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10.3.1 Processing Summary

If you specify an output file on the command line, it stores the information that is displayed on the screen during processing. The file latlon.sum was specified as the output file in the example above.

Here is latlon.sum:

Input file : latlon.dat
Requested precision = 3, Approximate number of sorting bins = 100

Input data format       (latlon.fmt)
ASCII_input_data       "ASCII format"
The format contains 2 variables; length is 24.

Output data format       (latlon.fmt)
binary_output_data       "binary format"
The format contains 2 variables; length is 16.

Histogram data precision: 3, Number of sorting bins: 20
latitude: 20 values read
minimum: -83.223548 found at record  5
maximum:  77.883119 found at record 12
Summary file: latitude.lst

Histogram data precision: 3, Number of sorting bins: 20
longitude: 20 values read
minimum: -176.161101 found at record 1
maximum:  149.408117 found at record 4
Summary file: longitude.lst. 

The processing summary file latlon.sum first shows the name of the input data file (latlon.dat). If you specified precision and a maximum number of bins on the command line, those values are given as Requested precision, in this case 3, and Approximate number of sorting bins, in this case the default value of 100. If precision is not specified, No requested precision is shown.

A summary of each format shows the type of format (in this case, Input data format and Output data format) and the name of the format file containing the format descriptions (latlon.fmt), whether specified on the command line or located through the default search sequence (as detailed in chapter 4). In this case, it was located by default. Since checkvar only needs an input format description, it ignores output format descriptions. Next, you see the format descriptor as resolved by FreeForm ND (e.g., ASCII_input_data) and the format title (e.g., "ASCII format"). Then the number of variables in a record and total record length are given; for ASCII, record length includes the end-of-line character (1 byte for Unix).

A section for each variable processed by checkvar indicates the histogram precision and actual number of sorting bins. Under some circumstances, the precision of values in the histogram file may be different than the precision you specified on the command line. The default value for precision, if none is specified on the command line, is the precision specified in the relevant format description file or 5, whichever is smaller. The second line shows the name of the variable (latitude, longitude) and the number of values in the data file for the variable (20 for both latitude and longitude).

The minimum and maximum values for the variable are shown next (-83.223548 is the minimum and 77.883119 is the maximum value for latitude). The maximum and minimum values are given here with a precision of 6, which is the precision specified in the format description file. The locations of the maximum and minimum values in the input file are indicated. (-83.223548 is the fifth latitude value in latlon.dat and 77.883119 is the twelfth). Finally, the name of the histogram data (or variable summary) file generated for each variable is given (latitude.lst and longitude.lst).


Tom Sgouros and James Gallagher, 2006-02-12

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