X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fmath%2Finteraction.c;h=a36755b541265fbc3da3e1ca8fcc465ec0ea120e;hb=b20b80bfeb88eca603cb5c10b5a7188387fd23fd;hp=2d670b2dc726ff98656dd9fbd967a9bfd96d04d3;hpb=97a777315ec2f2000ac67da1f405323a5e2294e2;p=pspp

diff --git a/src/math/interaction.c b/src/math/interaction.c
index 2d670b2dc7..a36755b541 100644
--- a/src/math/interaction.c
+++ b/src/math/interaction.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+   Copyright (C) 2011, 2012 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
@@ -14,89 +14,235 @@
    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/case.h"
+#include "interaction.h"
+
+#include "data/value.h"
+#include "data/variable.h"
+#include "libpspp/str.h"
+
+#include "gl/xalloc.h"
+
+#include <stdio.h>
+
+
 /*
-  An interaction is a gsl_vector containing a "product" of other
-  variables. The variables can be either categorical or numeric.
-  If the variables are all numeric, the interaction is just the
-  scalar product. If any of the variables are categorical, their
-  product is a vector containing 0's in all but one entry. This entry
-  is found by combining the vectors corresponding to the variables'
-  OBS_VALS member. If there are K categorical variables, each with
-  N_1, N_2, ..., N_K categories, then the interaction will have
-  N_1 * N_2 * N_3 *...* N_K - 1 entries.
+  An interaction is a structure containing a "product" of other
+  variables. The variables can be either string or numeric.
+
+  Interaction is commutative.  That means, that from a mathematical point of
+  view,  the order of the variables is irrelevant.  However, for display
+  purposes, and for matching with an interaction's value the order is 
+  pertinent.
+  
+  Therefore, when using these functions, make sure the orders of variables 
+  and values match when appropriate.
+*/
+
+
+struct interaction *
+interaction_create (const struct variable *v)
+{
+  struct interaction  *i = xmalloc (sizeof *i);
+  i->vars = xmalloc (sizeof *i->vars);
+  i->n_vars = 0;
+  if ( v )
+    {
+      i->vars[0] = v;
+      i->n_vars = 1;
+    }
+  return i;
+}
+
+/* Deep copy an interaction */
+struct interaction *
+interaction_clone (const struct interaction *iact)
+{
+  int v;
+  struct interaction  *i = xmalloc (sizeof *i);
+  i->vars = xcalloc (iact->n_vars, sizeof *i->vars);
+  i->n_vars = iact->n_vars;
+
+  for (v = 0; v < iact->n_vars; ++v)
+    {
+      i->vars[v] = iact->vars[v];
+    }
+
+  return i;
+}
+
+
+void
+interaction_destroy (struct interaction *i)
+{
+  if (NULL == i)
+    return;
+
+  free (i->vars);
+  free (i);
+}
+
+void
+interaction_add_variable (struct interaction *i, const struct variable *v)
+{
+  i->vars = xrealloc (i->vars, sizeof (*i->vars) * ++i->n_vars);
+  i->vars[i->n_vars - 1] = v;
+}
+
+
+/*
+  Do the variables in X->VARS constitute a proper
+  subset of the variables in Y->VARS?
  */
+bool
+interaction_is_proper_subset (const struct interaction *x, const struct interaction *y)
+{
+  if (x->n_vars >= y->n_vars)
+    return false;
 
-#include <config.h>
-#include <assert.h>
-#include <libpspp/alloc.h>
-#include <gsl/gsl_math.h>
-#include <gsl/gsl_vector.h>
-#include <data/category.h>
-#include <data/variable.h>
-#include "interaction.h"
+  return interaction_is_subset (x, y);
+}
 
 /*
-  Convert a list of values to a binary vector. The order of VALS must
-  correspond to the order of V.
+  Do the variables in X->VARS constitute a 
+  subset (proper or otherwise) of the variables in Y->VARS?
  */
-gsl_vector *
-get_interaction (union value **vals, const struct variable **v, size_t n_vars)
+bool
+interaction_is_subset (const struct interaction *x, const struct interaction *y)
 {
-  gsl_vector *result = NULL;
-  size_t *subs = NULL;
-  size_t length = 1;
   size_t i;
   size_t j;
-  double tmp = 1.0;
+  size_t n = 0;
 
-  assert (n_vars > 0);
-  for (i = 0; i < n_vars; i++)
+  /* By definition, a subset cannot have more members than its superset */
+  if (x->n_vars > y->n_vars)
+    return false;
+
+  /* Count the number of values which are members of both sets */
+  for (i = 0; i < x->n_vars; i++)
     {
-      if (var_is_alpha (v[i]))
+      for (j = 0; j < y->n_vars; j++)
 	{
-	  length *= cat_get_n_categories (v[i]);
-	}
-      else
-	{
-	  length = (length > 0) ? length : 1;
+	  if (x->vars [i] == y->vars [j])
+	    {
+	      n++;
+	    }
 	}
     }
-  if (length > 0)
+
+  /* If ALL the members of X were also found in Y, then this must be a subset */    
+  if (n >= x->n_vars)
+    return true;
+
+  return false;
+}
+
+
+
+
+void
+interaction_dump (const struct interaction *i)
+{
+  int v = 0;
+  if ( i->n_vars == 0)
     {
-      length--;
+      printf ("(empty)\n");
+      return;
     }
+  printf ("%s", var_get_name (i->vars[v]));
+  for (v = 1; v < i->n_vars; ++v)
+    printf (" * %s", var_get_name (i->vars[v]));
+  printf ("\n");
+}
 
-  result = gsl_vector_calloc (length);
-  subs = xnmalloc (n_vars, sizeof (*subs));
-  for (j = 0; j < n_vars; j++)
+/* Appends STR with a representation of the interaction, suitable for user
+   display.
+
+   STR must have been initialised prior to calling this function.
+*/
+void
+interaction_to_string (const struct interaction *iact, struct string *str)
+{
+  int v = 0;
+  if ( iact->n_vars == 0)
+    return;
+  ds_put_cstr (str, var_to_string (iact->vars[v]));
+  for (v = 1; v < iact->n_vars; ++v)
     {
-      if (var_is_alpha (v[j]))
-	{
-	  subs[j] = cat_value_find (v[j], vals[j]);
-	}
+      ds_put_cstr (str, " * ");
+      ds_put_cstr (str, var_to_string (iact->vars[v]));
     }
-  j = subs[0];
-  for (i = 1; i < n_vars; i++)
+}
+
+unsigned int
+interaction_case_hash (const struct interaction *iact, const struct ccase *c, unsigned int base)
+{
+  int i;
+  size_t hash = base;
+  for (i = 0; i < iact->n_vars; ++i)
     {
-      j = j * cat_get_n_categories (v[i]) + subs[i];
+      const struct variable *var = iact->vars[i];
+      const union value *val = case_data (c, var);
+      hash = value_hash (val, var_get_width (var), hash);
     }
-  gsl_vector_set (result, j, 1.0);
-  /*
-     If any of the variables are numeric, the interaction of that
-     variable with another is just a scalar product.
-   */
-  for (i = 1; i < n_vars; i++)
+  return hash;
+}
+
+bool
+interaction_case_equal (const struct interaction *iact, const struct ccase *c1, const struct ccase *c2)
+{
+  int i;
+  bool same = true;
+
+  for (i = 0; i < iact->n_vars; ++i)
     {
-      if (var_is_numeric (v[i]))
+      const struct variable *var = iact->vars[i];
+      if ( ! value_equal (case_data (c1, var), case_data (c2, var), var_get_width (var)))
 	{
-	  tmp *= vals[i]->f;
+	  same = false;
+	  break;
 	}
     }
-  if (fabs (tmp - 1.0) > GSL_DBL_EPSILON)
+
+  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)
     {
-      gsl_vector_set (result, j, tmp);
+      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;
     }
-  free (subs);
 
   return result;
 }
+
+
+bool
+interaction_case_is_missing (const struct interaction *iact, const struct ccase *c, enum mv_class exclude)
+{
+  int i;
+  bool missing = false;
+
+  for (i = 0; i < iact->n_vars; ++i)
+    {
+      if ( var_is_value_missing (iact->vars[i], case_data (c, iact->vars[i]), exclude))
+	{
+	  missing = true;
+	  break;
+	}
+    }
+
+  return missing;
+}
+