-/* PSPP - Creates data structures to store interactions for
- statistical routines.
+/* PSPP - a program for statistical analysis.
+ Copyright (C) 2011 Free Software Foundation, Inc.
- Copyright (C) 2007 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 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 2 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.
+ 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, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include <config.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.
- */
-#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>
/*
- Convert a list of values to a binary vector. The order of VALS must
- correspond to the order of V.
- */
-gsl_vector *
-get_interaction (union value **vals, const struct variable **v, size_t n_vars)
+ 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)
{
- gsl_vector *result = NULL;
- size_t *subs = NULL;
- size_t length = 1;
- size_t i;
- size_t j;
- double tmp = 1.0;
-
- assert (n_vars > 0);
- for (i = 0; i < n_vars; i++)
- {
- if (var_is_alpha (v[i]))
- {
- length *= cat_get_n_categories (v[i]);
- }
- else
- {
- length = (length > 0) ? length : 1;
- }
- }
- if (length > 0)
+ struct interaction *i = xmalloc (sizeof *i);
+ i->vars = xmalloc (sizeof *i->vars);
+ i->vars[0] = v;
+ i->n_vars = 1;
+ return i;
+}
+
+void
+interaction_destroy (struct interaction *i)
+{
+ 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;
+}
+
+
+void
+interaction_dump (const struct interaction *i)
+{
+ int v = 0;
+ printf ("%s", var_get_name (i->vars[v]));
+ for (v = 1; v < i->n_vars; ++v)
{
- length--;
+ printf (" * %s", var_get_name (i->vars[v]));
}
+ printf ("\n");
+}
+
+/* Appends STR with a representation of the interaction, suitable for user
+ display.
- result = gsl_vector_calloc (length);
- subs = xnmalloc (n_vars, sizeof (*subs));
- for (j = 0; j < n_vars; j++)
+ STR must have been initialised prior to calling this function.
+*/
+void
+interaction_to_string (const struct interaction *iact, struct string *str)
+{
+ int v = 0;
+ 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_value_hash (const struct interaction *iact, const union value *val)
+{
+ int i;
+ size_t hash = 0;
+ for (i = 0; i < iact->n_vars; ++i)
{
- j = j * cat_get_n_categories (v[i]) + subs[i];
+ hash = value_hash (&val[i], var_get_width (iact->vars[i]), 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_value_equal (const struct interaction *iact, const union value *val1, const union value *val2)
+{
+ int i;
+ bool same = true;
+
+ for (i = 0; i < iact->n_vars; ++i)
{
- if (var_is_numeric (v[i]))
+ if ( ! value_equal (&val1[i], &val2[i], var_get_width (iact->vars[i])))
{
- tmp *= vals[i]->f;
+ same = false;
+ break;
}
}
- if (fabs (tmp - 1.0) > GSL_DBL_EPSILON)
+
+ return same;
+}
+
+
+bool
+interaction_value_is_missing (const struct interaction *iact, const union value *val, enum mv_class exclude)
+{
+ int i;
+ bool missing = false;
+
+ for (i = 0; i < iact->n_vars; ++i)
{
- gsl_vector_set (result, j, tmp);
+ if ( var_is_value_missing (iact->vars[i], &val[i], exclude))
+ {
+ missing = true;
+ break;
+ }
}
- free (subs);
- return result;
+ return missing;
}
projects / pspp-builds.git / blobdiff