Take, for instance, the camera make/model category that ships with IMatch: The sorting seems to be alphabetically. Is it at all possible to say, for instance, configure the Level 1 "Make" category so that the camera brands that have the highest population would be output at the top, and then the brands with the lowest numbers, be at the bottom?
You cannot sort individual segments of your category hierarchy. The category hierarchy is sorted by the global category sort order you can control via the gear icon in the Category View toolbar.
The standard sort sequence sorts alphabetically, sensitive to numerical values. Which means that your make is sorted by name, but e.g. ISO is stored ascending by the numerical value. It depends on how you choose the data type for your DD category. All this is explained in the help for the data-driven categories.
For statistics and analysis, please use the statistics panel or the Data Mapper app.
Both features allow you to analyze your files by criteria like "Show my the distribution of my files by make".
(https://www.photools.com/community/index.php?action=dlattach;topic=5706.0;attach=12853;image)
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