union value ;
-struct categoricals *categoricals_create (struct interaction *const *, size_t n_int,
- const struct variable *wv, enum mv_class dep_excl,
- enum mv_class fctr_excl);
+/* Categoricals.
+
+ A categorical variable has a finite and usually small number of possible
+ values. The categoricals data structure organizes an array of interactions
+ maong categorical variables, that is, a set of sets of categorical
+ variables. (Both levels of "set" are ordered.)
+
+ The life cycle of a categoricals object looks like this:
+
+ 1. Create it with categoricals_create(). This fixes the set of interactions
+ and other parameters.
+
+ 2. Pass all of the desired cases through the object with
+ categoricals_update().
+
+ 3. Finalize the object with categoricals_done(). Only at this point may
+ most of the categoricals query functions be called.
+
+ 4. Use the categoricals object as desired.
+
+ 5. Destroy the object with categoricals_destroy().
+*/
+/* Creating and destroying categoricals. */
+struct categoricals *categoricals_create (struct interaction *const*, size_t n_int,
+ const struct variable *wv,
+ enum mv_class fctr_excl);
void categoricals_destroy (struct categoricals *);
+/* Updating categoricals. */
void categoricals_update (struct categoricals *cat, const struct ccase *c);
+void categoricals_done (const struct categoricals *cat);
+bool categoricals_is_complete (const struct categoricals *cat);
+
+/* Counting categories.
+
+ A variable's number of categories is the number of unique values observed in
+ the data passed to categoricals_update().
+ An interaction's number of categories is the number of observed unique
+ values of its variables, which will often be less than the product of its
+ variables' numbers of categories.
+ A categorical object's number of categories is the sum of its interactions'
+ categories. */
/* Return the number of categories (distinct values) for variable N */
size_t categoricals_n_count (const struct categoricals *cat, size_t n);
+size_t categoricals_n_total (const struct categoricals *cat);
-size_t categoricals_df (const struct categoricals *cat, size_t n);
+/* Degrees of freedom.
-/* Return the total number of categories */
-size_t categoricals_n_total (const struct categoricals *cat);
+ A categorical variable with N_CATS categories has N_CATS - 1 degrees of
+ freedom.
-/* Return the total degrees of freedom */
-size_t categoricals_df_total (const struct categoricals *cat);
+ An interaction's degrees of freedom is the product of its variables' degrees
+ of freedom.
+ A categorical object's degrees of freedom is the sum of its interactions'
+ degrees of freedom. */
+size_t categoricals_df (const struct categoricals *cat, size_t n);
+size_t categoricals_df_total (const struct categoricals *cat);
-/*
- Return the total number of variables which participated in these categoricals.
- Due to the possibility of missing values, this is NOT necessarily
- equal to the number of variables passed in when the object was
- created.
-*/
size_t categoricals_get_n_variables (const struct categoricals *cat);
-bool categoricals_is_complete (const struct categoricals *cat);
-
+/* Sanity. */
+bool categoricals_sane (const struct categoricals *cat);
-/*
- Must be called (once) before any call to the *_by_subscript or *_by_category
- functions, but AFTER any calls to categoricals_update.
- If this function returns false, then no calls to _by_subscript or *_by_category
- are allowed.
-*/
-void categoricals_done (const struct categoricals *cat);
+/* "Short map".
-bool categoricals_sane (const struct categoricals *cat);
+ These look up an interaction within a categoricals object on the basis of a
+ "subscript". Interaction 0 with DF_0 degrees of freedom is assigned
+ subscripts [0, DF_0 - 1], interaction 1 with DF_1 degrees of freedom is
+ assigned subscripts [DF_0, DF_0 + DF_1 - 1], and so on. The subscripts
+ passed in must be in the range [0, DF_SUM - 1] where DF_SUM is the total
+ number of degrees of freedom for the object, as returned by
+ categoricals_df_total().
+ These functions are intended for covariance matrix routines, where normally
+ 1 less than the total number of distinct values of each categorical variable
+ should be considered.
-/*
- The *_by_subscript functions use the short map.
- Their intended use is by covariance matrix routines, where normally 1 less than
- the total number of distinct values of each categorical variable should
- be considered.
- */
+ These functions may be used on an object only after calling
+ categoricals_done().
+*/
double categoricals_get_weight_by_subscript (const struct categoricals *cat, int subscript);
const struct interaction *categoricals_get_interaction_by_subscript (const struct categoricals *cat, int subscript);
double categoricals_get_sum_by_subscript (const struct categoricals *cat, int subscript);
+double
+categoricals_get_dummy_code_for_case (const struct categoricals *cat, int subscript,
+ const struct ccase *c);
+double
+categoricals_get_effects_code_for_case (const struct categoricals *cat, int subscript,
+ const struct ccase *c);
-double categoricals_get_code_for_case (const struct categoricals *cat, int subscript, const struct ccase *c);
+/* "Long map".
-/* These use the long map. Useful for descriptive statistics. */
+ These look up an interaction within a categoricals object on the basis of a
+ "category index". Interaction 0 in CAT with CAT_0 categories has indexes
+ [0, CAT_0 - 1], interaction 1 with CAT_1 categories has indexes [CAT_0,
+ CAT_0 + CAT_1 - 1], and so on. The indexes passed in must be in the range
+ [0, CAT_TOTAL - 1] where CAT_TOTAL is the total number of categories for the
+ object, as returned by categoricals_n_total().
-/* Return the value corresponding to the N'th category */
-const union value * categoricals_get_value_by_category (const struct categoricals *cat, int n);
+ These functions are useful for descriptive statistics.
+ These functions may be used on an object only after calling
+ categoricals_done().
+*/
const struct ccase *
categoricals_get_case_by_category_real (const struct categoricals *cat, int iact, int n);
-
void *
categoricals_get_user_data_by_category_real (const struct categoricals *cat, int iact, int n);
-
-
void * categoricals_get_user_data_by_category (const struct categoricals *cat, int category);
-
const struct ccase * categoricals_get_case_by_category (const struct categoricals *cat, int subscript);
-
struct payload
{
void* (*create) (const void *aux1, void *aux2);
void (*update) (const void *aux1, void *aux2, void *user_data, const struct ccase *, double weight);
void (*calculate) (const void *aux1, void *aux2, void *user_data);
- void (*destroy) (const void *aux1, void *user_data);
+ void (*destroy) (const void *aux1, void *aux2, void *user_data);
};
-
void categoricals_set_payload (struct categoricals *cats, const struct payload *p, const void *aux1, void *aux2);
+bool categoricals_isbalanced (const struct categoricals *cat);
#endif