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9.5.2 "Nonstandard" Format Description File Names

If you are using a format description file that does not follow FreeForm ND file naming conventions, you must include its name on the command line. Assume that you want to convert the ASCII data file latlon.dat to the binary file latlon.bin, and the input and output data formats are both described in llvals.frm (not included in the example file set). The data file names follow FreeForm ND conventions, but the name of the format description file does not, so it will not be located through the default search sequence. Use the following command to convert to binary:

newform latlon.dat -f llvals.frm -o latlon.bin 

Suppose now that the input format is described in latlon.fmt and the output format in llvals.frm. You do not need to explicitly specify the input format description file because it will be located by default, but you must specify the output format description file name. In this case, the command would be:

newform latlon.dat -of llvals.frm -o latlon.bin 

You can always unambiguously specify the names of format description files and data files, whether or not their names follow FreeForm ND conventions. Assume you want to look only at longitude values in latlon.bin and that you want them defined as integers (longs) which are right-justified at column 30. You will reformat the specified binary data in latlon.bin into ASCII data in longonly.dat and then view it. The input format is found in latlon.fmt, the output format in longonly.fmt.

Here is longonly.fmt:

/ This is the format description file for viewing longitude as an 
/ integer value right-justified at column 30.

ASCII_data "ASCII output format, right-justified at 30"
longitude 20 30 long 6

In this case, you have decided to look at the first 5 longitude values. Use the following command to unambiguously designate all files involved:

newform latlon.bin -if latlon.fmt -of longonly.fmt -c 5 
       -o longonly.dat

When you view longonly.dat, you should see the following 5 values:

         1         2         3         4
1234567890123456789012345678901234567890

                    -176161101
                        777265
                      35591879
                     149408117
                      55319598

Tom Sgouros and James Gallagher, 2006-02-12

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