#ifndef INTERACTION_H
#define INTERACTION_H
+#include <data/case.h>
+
struct interaction_variable;
struct interaction_value;
struct interaction_value * interaction_value_create (const struct interaction_variable *, const union value **);
void interaction_value_destroy (struct interaction_value *);
size_t interaction_variable_get_n_vars (const struct interaction_variable *);
-
+double interaction_value_get_nonzero_entry (const struct interaction_value *);
+const union value *interaction_value_get (const struct interaction_value *);
+const struct variable * interaction_get_variable (const struct interaction_variable *);
+size_t interaction_get_n_numeric (const struct interaction_variable *);
+size_t interaction_get_n_alpha (const struct interaction_variable *);
+size_t interaction_get_n_vars (const struct interaction_variable *);
+const struct variable * interaction_get_member (const struct interaction_variable *, size_t);
+bool is_interaction (const struct variable *, const struct interaction_variable **, size_t);
+struct interaction_value *
+interaction_case_data (const struct ccase *, const struct interaction_variable *);
+double interaction_value_get_nonzero_entry (const struct interaction_value *);
#endif