casereader_create_filter_missing (struct casereader *,
const struct variable **vars, size_t var_cnt,
enum mv_class,
+ casenumber *n_missing,
struct casewriter *exclude);
struct casereader *
bool (*destroy) (void *aux),
void *aux);
+/* A function which creates a numberic value from an existing case */
+typedef double new_value_func (const struct ccase *, casenumber, void *);
+
+struct casereader *
+casereader_create_append_numeric (struct casereader *subreader,
+ new_value_func func, void *aux,
+ void (*destroy) (void *aux));
+
struct casereader *
casereader_create_arithmetic_sequence (struct casereader *,
double first, double increment);