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) 2010-2025  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_LAPACK_H
+#define IGRAPH_LAPACK_H
+
+#include "igraph_decls.h"
+#include "igraph_error.h"
+#include "igraph_vector.h"
+#include "igraph_matrix.h"
+
+IGRAPH_BEGIN_C_DECLS
+
+/**
+ * \section about_lapack LAPACK interface in igraph
+ *
+ * <para>
+ * LAPACK is written in Fortran90 and provides routines for solving
+ * systems of simultaneous linear equations, least-squares solutions
+ * of linear systems of equations, eigenvalue problems, and singular
+ * value problems. The associated matrix factorizations (LU, Cholesky,
+ * QR, SVD, Schur, generalized Schur) are also provided, as are
+ * related computations such as reordering of the Schur factorizations
+ * and estimating condition numbers. Dense and banded matrices are
+ * handled, but not general sparse matrices. In all areas, similar
+ * functionality is provided for real and complex matrices, in both
+ * single and double precision.
+ * </para>
+ *
+ * <para>
+ * igraph provides an interface to a very limited set of LAPACK
+ * functions, using the regular igraph data structures.
+ * </para>
+ *
+ * <para>
+ * See more about LAPACK at http://www.netlib.org/lapack/
+ * </para>
+ */
+
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgetrf(igraph_matrix_t *a, igraph_vector_int_t *ipiv,
+                                       int *info);
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgetrs(igraph_bool_t transpose, const igraph_matrix_t *a,
+                                       const igraph_vector_int_t *ipiv, igraph_matrix_t *b);
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgesv(igraph_matrix_t *a, igraph_vector_int_t *ipiv,
+                                      igraph_matrix_t *b, int *info);
+
+typedef enum { IGRAPH_LAPACK_DSYEV_ALL,
+               IGRAPH_LAPACK_DSYEV_INTERVAL,
+               IGRAPH_LAPACK_DSYEV_SELECT
+             } igraph_lapack_dsyev_which_t;
+
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dsyevr(const igraph_matrix_t *A,
+                                       igraph_lapack_dsyev_which_t which,
+                                       igraph_real_t vl, igraph_real_t vu, int vestimate,
+                                       int il, int iu, igraph_real_t abstol,
+                                       igraph_vector_t *values, igraph_matrix_t *vectors,
+                                       igraph_vector_int_t *support);
+
+/* TODO: should we use complex vectors/matrices? */
+
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgeev(const igraph_matrix_t *A,
+                                      igraph_vector_t *valuesreal,
+                                      igraph_vector_t *valuesimag,
+                                      igraph_matrix_t *vectorsleft,
+                                      igraph_matrix_t *vectorsright, int *info);
+
+typedef enum { IGRAPH_LAPACK_DGEEVX_BALANCE_NONE = 0,
+               IGRAPH_LAPACK_DGEEVX_BALANCE_PERM,
+               IGRAPH_LAPACK_DGEEVX_BALANCE_SCALE,
+               IGRAPH_LAPACK_DGEEVX_BALANCE_BOTH
+             }
+igraph_lapack_dgeevx_balance_t;
+
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgeevx(igraph_lapack_dgeevx_balance_t balance,
+                                       const igraph_matrix_t *A,
+                                       igraph_vector_t *valuesreal,
+                                       igraph_vector_t *valuesimag,
+                                       igraph_matrix_t *vectorsleft,
+                                       igraph_matrix_t *vectorsright,
+                                       int *ilo, int *ihi, igraph_vector_t *scale,
+                                       igraph_real_t *abnrm,
+                                       igraph_vector_t *rconde,
+                                       igraph_vector_t *rcondv,
+                                       int *info);
+
+IGRAPH_EXPORT igraph_error_t igraph_lapack_dgehrd(const igraph_matrix_t *A,
+                                       int ilo, int ihi,
+                                       igraph_matrix_t *result);
+
+IGRAPH_END_C_DECLS
+
+#endif