3 2 OFFSET=0 0 -8 -13 3 -13 -8 3 3 3 MAP=MID TITLE='US Station Plot, 1700Z'
This entry displays a station plot of 17 UTC data from the point file in position 10 of dataset SURFACE/ISFC. The station plot includes wind flags, temperatures (in degrees Fahrenheit), dew point temperatures (in degrees Fahrenheit), altimeter settings (in millibars) and station IDs over a map of the Midwest. The LSIZE, COLOR and OFFSET keywords determine the plot size, graphics color level and offset from the center plot position of each of the five parameters. The altimeter settings are displayed in the standard meteorological format by using the K format to "clip" all but the last three integer digits after the observed values are multiplied by 10 with the MULTIPLY keyword. For example, an observed value of 1002.71 is displayed as 027; an observed value of 999.33 is displayed as 993.
PTDISP RAOB/MANDATORY.8 SELECT='LEV 850 ; TIME 0' PARAM=WIND T[C]
TD[C] FORMAT=VECT I3 I3 LSIZE=12 7 7 COLOR=7 5 4 OFFSET=0 0 -12 2 4 2 MAP=OK
PAN=1
PTDISP RAOB/MANDATORY.8
SELECT='LEV 500 ; TIME 0' PARAM=WIND T[C] TD[C] FORMAT=VECT I3 I3 LSIZE=12
7 7 COLOR=7 5 4 OFFSET=0 0 -12 2 4 2 MAP=OK PAN=2
PTDISP SURFACE/ISFC.8
SELECT='TIME 0' PARAM=WIND T[C] TD[C] FORMAT=VECT I3 I3 LSIZE=12 7 7 COLOR=7
5 4 OFFSET=0 0 -12 2 4 2 MAP=OK PAN=2 2 1
These entries create a three-panel display of 00 UTC wind vectors, temperatures and dew point temperatures from the point files in position 8 of datasets RAOB/MANDATORY and SURFACE/ISFC. The first entry displays the 850 millibar data in the upper-left quarter of the frame. The second entry displays the 500 millibar data in the upper-right quarter of the frame. The third entry displays the surface data in the bottom half of the frame. The FORMAT, LSIZE, COLOR and OFFSET keywords determine the format, plot size, graphics color level and offset from the center plot position of each of the three parameters.
PTDISP RTPTSRC/SFCHOURLY SEL='DAY #Y;TIME 18' PAR='DELP[MB]=P2-P1' P1=PSL[MB] P2=PSL[MB] 'TIME 21' FORMAT=F4.1 NAV=C
This entry plots today's 18 UTC to 21 UTC pressure change in millibars using the navigation of the current frame. The data is taken from the most recent point file in dataset RTPTSRC/SFCHOURLY.
PTDISP RTPTSRC/UPPERMAND SEL='DAY #Y;TIME 12' MAP=USA PARAM='THIK[M]=(287/9.8)*((P1+P2)/2)*LOG(1000/500)' P1=T[K] 'P 1000' P2=T[K] 'P 500'
This entry plots 1000-500 mb thickness in meters at 12 UTC today on a map of the United States. The thickness values are calculated using the equation in the PARAM keyword, known as the Hypsometric Equation.
PTDISP RTPTSRC/SFCHOURLY SEL='DAY #Y; TIME 20' MAP=USA PARAM=T[F] FORMAT=I4 COLOR=2[20-89B10]
This entry plots today's 20 UTC temperatures on a map of the United States. The temperatures are color coded: less than 20°F in graphics color level 1, 20-29°F in level 2, 30-39°F in level 3, 40-49°F in level 4, 50-59°F in level 5, 60-69°F in level 6, 70-79°F in level 7, 80-89°F in level 8, and 90°F and greater in level 9.
PTDISP RTPTSRC/SFCHOURLY SEL='DAY #Y; TIME 15' MAP=IL PARAM=WIND[KTS] FORMAT=FLAG COLOR=2[1-20B5]
This entry plots today's 15 UTC wind flags on a map of Illinois. The flags are color coded by speed: less than 1 knot in graphics color level 1, 1-5 knots in level 2, 6-10 knots in level 3, 11-15 knots in level 4, 16-20 knots in level 5, and greater than 20 knots in level 6. Note that each flag symbol may appear in two different colors because the speeds are rounded to the nearest five knot increment (i.e., 2.5-7.4 knot speeds are displayed as 5 knot flags, 7.5-12.4 knot speeds are displayed as 10 knot flags, 12.5-17.4 knot speeds are displayed as 15 knot flags, etc.). Thus, 5 knot flags can be in graphics color level 2 or 3, 10 knot flags can be in level 3 or 4, 15 knot flags can be in level 4 or 5, etc.