Appendix H HPMS Field Manual
December 2000
APPENDIX H
LRS Data File Template Procedures
The data required for the Linear Referencing System (LRS) templates are described in Chapter V. This chapter provides assistance to the user for entering the Node Data File and the Inventory Route Link Data File in dBase III or IV. This information can also be provided as an ASCII file on floppy disk, CD, or as an electronic file. For a more complete discussion of the data transfer media and necessary documentation, please see Chapter V.
The following discussion assumes the user is familiar with dBase and that the appropriate version of dBase is available. A dBase template is provided for both the Node Data File and the Inventory Route Link Data File information listed in Chapter V. These are named NODE.DBF and LINK.DBF, which must be added to one of the user’s dBase catalogs. This is accomplished by copying these files into the dBase working directory. At the dBase dot prompt, type:
.USE <NODE or LINK>
Where NODE and LINK are the NODE.DBF and LINK.DBF files described above.
OPTION 1: Manual Data Entry, Abbreviated Field Names
Once the “USE” command has been executed for either the NODE or LINK files, the user can begin to enter data for that file. This is done by using the “APPEND” command:
.APPEND
The template will appear in the upper left corner of the computer screen and is ready for data entry.
Add data to the file by typing in the appropriate codes or values.
Single records are presented on the screen with fields placed in a vertical structure for each record in the same order as shown in Chapter V (i.e., Year is above State Code, which is above County Code, etc.).
The cursor will move from one field to the next as data is entered (when the “Enter/Return” key is depressed). dBase will not allow the user to enter character data into a numeric field.
Once a record is complete (when “Enter/Return” is depressed at the last data item), a new record will appear. This will continue until the operator discontinues the data entry process and saves the data file.
OPTION 2: Manual Data Entry, Full Name Fields
As an option, a special template has been provided that contains a more complete description of the various data item fields (i.e., the description of the data fields are the same as those shown in Chapter V). These templates come from the NODE.FMT and LINK.FMT files. If the user wishes to use these special templates, the “.FMT” files must be copied into the same directory as the “.DBF” files discussed earlier. To use this template, execute the “SET FORMAT” command:
.USE <NODE or LINK>
.SET FORMAT TO <NODE or LINK>
.APPEND
The file selected with the “USE” command (either the NODE or LINK “.DBF” files) must also be selected with the “SET FORMAT” command (NODE or LINK “.FMT” files). When the “APPEND” command is executed, the special template will appear.
Data entry, as well as the order of the data fields, is the same as in Option 1.
OPTION 3: Automatic Computer Data Entry
If the data can be obtained from the State’s database and be placed into an ASCII format, the file can be imported into dBase. The user can import the ASCII file into dBase with the following steps. Copy the NODE.DBF, LINK.DBF, and the ASCII files into the dBase working directory, and execute the following commands:
.USE <NODE or LINK>
.APPEND FROM <YourAsciiFile> TYPE <SDF>
The file (either NODE or LINK) that the user selects with the “USE” command must be appended with the corresponding Node or Link ASCII file. When preparing the ASCII file, the State must ensure that the field positions and lengths match those of the appropriate Node Data File and Inventory Route Link Data File in Chapter V. The ASCII file type used in this example is fixed length (shown in the above “APPEND” command as <SDF>), but dBase can accept other types of delimited ASCII files (check the dBase manual for appropriate ASCII type).
OPTION 4: ASCII File
This option does not use dBase. If the data can be obtained from the State’s PC database and placed into an ASCII format, the file can be directly submitted to FHWA in that fashion. When preparing the ASCII file, the State must ensure that the field lengths and positions match those of the appropriate Node Data File and Inventory Route Link Data File in Chapter V. The ASCII file type should be fixed length, but if different, the file type should be fully explained in the correspondence.
OPTION 5: EBCDIC File
This option does not use dBase. If the data can be obtained from the State’s mainframe database and placed into an EBCDIC format, the mainframe file may be downloaded to a PC and submitted to FHWA as an ASCII file.
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File Type | application/msword |
File Modified | 0000-00-00 |
File Created | 0000-00-00 |