Add graph references

2026-06-28 13:49:01 +01:00
parent 0a9807e448
commit a11edf0c53
2578 changed files with 868045 additions and 0 deletions
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+/*
+   igraph library.
+   Copyright (C) 2009-2025  The igraph development team <igraph@igraph.org>
+
+   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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef IGRAPH_NONGRAPH_H
+#define IGRAPH_NONGRAPH_H
+
+#include "igraph_decls.h"
+#include "igraph_error.h"
+#include "igraph_types.h"
+#include "igraph_vector.h"
+
+IGRAPH_BEGIN_C_DECLS
+
+/**
+ * \def IGRAPH_SHORTEST_PATH_EPSILON
+ *
+ * Relative error threshold used in weighted shortest path calculations
+ * to decide whether two shortest paths are of equal length.
+ */
+#define IGRAPH_SHORTEST_PATH_EPSILON 1e-10
+
+/* -------------------------------------------------- */
+/* Other, not graph related                           */
+/* -------------------------------------------------- */
+
+/**
+ * \struct igraph_plfit_result_t
+ * \brief Result of fitting a power-law distribution to a vector.
+ *
+ * This data structure contains the result of \ref igraph_power_law_fit(),
+ * which tries to fit a power-law distribution to a vector of numbers. The
+ * structure contains the following members:
+ *
+ * \member continuous Whether the fitted power-law distribution was continuous
+ *                    or discrete.
+ * \member alpha The exponent of the fitted power-law distribution.
+ * \member xmin  The minimum value from which the power-law distribution was
+ *               fitted. In other words, only the values larger than \c xmin
+ *               were used from the input vector.
+ * \member L     The log-likelihood of the fitted parameters; in other words,
+ *               the probability of observing the input vector given the
+ *               parameters.
+ * \member D     The test statistic of a Kolmogorov-Smirnov test that compares
+ *               the fitted distribution with the input vector. Smaller scores
+ *               denote better fit.
+ * \member p     The p-value of the Kolmogorov-Smirnov test; \c NaN if it has
+ *               not been calculated yet. Small p-values (less than 0.05)
+ *               indicate that the test rejected the hypothesis that the
+ *               original data could have been drawn from the fitted power-law
+ *               distribution.
+ * \member data  The vector containing the original input data. May not be valid
+ *               any more if the caller already destroyed the vector.
+ */
+typedef struct igraph_plfit_result_t {
+    igraph_bool_t continuous;
+    igraph_real_t alpha;
+    igraph_real_t xmin;
+    igraph_real_t L;
+    igraph_real_t D;
+    const igraph_vector_t* data;
+} igraph_plfit_result_t;
+
+IGRAPH_EXPORT igraph_error_t igraph_running_mean(const igraph_vector_t *data, igraph_vector_t *res,
+                                      igraph_int_t binwidth);
+IGRAPH_EXPORT igraph_error_t igraph_random_sample(igraph_vector_int_t *res, igraph_int_t l, igraph_int_t h,
+                                       igraph_int_t length);
+IGRAPH_EXPORT IGRAPH_FUNCATTR_CONST igraph_bool_t igraph_almost_equals(double a, double b, double eps);
+IGRAPH_EXPORT IGRAPH_FUNCATTR_CONST int igraph_cmp_epsilon(double a, double b, double eps);
+
+IGRAPH_EXPORT igraph_error_t igraph_power_law_fit(
+    const igraph_vector_t* vector, igraph_plfit_result_t* result,
+    igraph_real_t xmin, igraph_bool_t force_continuous
+);
+IGRAPH_EXPORT igraph_error_t igraph_plfit_result_calculate_p_value(
+    const igraph_plfit_result_t* model, igraph_real_t* result, igraph_real_t precision
+);
+
+IGRAPH_END_C_DECLS
+
+#endif