#include "data/missing-values.h"
struct categoricals;
-struct variable;
struct ccase;
struct interaction;
+struct variable;
+union value;
-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);
-
-void categoricals_destroy (struct categoricals *);
-
-void categoricals_update (struct categoricals *cat, const struct ccase *c);
+/* 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.)
-/* Return the number of categories (distinct values) for variable N */
-size_t categoricals_n_count (const struct categoricals *cat, size_t n);
+ The life cycle of a categoricals object looks like this:
-size_t categoricals_df (const struct categoricals *cat, size_t n);
+ 1. Create it with categoricals_create(). This fixes the set of interactions
+ and other parameters.
-/* Return the total number of categories */
-size_t categoricals_n_total (const struct categoricals *cat);
+ 2. Pass all of the desired cases through the object with
+ categoricals_update().
-/* Return the total degrees of freedom */
-size_t categoricals_df_total (const struct categoricals *cat);
+ 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.
-/*
- 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.
+ 5. Destroy the object with categoricals_destroy().
*/
-size_t categoricals_get_n_variables (const struct categoricals *cat);
-bool categoricals_is_complete (const struct categoricals *cat);
+/* Creating and destroying categoricals. */
+struct categoricals *categoricals_create (struct interaction *const *,
+ size_t n,
+ const struct variable *wv,
+ enum mv_class fctr_excl);
+void categoricals_destroy (struct categoricals *);
+/* Updating categoricals. */
+void categoricals_update (struct categoricals *, const struct ccase *);
+void categoricals_done (const struct categoricals *);
+bool categoricals_is_complete (const struct categoricals *);
-/*
- 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);
+/* Categories.
-bool categoricals_sane (const struct categoricals *cat);
+ 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.
-/*
- 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.
- */
-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);
+ A categorical object's number of categories is the sum of its interactions'
+ categories. */
+size_t categoricals_n_count (const struct categoricals *, size_t idx);
+size_t categoricals_n_total (const struct categoricals *);
-double categoricals_get_sum_by_subscript (const struct categoricals *cat, int subscript);
+union value *categoricals_get_var_values (const struct categoricals *,
+ const struct variable *, size_t *n);
-/* Returns unity if the value in case C at SUBSCRIPT is equal to the category
- for that subscript */
-double
-categoricals_get_dummy_code_for_case (const struct categoricals *cat, int subscript,
- const struct ccase *c);
+/* Degrees of freedom.
-/* Returns unity if the value in case C at SUBSCRIPT is equal to the category
- for that subscript.
- Else if it is the last category, return -1.
- Otherwise return 0.
- */
-double
-categoricals_get_effects_code_for_case (const struct categoricals *cat, int subscript,
- const struct ccase *c);
+ A categorical variable with N_CATS categories has N_CATS - 1 degrees of
+ freedom.
+ An interaction's degrees of freedom is the product of its variables' degrees
+ of freedom.
-/* These use the long map. Useful for descriptive statistics. */
+ A categorical object's degrees of freedom is the sum of its interactions'
+ degrees of freedom. */
+size_t categoricals_df (const struct categoricals *, size_t idx);
+size_t categoricals_df_total (const struct categoricals *);
+/* Sanity. */
+bool categoricals_sane (const struct categoricals *cat);
-const struct ccase *
-categoricals_get_case_by_category_real (const struct categoricals *cat, int iact, int n);
+/* "Short map".
-void *
-categoricals_get_user_data_by_category_real (const struct categoricals *cat, int iact, int n);
+ 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.
-void * categoricals_get_user_data_by_category (const struct categoricals *cat, int category);
+ These functions may be used on an object only after calling
+ categoricals_done().
+*/
+double categoricals_get_weight_by_subscript (const struct categoricals *,
+ int subscript);
+const struct interaction *categoricals_get_interaction_by_subscript (
+ const struct categoricals *, int subscript);
+double categoricals_get_sum_by_subscript (const struct categoricals *,
+ int subscript);
+double categoricals_get_dummy_code_for_case (const struct categoricals *,
+ int subscript,
+ const struct ccase *);
+double categoricals_get_effects_code_for_case (const struct categoricals *,
+ int subscript,
+ const struct ccase *);
+
+
+/* "Long map".
+
+ 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().
+
+ 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 *, int iact, int n);
+void *categoricals_get_user_data_by_category_real (
+ const struct categoricals *, int iact, int n);
-const struct ccase * categoricals_get_case_by_category (const struct categoricals *cat, int subscript);
+int categoricals_get_value_index_by_category_real (
+ const struct categoricals *, int iact_idx, int cat_idx, int var_idx);
+void *categoricals_get_user_data_by_category (const struct categoricals *,
+ 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 *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);
+ {
+ 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 *aux2, void *user_data);
+ };
+
+void categoricals_set_payload (struct categoricals *, const struct payload *,
+ const void *aux1, void *aux2);
+bool categoricals_isbalanced (const struct categoricals *);
#endif