Options Dialog Box: Comparison

You use the Comparison page of the Options dialog box to set comparison options for files and lines in files.

After you set comparison options, you must rescan the files you are comparing, for the options to take effect.

File Comparison

To set file comparison options:

1. Choose Options > Options.
   The Options dialog box appears.
2. In the Options box, click Comparison.
3. Use the check boxes under Ignore blanks to define which blanks Compare It! should ignore during comparison:
   
   

   Select ...	To ignore blanks ...
   all	all spaces
   leading	at line start
   trailing	at line end
   not-word	between letter and not-letter
   multiple	change in number of spaces

4. To ignore special escape characters, like Form Feed (0x0C), set the Ignore special characters option.
5. To ignore added empty lines during comparison, select the Ignore inserted empty lines check box.
6. To ignore wrapped lines, select the Ignore line wraps check box.
7. To ignore case during comparison, select the Ignore case check box.
8. If you define a value (N) in the Min string length to match field, the same lines of length below N will not break a block of changed lines.
   This can be useful for programmers, otherwise just set it 0.
9. If you want to use regular expressions to ignore parts of lines in files, select the Use Regular Expressions check box.
   The Regular expressions dialog box appears. Use this dialog box to add and remove regular expressions.
10. To specify line columns to compare (for example, ignore first 5 characters), select the Use columns range check box and enter a number in the field.
    See Defining Column Ranges for details.
11. To toggle moved sections detection, use Find moved section check box.
    See Moved sections discussion for details.
12. To automatically use partial matching engine in whole file, set Force partial matching check box.
    See Partial matching for an explanations.

Line Comparison

Exact comparison can be more confusing than useful. Here is an example:

This is sample string
And here is another one

These lines are completely different, but the comparison shows you some of the same symbols. You can use two options for line comparison to avoid this kind of result.

To set line comparison options:

1. Choose Options > Options.
   The Options dialog box appears.
2. In the Options box, click Comparison.
3. To automatically use line comparison, select the Use line comparison check box.
4. Use the Min chars to match field to set the minimal number of matching characters in sequence to use during the comparison.
5. Use the Min % of line to match field to switch off comparison of very different lines if the total count of identical fragments is less than the specified percentage.
   In the example above, the sample lines have lengths of (21 + 23) = 44 symbols, and the total length of matched fragments is (5 * 2) = 10, and there is only about 23% match.
6. With Use adaptive comparison checkbox you can toggle usage of Adaptive line comparison algorithm.

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