+/*
+ 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);
+
+bool categoricals_sane (const struct categoricals *cat);
+
+
+/*
+ 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);
+
+double categoricals_get_sum_by_subscript (const struct categoricals *cat, int subscript);
+
+/* 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);
+
+/* 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);
+
+
+/* These use the long map. Useful for descriptive statistics. */
+
+
+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 *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);