Implement MRSETS command.

[pspp] / src / data / mrset.c

diff --git a/src/data/mrset.c b/src/data/mrset.c
new file mode 100644 (file)
index 0000000..2f05edb
--- /dev/null
+++ b/src/data/mrset.c
@@ -0,0 +1,104 @@
+/* PSPP - a program for statistical analysis.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include "data/mrset.h"
+
+#include <stdlib.h>
+
+#include "data/dictionary.h"
+#include "data/val-type.h"
+#include "data/variable.h"
+
+#include "gl/xalloc.h"
+
+/* Creates and returns a clone of OLD.  The caller is responsible for freeing
+   the new multiple response set (using mrset_destroy()). */
+struct mrset *
+mrset_clone (const struct mrset *old)
+{
+  struct mrset *new;
+
+  new = xmalloc (sizeof *new);
+  new->name = xstrdup (old->name);
+  new->label = old->label != NULL ? xstrdup (old->label) : NULL;
+  new->type = old->type;
+  new->vars = xmemdup (old->vars, old->n_vars * sizeof *old->vars);
+  new->n_vars = old->n_vars;
+
+  new->cat_source = old->cat_source;
+  new->label_from_var_label = old->label_from_var_label;
+  value_clone (&new->counted, &old->counted, old->width);
+  new->width = old->width;
+
+  return new;
+}
+
+/* Frees MRSET and the data that it contains. */
+void
+mrset_destroy (struct mrset *mrset)
+{
+  if (mrset != NULL)
+    {
+      free (mrset->name);
+      free (mrset->label);
+      free (mrset->vars);
+      value_destroy (&mrset->counted, mrset->width);
+    }
+}
+
+/* Checks various constraints on MRSET:
+
+   - MRSET has a valid name for a multiple response set (beginning with '$').
+
+   - MRSET has a valid type.
+
+   - MRSET has at least 2 variables.
+
+   - All of MRSET's variables are in DICT.
+
+   - All of MRSET's variables are the same type (numeric or string).
+
+   - If MRSET is a multiple dichotomy set, its counted value has the same type
+     as and is no wider than its narrowest variable.
+
+   Returns true if all the constraints are satisfied, otherwise false. */
+bool
+mrset_ok (const struct mrset *mrset, const struct dictionary *dict)
+{
+  enum val_type type;
+  size_t i;
+
+  if (mrset->name == NULL
+      || mrset->name[0] != '$'
+      || (mrset->type != MRSET_MD && mrset->type != MRSET_MC)
+      || mrset->vars == NULL
+      || mrset->n_vars < 2)
+    return false;
+
+  type = var_get_type (mrset->vars[0]);
+  if (mrset->type == MRSET_MD && type != val_type_from_width (mrset->width))
+    return false;
+  for (i = 0; i < mrset->n_vars; i++)
+    if (!dict_contains_var (dict, mrset->vars[i])
+        || type != var_get_type (mrset->vars[i])
+        || (mrset->type == MRSET_MD
+            && mrset->width > var_get_width (mrset->vars[i])))
+      return false;
+
+  return true;
+}