orbit [ parameter=value ... ] [ outputfile ]
Parameters are: master_file, satellite, sensor, pass_date, start_time, duration, var_name, line_color.
orbit generates a TeraScan metafile dataset that includes the outline of the satellite data frame, the satellite subtrack line, and one minute interval lines. This metafile can be displayed using the TeraScan XVU Overlay Metafiles function.
To produce a complete coverage map the base map should be large, e.g., 1024 lines by 1280 samples with a pixel size of 6-8 kilometers or 512 lines by 640 samples with a pixel size of 12-16 kilometers. This is illustrated in the examples.
The star in the corner of the orbit map indicates the first sample of the first line of the telemetry frame.
There is exactly one output TeraScan metafile dataset.
This is the file name of the master dataset. The earth-location transform of the master dataset is used to convert latitude and longitude coordinates to line and sample coordinates during the metafile-generation process.
Valid responses are any TeraScan dataset that contains an earth transform. The default is Master.
This is the satellite name. It must be entered in lower case. Valid responses are names of the non-geostationary satellites defined in the file $REFDATA/satel/SATSETUP. There is no default.
This is the sensor name entered in lower case. Valid responses are the sensors defined in the file $REFDATA/satel/SATSETUP. The default is the first sensor defined for the user-specified satellite.
This is the start date for the orbital coverage map. Any valid date is allowed. See formats. The default is today's date.
This is the start time for the orbit coverage drawing. The valid response is any valid time. See formats. There is no default.
This is the time duration of the orbit map coverage. The valid range is [00:05:00, 00:12:00]. The default is 00:12:00.
OPTIONAL. This is the name of the output variable that contains the metafile data. This name is unimportant unless the output variable will be copied to another dataset that already contains a variable with the name pass_cover. In this case, var_name can be changed to avoid a name conflict.
Valid responses are any strings no longer than 12 characters. The default is pass_cover.
OPTIONAL. This is the color index for the metafile data. This index allows different portions of a metafile to have a unique color. It is normally used in special applications that involve combining multiple metafile datasets.
The valid range is [0, 255]. The default is 1.
This example illustrates an orbit coverage map superimposed on the world coastline map.
[1] % master output file : char(75) ? [Master] BIG_MASTER projection : char(13) ? rect center_lat : char(15) ? 30 30 N center_lon : char(15) ? 91 W num_lines : int ? 512 num_samples : int ? 512 pixel_width : real ? [1.1132] 16 pixel_height : real ? [1.1132] 16 rotate_angle : real ? [0] [2] % orbit output_file : char(75) ? BIG_ORBIT master_file : char(75) ? [Master] BIG_MASTER satellite : char(11) ? noaa-9 sensor : char( 5) ? [avhrr] pass_date : char(15) ? [89/08/03] 88 09 13 start_time : char(15) ? 21:16:00 duration : char(15) ? [00:12:00] [3] % coast output_file : char(75) ? [Coast] BIG_COAST master_file : char(75) ? [Master] BIG_MASTER reduce_factor : int ? 1 coast_file : char(75) ? [wdb2.cil] [4] % const2d output_file : char(75) ? BIG_SCREEN master_file : char(75) ? [ ] BIG_MASTER var_type : char( 6) ? byte var_value : real ? [0]
Last Update: $Date: 1998/05/29 20:15:10 $