sort: New function sort_distinct_execute().

[pspp] / src / math / sort.c

diff --git a/src/math/sort.c b/src/math/sort.c
index 61256ccdbc6d1f8dd19e284232778263a585ed41..752d5270007bcdc4d505e2eb4ad4ba887b27e8fd 100644 (file)
--- a/src/math/sort.c
+++ b/src/math/sort.c
@@ -219,6 +219,23 @@ sort_execute_1var (struct casereader *input, const struct variable *var)
   subcase_destroy (&sc);
   return reader;
 }
+
+/* Reads all the cases from INPUT.  Sorts the cases according to ORDERING,
+   combining cases that have the same ORDERING values using COMBINE.
+   Returns the sorted cases in a new casereader. */
+struct casereader *
+sort_distinct_execute (struct casereader *input,
+                       const struct subcase *ordering,
+                       sort_distinct_combine_func *combine,
+                       sort_distinct_destroy_func *destroy,
+                       void *aux)
+{
+  struct casewriter *output =
+    sort_distinct_create_writer (ordering, casereader_get_proto (input),
+                                 combine, destroy, aux);
+  casereader_transfer (input, output);
+  return casewriter_make_reader (output);
+}
 \f
 struct pqueue
   {