csympy.pyx

   1 cdef extern from "stdlib.h":
   2     ctypedef int size_t
   3     void *malloc (size_t size)
   4
   5 cdef extern from "Python.h":
   6     ctypedef void PyObject
   7     void Py_INCREF(PyObject *x)
   8     void Py_DECREF(PyObject *x)
   9
  10 cdef extern from "stdint.h":
  11     ctypedef long long int64_t
  12     ctypedef int64_t sympyint
  13
  14 cdef extern from "glib.h":
  15     ctypedef unsigned guint
  16     ctypedef void *gconstpointer
  17     ctypedef void *gpointer
  18     ctypedef int gboolean
  19     guint g_int_hash(gconstpointer v)
  20     guint g_str_hash(gconstpointer v)
  21
  22     ctypedef struct GHashTable
  23     ctypedef struct GHashTableIter:
  24         pass
  25     #guint (*GHashFunc) (gconstpointer key)
  26     #gboolean (*GEqualFunc) (gconstpointer a, gconstpointer b)
  27     ctypedef void * GHashFunc
  28     ctypedef void * GEqualFunc
  29
  30     GHashTable *g_hash_table_new(GHashFunc hash_func, GEqualFunc key_equal_func)
  31     void g_hash_table_insert(GHashTable *hash_table,
  32             gpointer key, gpointer value)
  33     gpointer g_hash_table_lookup(GHashTable *hash_table, gconstpointer key)
  34     guint g_hash_table_size(GHashTable *hash_table)
  35     void g_hash_table_destroy(GHashTable *hash_table)
  36     void g_hash_table_iter_init(GHashTableIter *iter, GHashTable *hash_table)
  37     gboolean g_hash_table_iter_next(GHashTableIter *iter,
  38             gpointer *key, gpointer *value)
  39
  40 def int_hash(int v):
  41     return g_int_hash(&v)
  42
  43 def str_hash(char *v):
  44     return g_str_hash(v)
  45
  46 cdef class Table:
  47     cdef GHashTable *thisptr
  48
  49     def __init__(self):
  50         self.thisptr = g_hash_table_new(NULL, NULL)
  51
  52     def __dealloc__(self):
  53         g_hash_table_destroy(self.thisptr)
  54
  55     def __setitem__(self, x, y):
  56         self.insert(x, y)
  57
  58     def __getitem__(self, x):
  59         return self.get(x)
  60
  61     def __contains__(self, x):
  62         try:
  63             self.get(x)
  64         except KeyError:
  65             return False
  66         return True
  67
  68     def __len__(self):
  69         return g_hash_table_size(self.thisptr)
  70
  71     def insert(self, key, coeff):
  72         g_hash_table_insert(self.thisptr, <gpointer>key, <gpointer>coeff)
  73         # Without the following it sometimes segfaults, but maybe the INCREF
  74         # should be put at some other place:
  75         Py_INCREF(<PyObject *>key)
  76         Py_INCREF(<PyObject *>coeff)
  77
  78     def get(self, key):
  79         cdef gpointer value
  80         value = g_hash_table_lookup(self.thisptr, <gconstpointer>key)
  81         if value == NULL:
  82             raise KeyError(key)
  83         return <object>value
  84
  85     def iteritems(self):
  86         cdef GHashTableIter iter
  87
  88         g_hash_table_iter_init (&iter, self.thisptr);
  89         cdef gpointer key, value
  90
  91         a = []
  92         while g_hash_table_iter_next(&iter, &key, &value):
  93             a.append((<object>key, <object>value))
  94         return a
  95
  96 cdef guint my_hash(gconstpointer v):
  97     o= <object>v
  98     return hash(o)
  99
 100 cdef gboolean my_equal(gconstpointer a, gconstpointer b):
 101     o1 = <object>a
 102     o2 = <object>b
 103     return o1 == o2
 104
 105
 106 cdef class HashTable(Table):
 107
 108     def __init__(self):
 109         self.thisptr = g_hash_table_new(&my_hash, &my_equal)