C++ (Cpp) igraph_es_1の例

コード例 #1

ファイル: model.c プロジェクト: vpong/Research-in-Math

void iterate(igraph_t *graph, double th)
{
    igraph_integer_t x, y, z = -1.0, xy;
    
    xy = rand() % (int) igraph_ecount(graph);
    igraph_edge(graph, xy, &x, &y);

    //flip increasing orientation with pr 1/2
    if(rand() % 2)
    {
        igraph_integer_t buffer = y;
        y = x;
        x = buffer;
    }

    igraph_vector_t degrees;
    igraph_vector_init(&degrees, 1); 
    all_degrees(graph, &degrees);


    double d_mean = get_d_mean(graph);
    double random = 1.0 * rand() / RAND_MAX;
    int w;
    double total = 0.0;
    double denom = get_denom(graph, &degrees, th, x, y); 

    for(w = 0; w < igraph_vector_size(&degrees); w++)
    {
        if(w != (int) x && w != (int) y)
        {
            total += f(VECTOR(degrees)[w], d_mean, th) / denom; 

            if(random < total)
            {
                z = (igraph_integer_t) w;
                break;
            }
        }
    }

    igraph_vector_destroy(&degrees);

    if(z > -.5)
    {
        igraph_es_t es;

        igraph_es_1(&es, xy);
        igraph_delete_edges(graph, es);
        igraph_es_destroy(&es);

        igraph_add_edge(graph, x, z);
    } 
}

コード例 #2

ファイル: edgeseqobject.c プロジェクト: bravery/python-igraph

/**
 * \ingroup python_interface_edgeseq
 * \brief Initialize a new edge sequence object for a given graph
 * \return the initialized PyObject
 */
int igraphmodule_EdgeSeq_init(igraphmodule_EdgeSeqObject *self,
  PyObject *args, PyObject *kwds) {
  static char *kwlist[] = { "graph", "edges", NULL };
  PyObject *g, *esobj=Py_None;
  igraph_es_t es;

  if (!PyArg_ParseTupleAndKeywords(args, kwds, "O!|O", kwlist,
    &igraphmodule_GraphType, &g, &esobj))
      return -1;

  if (esobj == Py_None) {
    /* If es is None, we are selecting all the edges */
    igraph_es_all(&es, IGRAPH_EDGEORDER_ID);
  } else if (PyInt_Check(esobj)) {
    /* We selected a single edge */
    long int idx = PyInt_AsLong(esobj);
    if (idx < 0 || idx >= igraph_ecount(&((igraphmodule_GraphObject*)g)->g)) {
      PyErr_SetString(PyExc_ValueError, "edge index out of range");
      return -1;
    }
    igraph_es_1(&es, (igraph_integer_t)idx);
  } else {
	/* We selected multiple edges */
    igraph_vector_t v;
    igraph_integer_t n = igraph_ecount(&((igraphmodule_GraphObject*)g)->g);
    if (igraphmodule_PyObject_to_vector_t(esobj, &v, 1))
      return -1;
    if (!igraph_vector_isininterval(&v, 0, n-1)) {
      igraph_vector_destroy(&v);
      PyErr_SetString(PyExc_ValueError, "edge index out of range");
      return -1;
    }
    if (igraph_es_vector_copy(&es, &v)) {
      igraphmodule_handle_igraph_error();
      igraph_vector_destroy(&v);
      return -1;
    }
    igraph_vector_destroy(&v);
  }

  self->es = es;
  Py_INCREF(g);
  self->gref = (igraphmodule_GraphObject*)g;

  return 0;
}