--- /dev/null
+/* PSPP - a program for statistical analysis.
+ Copyright (C) 2011 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 "language/commands/ks-one-sample.h"
+
+#include <gsl/gsl_cdf.h>
+#include <math.h>
+#include <stdlib.h>
+
+
+#include "math/sort.h"
+#include "data/case.h"
+#include "data/casereader.h"
+#include "data/dataset.h"
+#include "data/dictionary.h"
+#include "data/format.h"
+#include "data/value-labels.h"
+#include "data/variable.h"
+#include "language/commands/freq.h"
+#include "language/commands/npar.h"
+#include "libpspp/array.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "libpspp/compiler.h"
+#include "libpspp/hash-functions.h"
+#include "libpspp/message.h"
+#include "libpspp/misc.h"
+#include "output/pivot-table.h"
+
+#include "gl/xalloc.h"
+
+#include "gettext.h"
+#define N_(msgid) msgid
+#define _(msgid) gettext (msgid)
+
+
+/* The per test variable statistics */
+struct ks
+{
+ double obs_cc;
+
+ double test_min ;
+ double test_max;
+ double mu;
+ double sigma;
+
+ double diff_pos;
+ double diff_neg;
+
+ double ssq;
+ double sum;
+};
+
+typedef double theoretical (const struct ks *ks, double x);
+typedef theoretical *theoreticalfp;
+
+static double
+theoretical_uniform (const struct ks *ks, double x)
+{
+ return gsl_cdf_flat_P (x, ks->test_min, ks->test_max);
+}
+
+static double
+theoretical_normal (const struct ks *ks, double x)
+{
+ return gsl_cdf_gaussian_P (x - ks->mu, ks->sigma);
+}
+
+static double
+theoretical_poisson (const struct ks *ks, double x)
+{
+ return gsl_cdf_poisson_P (x, ks->mu);
+}
+
+static double
+theoretical_exponential (const struct ks *ks, double x)
+{
+ return gsl_cdf_exponential_P (x, 1/ks->mu);
+}
+
+
+static const theoreticalfp theoreticalf[4] =
+{
+ theoretical_normal,
+ theoretical_uniform,
+ theoretical_poisson,
+ theoretical_exponential
+};
+
+/*
+ Return the assymptotic approximation to the significance of Z
+ */
+static double
+ks_asymp_sig (double z)
+{
+ if (z < 0.27)
+ return 1;
+
+ if (z >= 3.1)
+ return 0;
+
+ if (z < 1)
+ {
+ double q = exp (-1.233701 * pow (z, -2));
+ return 1 - 2.506628 * (q + pow (q, 9) + pow (q, 25))/ z ;
+ }
+ else
+ {
+ double q = exp (-2 * z * z);
+ return 2 * (q - pow (q, 4) + pow (q, 9) - pow (q, 16))/ z ;
+ }
+}
+
+static void show_results (const struct ks *, const struct ks_one_sample_test *, const struct fmt_spec *);
+
+
+void
+ks_one_sample_execute (const struct dataset *ds,
+ struct casereader *input,
+ enum mv_class exclude,
+ const struct npar_test *test,
+ bool x UNUSED, double y UNUSED)
+{
+ const struct dictionary *dict = dataset_dict (ds);
+ const struct ks_one_sample_test *kst = UP_CAST (test, const struct ks_one_sample_test, parent.parent);
+ const struct one_sample_test *ost = &kst->parent;
+ struct ccase *c;
+ const struct fmt_spec *wfmt = dict_get_weight_format (dict);
+ bool warn = true;
+ int v;
+ struct casereader *r = casereader_clone (input);
+
+ struct ks *ks = XCALLOC (ost->n_vars, struct ks);
+
+ for (v = 0; v < ost->n_vars; ++v)
+ {
+ ks[v].obs_cc = 0;
+ ks[v].test_min = DBL_MAX;
+ ks[v].test_max = -DBL_MAX;
+ ks[v].diff_pos = -DBL_MAX;
+ ks[v].diff_neg = DBL_MAX;
+ ks[v].sum = 0;
+ ks[v].ssq = 0;
+ }
+
+ for (; (c = casereader_read (r)) != NULL; case_unref (c))
+ {
+ const double weight = dict_get_case_weight (dict, c, &warn);
+
+ for (v = 0; v < ost->n_vars; ++v)
+ {
+ const struct variable *var = ost->vars[v];
+ const union value *val = case_data (c, var);
+
+ if (var_is_value_missing (var, val) & exclude)
+ continue;
+
+ minimize (&ks[v].test_min, val->f);
+ maximize (&ks[v].test_max, val->f);
+
+ ks[v].obs_cc += weight;
+ ks[v].sum += val->f;
+ ks[v].ssq += pow2 (val->f);
+ }
+ }
+ casereader_destroy (r);
+
+ for (v = 0; v < ost->n_vars; ++v)
+ {
+ const struct variable *var = ost->vars[v];
+ double cc = 0;
+ double prev_empirical = 0;
+
+ switch (kst->dist)
+ {
+ case KS_UNIFORM:
+ if (kst->p[0] != SYSMIS)
+ ks[v].test_min = kst->p[0];
+
+ if (kst->p[1] != SYSMIS)
+ ks[v].test_max = kst->p[1];
+ break;
+ case KS_NORMAL:
+ if (kst->p[0] != SYSMIS)
+ ks[v].mu = kst->p[0];
+ else
+ ks[v].mu = ks[v].sum / ks[v].obs_cc;
+
+ if (kst->p[1] != SYSMIS)
+ ks[v].sigma = kst->p[1];
+ else
+ {
+ ks[v].sigma = ks[v].ssq - pow2 (ks[v].sum) / ks[v].obs_cc;
+ ks[v].sigma /= ks[v].obs_cc - 1;
+ ks[v].sigma = sqrt (ks[v].sigma);
+ }
+
+ break;
+ case KS_POISSON:
+ case KS_EXPONENTIAL:
+ if (kst->p[0] != SYSMIS)
+ ks[v].mu = ks[v].sigma = kst->p[0];
+ else
+ ks[v].mu = ks[v].sigma = ks[v].sum / ks[v].obs_cc;
+ break;
+ default:
+ NOT_REACHED ();
+ }
+
+ r = sort_execute_1var (casereader_clone (input), var);
+ for (; (c = casereader_read (r)) != NULL; case_unref (c))
+ {
+ double theoretical, empirical;
+ double d, dp;
+ const double weight = dict_get_case_weight (dict, c, &warn);
+ const union value *val = case_data (c, var);
+
+ if (var_is_value_missing (var, val) & exclude)
+ continue;
+
+ cc += weight;
+
+ empirical = cc / ks[v].obs_cc;
+
+ theoretical = theoreticalf[kst->dist] (&ks[v], val->f);
+
+ d = empirical - theoretical;
+ dp = prev_empirical - theoretical;
+
+ if (d > 0)
+ maximize (&ks[v].diff_pos, d);
+ else
+ minimize (&ks[v].diff_neg, d);
+
+ if (dp > 0)
+ maximize (&ks[v].diff_pos, dp);
+ else
+ minimize (&ks[v].diff_neg, dp);
+
+ prev_empirical = empirical;
+ }
+
+ casereader_destroy (r);
+ }
+
+ show_results (ks, kst, wfmt);
+
+ free (ks);
+ casereader_destroy (input);
+}
+
+
+static void
+show_results (const struct ks *ks,
+ const struct ks_one_sample_test *kst,
+ const struct fmt_spec *wfmt)
+{
+ struct pivot_table *table = pivot_table_create (
+ N_("One-Sample Kolmogorov-Smirnov Test"));
+ pivot_table_set_weight_format (table, wfmt);
+
+ struct pivot_dimension *statistics = pivot_dimension_create (
+ table, PIVOT_AXIS_ROW, N_("Statistics"),
+ N_("N"), PIVOT_RC_COUNT);
+
+ switch (kst->dist)
+ {
+ case KS_UNIFORM:
+ pivot_category_create_group (statistics->root, N_("Uniform Parameters"),
+ N_("Minimum"), N_("Maximum"));
+ break;
+
+ case KS_NORMAL:
+ pivot_category_create_group (statistics->root, N_("Normal Parameters"),
+ N_("Mean"), N_("Std. Deviation"));
+ break;
+
+ case KS_POISSON:
+ pivot_category_create_group (statistics->root, N_("Poisson Parameters"),
+ N_("Lambda"));
+ break;
+
+ case KS_EXPONENTIAL:
+ pivot_category_create_group (statistics->root,
+ N_("Exponential Parameters"), N_("Scale"));
+ break;
+
+ default:
+ NOT_REACHED ();
+ }
+
+ pivot_category_create_group (
+ statistics->root, N_("Most Extreme Differences"),
+ N_("Absolute"), N_("Positive"), N_("Negative"));
+
+ pivot_category_create_leaves (
+ statistics->root, N_("Kolmogorov-Smirnov Z"),
+ _("Asymp. Sig. (2-tailed)"), PIVOT_RC_SIGNIFICANCE);
+
+ struct pivot_dimension *variables = pivot_dimension_create (
+ table, PIVOT_AXIS_COLUMN, N_("Variables"));
+
+ for (size_t i = 0; i < kst->parent.n_vars; ++i)
+ {
+ int col = pivot_category_create_leaf (
+ variables->root, pivot_value_new_variable (kst->parent.vars[i]));
+
+ double values[10];
+ size_t n = 0;
+
+ values[n++] = ks[i].obs_cc;
+
+ switch (kst->dist)
+ {
+ case KS_UNIFORM:
+ values[n++] = ks[i].test_min;
+ values[n++] = ks[i].test_max;
+ break;
+
+ case KS_NORMAL:
+ values[n++] = ks[i].mu;
+ values[n++] = ks[i].sigma;
+ break;
+
+ case KS_POISSON:
+ case KS_EXPONENTIAL:
+ values[n++] = ks[i].mu;
+ break;
+
+ default:
+ NOT_REACHED ();
+ }
+
+ double abs = ks[i].diff_pos;
+ maximize (&abs, -ks[i].diff_neg);
+
+ double z = sqrt (ks[i].obs_cc) * abs;
+
+ values[n++] = abs;
+ values[n++] = ks[i].diff_pos;
+ values[n++] = ks[i].diff_neg;
+ values[n++] = z;
+ values[n++] = ks_asymp_sig (z);
+
+ for (size_t j = 0; j < n; j++)
+ pivot_table_put2 (table, j, col, pivot_value_new_number (values[j]));
+ }
+
+ pivot_table_submit (table);
+}