/* PSPP - a program for statistical analysis.
- Copyright (C) 2009 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
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 structure 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.
-
- When using these functions, make sure the orders of variables and
- values match when appropriate.
- */
+ variables. The variables can be either string or numeric.
-#include <config.h>
-#include <assert.h>
-#include <data/value.h>
-#include <data/variable.h>
-#include <gl/unistr.h>
-#include <math/interaction.h>
-#include <string.h>
-#include <xalloc.h>
-
-struct interaction_variable
-{
- int n_vars;
- const struct variable **members;
- struct variable *intr;
- size_t n_alpha;
-};
+ 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_value
+
+struct interaction *
+interaction_create (const struct variable *v)
{
- const struct interaction_variable *intr;
- union value val; /* Concatenation of the string values in this
- interaction's value, or the product of a bunch
- of numeric values for a purely numeric
- interaction.
- */
- double f; /* Product of the numerical values in this interaction's value. */
-};
+ 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;
+}
-/*
- An interaction_variable has type alpha if any of members have type
- alpha. Otherwise, its type is numeric.
- */
-struct interaction_variable *
-interaction_variable_create (const struct variable **vars, int n_vars)
+/* Deep copy an interaction */
+struct interaction *
+interaction_clone (const struct interaction *iact)
{
- struct interaction_variable *result = NULL;
- size_t i;
+ int v;
+ struct interaction *i = xmalloc (sizeof *i);
+ i->vars = xcalloc (iact->n_vars, sizeof *i->vars);
+ i->n_vars = iact->n_vars;
- if (n_vars > 0)
+ for (v = 0; v < iact->n_vars; ++v)
{
- int width = 0;
-
- result = xmalloc (sizeof (*result));
- result->n_alpha = 0;
- result->members = xnmalloc (n_vars, sizeof (*result->members));
- result->n_vars = n_vars;
- for (i = 0; i < n_vars; i++)
- {
- result->members[i] = vars[i];
- if (var_is_alpha (vars[i]))
- {
- result->n_alpha++;
- width += var_get_width (vars[i]);
- }
- }
- result->intr = var_create_internal (0, width);
+ i->vars[v] = iact->vars[v];
}
- return result;
-}
-void interaction_variable_destroy (struct interaction_variable *iv)
-{
- var_destroy (iv->intr);
- free (iv->members);
- free (iv);
+ return i;
}
-/*
- Get one of the member variables.
- */
-const struct variable *
-interaction_get_member (const struct interaction_variable *iv, size_t i)
-{
- return iv->members[i];
-}
-size_t
-interaction_get_n_vars (const struct interaction_variable *iv)
+void
+interaction_destroy (struct interaction *i)
{
- return (iv == NULL) ? 0 : iv->n_vars;
-}
+ if (NULL == i)
+ return;
-size_t
-interaction_get_n_alpha (const struct interaction_variable *iv)
-{
- return iv->n_alpha;
+ free (i->vars);
+ free (i);
}
-size_t
-interaction_get_n_numeric (const struct interaction_variable *iv)
+void
+interaction_add_variable (struct interaction *i, const struct variable *v)
{
- return (interaction_get_n_vars (iv) - interaction_get_n_alpha (iv));
+ i->vars = xrealloc (i->vars, sizeof (*i->vars) * ++i->n_vars);
+ i->vars[i->n_vars - 1] = v;
}
+
/*
- Get the interaction variable itself.
+ Do the variables in X->VARS constitute a proper
+ subset of the variables in Y->VARS?
*/
-const struct variable *
-interaction_get_variable (const struct interaction_variable *iv)
+bool
+interaction_is_proper_subset (const struct interaction *x, const struct interaction *y)
{
- return iv->intr;
+ if (x->n_vars >= y->n_vars)
+ return false;
+
+ return interaction_is_subset (x, y);
}
+
/*
- Given list of values, compute the value of the corresponding
- interaction. This "value" is not stored as the typical vector of
- 0's and one double, but rather the string values are concatenated to
- make one big string value, and the numerical values are multiplied
- together to give the non-zero entry of the corresponding vector.
+ Do the variables in X->VARS constitute a
+ subset (proper or otherwise) of the variables in Y->VARS?
*/
-struct interaction_value *
-interaction_value_create (const struct interaction_variable *var, const union value **vals)
+bool
+interaction_is_subset (const struct interaction *x, const struct interaction *y)
{
- struct interaction_value *result = NULL;
-
- if (var != NULL)
- {
- size_t i;
- int val_width = var_get_width (interaction_get_variable (var));
- int offset = 0;
- size_t n_vars = interaction_get_n_vars (var);
-
- result = xmalloc (sizeof (*result));
- result->intr = var;
+ size_t i;
+ size_t j;
+ size_t n = 0;
- value_init (&result->val, val_width);
+ /* By definition, a subset cannot have more members than its superset */
+ if (x->n_vars > y->n_vars)
+ return false;
- result->f = 1.0;
- for (i = 0; i < n_vars; i++)
+ /* Count the number of values which are members of both sets */
+ for (i = 0; i < x->n_vars; i++)
+ {
+ for (j = 0; j < y->n_vars; j++)
{
- const struct variable *member = interaction_get_member (var, i);
-
- if (var_is_value_missing (member, vals[i], MV_ANY))
+ if (x->vars [i] == y->vars [j])
{
- value_set_missing (&result->val, val_width);
- result->f = SYSMIS;
- break;
+ n++;
}
- else
- {
- if (var_is_alpha (var->members[i]))
- {
- uint8_t *val = value_str_rw (&result->val, val_width);
- int w = var_get_width (var->members[i]);
- u8_cpy (val + offset, value_str (vals[i], w), w);
- offset += w;
- }
- else if (var_is_numeric (var->members[i]))
- {
- result->f *= vals[i]->f;
- }
- }
- }
- if (interaction_get_n_alpha (var) == 0)
- {
- /*
- If there are no categorical variables, then the
- interaction consists of only numeric data. In this case,
- code that uses this interaction_value will see the union
- member as the numeric value. If we were to store that
- numeric value in result->f as well, the calling code may
- inadvertently square this value by multiplying by
- result->val->f. Such multiplication would be correct for an
- interaction consisting of both categorical and numeric
- data, but a mistake for purely numerical interactions. To
- avoid the error, we set result->f to 1.0 for numeric
- interactions.
- */
- result->val.f = result->f;
- result->f = 1.0;
}
}
- return result;
+
+ /* 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;
}
-const union value *
-interaction_value_get (const struct interaction_value *val)
+
+
+
+void
+interaction_dump (const struct interaction *i)
{
- return &val->val;
+ int v = 0;
+ if ( i->n_vars == 0)
+ {
+ 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");
}
-/*
- Returns the numeric value of the non-zero entry for the vector
- corresponding to this interaction. Do not use this function to get
- the numeric value of a purely numeric interaction. Instead, use the
- union value * returned by interaction_value_get.
- */
-double
-interaction_value_get_nonzero_entry (const struct interaction_value *val)
+/* 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)
{
- if (val != NULL)
- return val->f;
- return 1.0;
+ 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)
+ {
+ ds_put_cstr (str, " * ");
+ ds_put_cstr (str, var_to_string (iact->vars[v]));
+ }
}
-void
-interaction_value_destroy (struct interaction_value *val)
+unsigned int
+interaction_case_hash (const struct interaction *iact, const struct ccase *c, unsigned int base)
{
- if (val != NULL)
+ int i;
+ size_t hash = base;
+ for (i = 0; i < iact->n_vars; ++i)
{
- int val_width = var_get_width (interaction_get_variable (val->intr));
-
- value_destroy (&val->val, val_width);
- free (val);
+ const struct variable *var = iact->vars[i];
+ const union value *val = case_data (c, var);
+ hash = value_hash (val, var_get_width (var), hash);
}
+ return hash;
}
-/*
- Return a value from a variable that is an interaction.
- */
-struct interaction_value *
-interaction_case_data (const struct ccase *ccase, const struct interaction_variable *iv)
+bool
+interaction_case_equal (const struct interaction *iact, const struct ccase *c1, const struct ccase *c2)
{
- size_t i;
- size_t n_vars;
- const struct variable *member;
- const union value **vals = NULL;
-
- n_vars = interaction_get_n_vars (iv);
- vals = xnmalloc (n_vars, sizeof (*vals));
+ int i;
+ bool same = true;
- for (i = 0; i < n_vars; i++)
+ for (i = 0; i < iact->n_vars; ++i)
+ {
+ const struct variable *var = iact->vars[i];
+ if ( ! value_equal (case_data (c1, var), case_data (c2, var), var_get_width (var)))
{
- member = interaction_get_member (iv, i);
- vals[i] = case_data (ccase, member);
+ same = false;
+ break;
}
+ }
+
+ return same;
+}
+
+
+int
+interaction_case_cmp_3way (const struct interaction *iact, const struct ccase *c1, const struct ccase *c2)
+{
+ int i;
+ int result = 0;
- return interaction_value_create (iv, vals);
+ 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
-is_interaction (const struct variable *var, const struct interaction_variable **iv, size_t n_intr)
+interaction_case_is_missing (const struct interaction *iact, const struct ccase *c, enum mv_class exclude)
{
- size_t i;
- const struct variable *intr;
-
- for (i = 0; i < n_intr; i++)
+ int i;
+ bool missing = false;
+
+ for (i = 0; i < iact->n_vars; ++i)
{
- intr = interaction_get_variable (iv[i]);
- if (var_get_dict_index (intr) == var_get_dict_index (var))
+ if ( var_is_value_missing (iact->vars[i], case_data (c, iact->vars[i]), exclude))
{
- return true;
+ missing = true;
+ break;
}
}
- return false;
+
+ return missing;
}
-
+