How To: Create minimum bounding rectangle arc for ARCDFAD DSnnnP coverage
You can use GENERATE with the LINE subcommand to create the Minimum Bounding Rectangle (MBR) for a DSnnnP coverage in preparation for ARCDFAD conversion.
Determine the lowest XMIN and YMIN between the L and P coverages, and the highest XMAX and YMAX between the coverages. You can automate this process with AML.
/* EXTENTS.AML /* /* USAGE: &RUN EXTENTS <cover_1,cover_2,...,cover_n> /* /* PURPOSE: This AML determines the lowest XMIN, the lowest YMIN, /* the highest XMAX, and the highest YMAX among a group of /* coverages. /* /* NOTES: The <cover_1,cover_2,...,cover_n> argument has a limit /* of 4096 characters. /* /* This is not an ESRI supported AML. Please use at your own risk. /* Also, please make a backup of your data before running this AML /* and carefully check the output. This is just a skeleton AML with /* no real error checking. It is meant only as a guide to developing an /* AML specific to your data inputs and desired outputs. /*Capture the comma delimited list of coverages from &RUN command ... &args covlist:REST
Use GENERATE with the LINE subcommand. Create a temporary coverage with the MBR arc using the min and max extents of all data.
Code: GENERATE tempcov LINE 1 <xmin> <ymin> <xmin> <ymax> <xmax> <ymax> <xmax> <ymin> <xmin> <ymin> END END QUIT
BUILD the temporary coverage for LINE. This will create the .AAT INFO file.
If any arcs of the DSnnnP coverage have a cover-ID of 1, they will conflict with the MBR arc's ID. You can avoid this by doing the following before using GET:
Code: CALC the DSnnnP-ID = DSnnnP-ID + 1
In ARCEDIT, make the temporary coverage the edit coverage with EDITFEATURE ARC and GET the DSnnnP coverage arcs. Save the edits and quit.
Store a backup of the DSnnnP coverage outside the workspace to be converted with ARCDFAD. Then COPY the temporary coverage to the ARCDFAD workspace, using the original DSnnnP name.
Note: DFAD 1-C data has extents that encompass 1 whole decimal degree. For example, a DFAD data set could have an extent such as:
xmin = 20 ymin = 30 xmax = 21 ymax = 31
However, the ARCDFAD converter does not check for such an extent. It will convert data even if it has an x and y extent that exceeds or is less than a full decimal degree. Appropriate data extents can be checked in the DFAD format specifications.