X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fmath%2Fcategoricals.h;h=d5a8b0df9519b2fbf5f2911a7704bb6a40a6c486;hb=f0168bf82cd65cb3af7f0816dc64af06dc17636d;hp=28e0f5f1df98fc422d2fbae13296c4003f794cdf;hpb=3e81b17836ef4f026b2321a6a79418c7f0cb9121;p=pspp diff --git a/src/math/categoricals.h b/src/math/categoricals.h index 28e0f5f1df..d5a8b0df95 100644 --- a/src/math/categoricals.h +++ b/src/math/categoricals.h @@ -28,89 +28,133 @@ struct interaction; 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 *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