Categoricals: Replace single value by a case, so that interactions can be supported

[pspp] / src / math / interaction.c

diff --git a/src/math/interaction.c b/src/math/interaction.c
index aa24250007da27b09723f5ddc4f115419fb10db5..afdc3277754884a69fe83b090c2c380321d55935 100644 (file)
--- a/src/math/interaction.c
+++ b/src/math/interaction.c
@@ -130,6 +130,25 @@ interaction_case_equal (const struct interaction *iact, const struct ccase *c1,
   return same;
 }
 
+
+int
+interaction_case_cmp_3way (const struct interaction *iact, const struct ccase *c1, const struct ccase *c2)
+{
+  int i;
+  int result = 0;
+
+  for (i = 0; i < iact->n_vars; ++i)
+    {
+      const struct variable *var = iact->vars[i];
+      result = value_compare_3way (case_data (c1, var), case_data (c2, var), var_get_width (var));
+      if (result != 0)
+       break;
+    }
+
+  return result;
+}
+
+
 bool
 interaction_case_is_missing (const struct interaction *iact, const struct ccase *c, enum mv_class exclude)
 {