Subsets are files storing sets of elements (the default extension of subset files is sub). Each element is stored as a four-byte element number. This way, subset file size in bytes is four times the number of elements in the subset. The same subset files can be used by different collections, but such use is meaningful only if the collections have the same numbering of elements (e.g. if these are copies of the same original collection)

Creating subsets

To create a subset use one of the following options:

• Subset : Save all on the browser pop-up menu - save the contents of the browser in a subset file (e.g. this option used on the browser opened with View : Memorized will create a subset with all memorized elements)
• Subset : Save selection on the browser pop-up menu - save all selected elements in the browser (selecting is done by clicking the leftmost column or with subset operations such as Add, Subtract and Intersect)
• Tools : Save as subset on the contents menu - save a contents branch in a subset file
• Child on the browser pop-up menu - create a sub-browser with all memorized, pending, dismissed or selected elements from the current browser. The new sub-browser can be used again in creating new subsets with Subset : Save all or Subset : Save selection (compare above)

Some subset files are created automatically for you. You can view them with View : Other browsers : Subset. For example: last_browser (subset with all elements displayed in the last opened browser), searched (subset with all elements found with the last Ctrl+F search), last_child (subset with elements extracted with the last Child operation in the browser), tasklist (subset will all tasks extracted with Tools : Open in browser on the tasklist manager menu), etc.

Note that subset operations in registries in conjunction with Browse current and Browse all are also useful here. For example: search for a given substring and choose Browse all (in the registry). You will create a browser with all elements using the founds texts. This browser can be saved in a subset file (Subset : Save all)

Using subsets

Subsets can be used in a number of ways. For example:

• View : Subset opens a given subset file in the browser
• Learn in the browser makes it possible to make repetitions on a subset of elements
• Ctrl+Alt+P in the browser postpones outstanding repetitions in a subset of elements
• Tools : Export Q&A text in the browser makes it possible to export a subset of elements as a text file of questions and answers
• browser sorting options help you review a subset of elements by increasing intervals, difficulty, memory lapses, etc.
• Tools : Random test : Subset - runs a random test on a subset of elements
• File : Tools : Export : Subset as text - exports a subset file as an element subset text file that can be imported to another collection
• File : Tools : Export : Translation - exports translation of texts used in elements from a subset file
• Tools : Match to subset on the registry pop-up menu - all registry members that are in use by elements listed in a subset file. For example, by using Search and replace : Find in a registry, one can easily find strings that are used by a given element subset and contain the selected search substring