--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/gis/geos/coordseq.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,164 @@
+"""
+ This module houses the GEOSCoordSeq object, which is used internally
+ by GEOSGeometry to house the actual coordinates of the Point,
+ LineString, and LinearRing geometries.
+"""
+from ctypes import c_double, c_uint, byref
+from types import ListType, TupleType
+from django.contrib.gis.geos.error import GEOSException, GEOSIndexError
+from django.contrib.gis.geos.libgeos import CS_PTR, HAS_NUMPY
+from django.contrib.gis.geos.prototypes import cs_clone, cs_getdims, cs_getordinate, cs_getsize, cs_setordinate
+if HAS_NUMPY: from numpy import ndarray
+
+class GEOSCoordSeq(object):
+    "The internal representation of a list of coordinates inside a Geometry."
+
+    #### Python 'magic' routines ####
+    def __init__(self, ptr, z=False):
+        "Initializes from a GEOS pointer."
+        if not isinstance(ptr, CS_PTR):
+            raise TypeError('Coordinate sequence should initialize with a CS_PTR.')
+        self._ptr = ptr
+        self._z = z
+
+    def __iter__(self):
+        "Iterates over each point in the coordinate sequence."
+        for i in xrange(self.size):
+            yield self[i]
+
+    def __len__(self):
+        "Returns the number of points in the coordinate sequence."
+        return int(self.size)
+
+    def __str__(self):
+        "Returns the string representation of the coordinate sequence."
+        return str(self.tuple)
+
+    def __getitem__(self, index):
+        "Returns the coordinate sequence value at the given index."
+        coords = [self.getX(index), self.getY(index)]
+        if self.dims == 3 and self._z:
+            coords.append(self.getZ(index))
+        return tuple(coords)
+
+    def __setitem__(self, index, value):
+        "Sets the coordinate sequence value at the given index."
+        # Checking the input value
+        if isinstance(value, (ListType, TupleType)):
+            pass
+        elif HAS_NUMPY and isinstance(value, ndarray):
+            pass
+        else:
+            raise TypeError('Must set coordinate with a sequence (list, tuple, or numpy array).')
+        # Checking the dims of the input
+        if self.dims == 3 and self._z:
+            n_args = 3
+            set_3d = True
+        else:
+            n_args = 2
+            set_3d = False
+        if len(value) != n_args:
+            raise TypeError('Dimension of value does not match.')
+        # Setting the X, Y, Z
+        self.setX(index, value[0])
+        self.setY(index, value[1])
+        if set_3d: self.setZ(index, value[2])
+
+    #### Internal Routines ####
+    def _checkindex(self, index):
+        "Checks the given index."
+        sz = self.size
+        if (sz < 1) or (index < 0) or (index >= sz):
+            raise GEOSIndexError('invalid GEOS Geometry index: %s' % str(index))
+
+    def _checkdim(self, dim):
+        "Checks the given dimension."
+        if dim < 0 or dim > 2:
+            raise GEOSException('invalid ordinate dimension "%d"' % dim)
+
+    @property
+    def ptr(self):
+        """
+        Property for controlling access to coordinate sequence pointer,
+        preventing attempted access to a NULL memory location.
+        """
+        if self._ptr: return self._ptr
+        else: raise GEOSException('NULL coordinate sequence pointer encountered.')
+
+    #### Ordinate getting and setting routines ####
+    def getOrdinate(self, dimension, index):
+        "Returns the value for the given dimension and index."
+        self._checkindex(index)
+        self._checkdim(dimension)
+        return cs_getordinate(self.ptr, index, dimension, byref(c_double()))
+
+    def setOrdinate(self, dimension, index, value):
+        "Sets the value for the given dimension and index."
+        self._checkindex(index)
+        self._checkdim(dimension)
+        cs_setordinate(self.ptr, index, dimension, value)
+
+    def getX(self, index):
+        "Get the X value at the index."
+        return self.getOrdinate(0, index)
+
+    def setX(self, index, value):
+        "Set X with the value at the given index."
+        self.setOrdinate(0, index, value)
+
+    def getY(self, index):
+        "Get the Y value at the given index."
+        return self.getOrdinate(1, index)
+
+    def setY(self, index, value):
+        "Set Y with the value at the given index."
+        self.setOrdinate(1, index, value)
+
+    def getZ(self, index):
+        "Get Z with the value at the given index."
+        return self.getOrdinate(2, index)
+
+    def setZ(self, index, value):
+        "Set Z with the value at the given index."
+        self.setOrdinate(2, index, value)
+
+    ### Dimensions ###
+    @property
+    def size(self):
+        "Returns the size of this coordinate sequence."
+        return cs_getsize(self.ptr, byref(c_uint()))
+
+    @property
+    def dims(self):
+        "Returns the dimensions of this coordinate sequence."
+        return cs_getdims(self.ptr, byref(c_uint()))
+
+    @property
+    def hasz(self):
+        """
+        Returns whether this coordinate sequence is 3D.  This property value is
+        inherited from the parent Geometry.
+        """
+        return self._z
+
+    ### Other Methods ###
+    def clone(self):
+        "Clones this coordinate sequence."
+        return GEOSCoordSeq(cs_clone(self.ptr), self.hasz)
+
+    @property
+    def kml(self):
+        "Returns the KML representation for the coordinates."
+        # Getting the substitution string depending on whether the coordinates have
+        #  a Z dimension.
+        if self.hasz: substr = '%s,%s,%s '
+        else: substr = '%s,%s,0 '
+        return '<coordinates>%s</coordinates>' % \
+            ''.join([substr % self[i] for i in xrange(len(self))]).strip()
+
+    @property
+    def tuple(self):
+        "Returns a tuple version of this coordinate sequence."
+        n = self.size
+        if n == 1: return self[0]
+        else: return tuple([self[i] for i in xrange(n)])