Logistic Regression: Added categorical variable support

[pspp] / src / math / categoricals.c

diff --git a/src/math/categoricals.c b/src/math/categoricals.c
index 71ffe20ad7ee66ec646f1684bd524e44f5c043ca..d0247f6d38a453cbbf7220e04f11f879a5140d65 100644 (file)
--- a/src/math/categoricals.c
+++ b/src/math/categoricals.c
@@ -76,15 +76,6 @@ struct variable_node
 
   struct hmap valmap;         /* A map of value nodes */
   int n_vals;                 /* Number of values for this variable */
-
-  int *indirection;           /* An array (of size n_vals) of integers, which serve to
-                                permute the index members of the values in valmap.
-                                
-                                Doing this, means that categories are considered in the order
-                                of their values.  Mathematically the order is irrelevant.
-                                However certain procedures (eg logistic regression)  want to report
-                                statisitics for particular categories */
-
 };
 
 
@@ -412,7 +403,8 @@ categoricals_update (struct categoricals *cat, const struct ccase *c)
       if (valn == NULL)
        {
          valn = pool_malloc (cat->pool, sizeof *valn);
-         valn->index = vn->n_vals++;
+         valn->index = -1; 
+         vn->n_vals++;
          value_init (&valn->val, width);
          value_copy (&valn->val, val, width);
          hmap_insert (&vn->valmap, &valn->node, hash);
@@ -553,15 +545,14 @@ categoricals_done (const struct categoricals *cat_)
              return;
            }
 
-         vn->indirection = pool_calloc (cat->pool, vn->n_vals, sizeof *vn->indirection);
-
          /* Sort the VALMAP here */
          array = xcalloc (sizeof *array, vn->n_vals);
+         x = 0;
          HMAP_FOR_EACH (valnd, struct value_node, node, &vn->valmap)
            {
              /* Note: This loop is probably superfluous, it could be done in the 
               update stage (at the expense of a realloc) */
-             array[valnd->index] = valnd;
+             array[x++] = valnd;
            }
 
          sort (array, vn->n_vals, sizeof (*array), 
@@ -570,7 +561,7 @@ categoricals_done (const struct categoricals *cat_)
          for (x = 0; x <  vn->n_vals; ++x)
            {
              struct value_node *vvv = array[x];
-             vn->indirection[vn->n_vals - x - 1] = vvv->index;
+             vvv->index = x;
            }
          free (array);
 
@@ -753,9 +744,9 @@ categoricals_get_code_for_case (const struct categoricals *cat, int subscript,
       const int index = ((subscript - base_index) % iap->df_prod[v] ) / dfp;
       dfp = iap->df_prod [v];
 
-      if (effects_coding && vn->indirection [valn->index] == df )
+      if (effects_coding && valn->index == df )
        bin = -1.0;
-      else if ( vn->indirection [valn->index] != index )
+      else if ( valn->index != index )
        bin = 0;
     
       result *= bin;