Changes between Version 2 and Version 3 of DevNotes/Projects/categories

Timestamp:

Aug 28, 2012 11:04:40 AM (12 years ago)

Author:

kieranrcampbell

Comment:

—

DevNotes/Projects/categories

@@ -4 +4 @@
 Categories in Sansview is a new project to categorise the SANS models for easy selection from the GUI. In the fitpanel brought up are two listboxes - on containing relevant categories, the other containing the models belonging to the selected category. 
 
-Categories of a given model can be modified and the model shown/hidden from the UI using the Category Manager. This can be accessed via View -> CategoryManager. A model can also belong to multiple categories.
+Categories of a given model can be modified and the model shown/hidden from the UI using the Category Manager. This can be accessed via View => CategoryManager. A model can also belong to multiple categories.
 
 == Architecture ==
 
+Categories are stored in a dictionary that links categories to model names.
+The setup script was modified to scan the Sansview installation to find all
+installed models. The categorisation is stored in a python defaultdict linking
+each category name to a list of models. These are then serialized to file using
+the python library cPickle which provides fast data access and reading for a
+python data structure.
+
+There are three different data containers needed for smooth operator of the
+category model - master category dict, by model dict and model enabled dict.
+The first of these, master category dict is a defaultdict linking each cate-
+gory name (a string) to a python list of tuples, the first entry being the model
+name, and the second entry being whether the model has enabled or not by
+the user in the UI. Obviously the entire informational content of the category
+mechanism is stored here.
+
+The other two data structures exist to provide fast access in the opposite
+direction. Say, for example, we want to find all the categories a given model is
+in. We would need to trawl through the dictionary picking out all the (key, value)
+pairs corresponding to a particular model. Instead we use by model dict whose
+keys are the model name and whose values are lists of categories that contain
+a certain model. The same applies to finding whether a model is enabled. We
+have model enabed dict whose keys are model names and whose values are
+bools corresponding to whether the model should be shown in the GUI or not.
+
+Two methods exist to generate the structures from each other. regenerate master dict
+will create master category dict from by model dict and model enabled dict.
+regenerate model dict will create by model dict and model enabled dict
+from master category dict. These methods are implemented in different places
+depending on the exact usage. A good place to start is with the methods
+and docs in CategoryManager. They’re also implemented in basepage.py and
+CategoryInstaller.
+
+
 == Other Documents ==