Source code for pygrass.vector.basic

# -*- coding: utf-8 -*-
Created on Tue Jul 31 13:06:20 2012

@author: pietro
import ctypes
import grass.lib.vector as libvect
from collections import Iterable

from import dict2html

[docs]class Bbox(object): """Instantiate a Bounding Box class that contains a ctypes pointer to the C struct bound_box, that could be used by C GRASS functions. >>> bbox = Bbox() >>> bbox Bbox(0.0, 0.0, 0.0, 0.0) The default parameters are 0. It is possible to set or change the parameters later, with: >>> bbox.north = 10 >>> bbox.south = -10 >>> bbox.east = -20 >>> bbox.west = 20 >>> bbox Bbox(10.0, -10.0, -20.0, 20.0) Or directly istantiate the class with the values, with: >>> bbox = Bbox(north=100, south=0, east=0, west=100) >>> bbox Bbox(100.0, 0.0, 0.0, 100.0) .. """ def __init__(self, north=0, south=0, east=0, west=0, top=0, bottom=0): self.c_bbox = ctypes.pointer(libvect.bound_box()) self.north = north self.south = south self.east = east self.west = west = top self.bottom = bottom def _get_n(self): """Private method to obtain the north value""" return self.c_bbox.contents.N def _set_n(self, value): """Private method to set the north value""" self.c_bbox.contents.N = value north = property(fget=_get_n, fset=_set_n, doc="Set and obtain north value") def _get_s(self): """Private method to obtain the south value""" return self.c_bbox.contents.S def _set_s(self, value): """Private method to set the south value""" self.c_bbox.contents.S = value south = property(fget=_get_s, fset=_set_s, doc="Set and obtain south value") def _get_e(self): """Private method to obtain the east value""" return self.c_bbox.contents.E def _set_e(self, value): """Private method to set the east value""" self.c_bbox.contents.E = value east = property(fget=_get_e, fset=_set_e, doc="Set and obtain east value") def _get_w(self): """Private method to obtain the west value""" return self.c_bbox.contents.W def _set_w(self, value): """Private method to set the west value""" self.c_bbox.contents.W = value west = property(fget=_get_w, fset=_set_w, doc="Set and obtain west value") def _get_t(self): """Private method to obtain the top value""" return self.c_bbox.contents.T def _set_t(self, value): """Private method to set the top value""" self.c_bbox.contents.T = value top = property(fget=_get_t, fset=_set_t, doc="Set and obtain top value") def _get_b(self): """Private method to obtain the bottom value""" return self.c_bbox.contents.B def _set_b(self, value): """Private method to set the bottom value""" self.c_bbox.contents.B = value bottom = property(fget=_get_b, fset=_set_b, doc="Set and obtain bottom value") def __repr__(self): return "Bbox({n}, {s}, {e}, {w})".format(n=self.north, s=self.south, e=self.east, w=self.west) def _repr_html_(self): return dict2html(dict(self.items()), keys=self.keys(), border='1', kdec='b')
[docs] def keys(self): return ['north', 'south', 'west', 'east', 'top', 'bottom']
[docs] def contains(self, point): """Return True if the object is contained by the BoundingBox :param point: the point to analyze :type point: a Point object or a tuple with the coordinates >>> from grass.pygrass.vector.geometry import Point >>> poi = Point(5,5) >>> bbox = Bbox(north=10, south=0, west=0, east=10) >>> bbox.contains(poi) True """ return bool(libvect.Vect_point_in_box(point.x, point.y, point.z if point.z else 0, self.c_bbox))
[docs] def items(self): return [(k, self.__getattribute__(k)) for k in self.keys()]
[docs] def nsewtb(self, tb=True): """Return a list of values from bounding box :param tb: if tb parameter is False return only: north, south, east, west and not top and bottom :type tb: bool """ if tb: return (self.north, self.south, self.east, self.west,, self.bottom) else: return (self.north, self.south, self.east, self.west)
[docs]class BoxList(object): """Instantiate a BoxList class to create a list of Bounding Box""" def __init__(self, boxlist=None): self.c_boxlist = ctypes.pointer(libvect.boxlist()) # if set to 0, the list will hold only ids and no boxes self.c_boxlist.contents.have_boxes = 1 if boxlist is not None: for box in boxlist: self.append(box) @property
[docs] def ids(self): return [[i] for i in range(self.n_values)]
[docs] def n_values(self): return self.c_boxlist.contents.n_values
[docs] def have_boxes(self): return bool(self.c_boxlist.contents.have_boxes)
def __len__(self): return self.c_boxlist.contents.n_values def __repr__(self): return "Boxlist([%s])" % ", ".join([repr(box) for box in self.__iter__()]) def __getitem__(self, indx): bbox = Bbox() bbox.c_bbox = ctypes.pointer([indx]) return bbox def __setitem__(self, indx, bbox):[indx] = bbox def __iter__(self): return (self.__getitem__(box_id) for box_id in range(self.__len__())) def __str__(self): return self.__repr__()
[docs] def append(self, box): """Append a Bbox object to a Boxlist object, using the ``Vect_boxlist_append`` C function. :param bbox: the bounding box to add to the list :param bbox: a Bbox object >>> box0 = Bbox() >>> box1 = Bbox(1,2,3,4) >>> box2 = Bbox(5,6,7,8) >>> boxlist = BoxList([box0, box1]) >>> boxlist Boxlist([Bbox(0.0, 0.0, 0.0, 0.0), Bbox(1.0, 2.0, 3.0, 4.0)]) >>> len(boxlist) 2 >>> boxlist.append(box2) >>> len(boxlist) 3 """ indx = self.__len__() libvect.Vect_boxlist_append(self.c_boxlist, indx, box.c_bbox) # def extend(self, boxlist): # """Extend a boxlist with another boxlist or using a list of Bbox, using # ``Vect_boxlist_append_boxlist`` c function. :: # # >>> box0 = Bbox() # >>> box1 = Bbox(1,2,3,4) # >>> box2 = Bbox(5,6,7,8) # >>> box3 = Bbox(9,8,7,6) # >>> boxlist0 = BoxList([box0, box1]) # >>> boxlist0 # Boxlist([Bbox(0.0, 0.0, 0.0, 0.0), Bbox(1.0, 2.0, 3.0, 4.0)]) # >>> boxlist1 = BoxList([box2, box3]) # >>> len(boxlist0) # 2 # >>> boxlist0.extend(boxlist1) # >>> len(boxlist0) # 4 # >>> boxlist1.extend([box0, box1]) # >>> len(boxlist1) # 4 # # .. # """ # if hasattr(boxlist, 'c_boxlist'): # #import pdb; pdb.set_trace() # # FIXME: doesn't work # libvect.Vect_boxlist_append_boxlist(self.c_boxlist, # boxlist.c_boxlist) # else: # for box in boxlist: # self.append(box)
[docs] def remove(self, indx): """Remove Bbox from the boxlist, given an integer or a list of integer or a boxlist, using ``Vect_boxlist_delete`` C function or the ``Vect_boxlist_delete_boxlist``. :param indx: the index value of the Bbox to remove :param indx: int >>> boxlist = BoxList([Bbox(), ... Bbox(1, 0, 0, 1), ... Bbox(1, -1, -1, 1)]) >>> boxlist.remove(0) >>> boxlist Boxlist([Bbox(1.0, 0.0, 0.0, 1.0), Bbox(1.0, -1.0, -1.0, 1.0)]) """ if hasattr(indx, 'c_boxlist'): libvect.Vect_boxlist_delete_boxlist(self.c_boxlist, indx.c_boxlist) elif isinstance(indx, int): libvect.Vect_boxlist_delete(self.c_boxlist, indx) else: for ind in indx: libvect.Vect_boxlist_delete(self.c_boxlist, ind)
[docs] def reset(self): """Reset the c_boxlist C struct, using the ``Vect_reset_boxlist`` C function. >>> boxlist = BoxList([Bbox(), ... Bbox(1, 0, 0, 1), ... Bbox(1, -1, -1, 1)]) >>> len(boxlist) 3 >>> boxlist.reset() >>> len(boxlist) 0 """ libvect.Vect_reset_boxlist(self.c_boxlist)
[docs]class Ilist(object): """Instantiate a list of integer using the C GRASS struct ``ilist``, the class contains this struct as ``c_ilist`` attribute. """ def __init__(self, integer_list=None): self.c_ilist = ctypes.pointer(libvect.struct_ilist()) if integer_list is not None: self.extend(integer_list) def __getitem__(self, key): if isinstance(key, slice): #import pdb; pdb.set_trace() #Get the start, stop, and step from the slice return [self.c_ilist.contents.value[indx] for indx in range(*key.indices(len(self)))] elif isinstance(key, int): if key < 0: # Handle negative indices key += self.c_ilist.contents.n_values if key >= self.c_ilist.contents.n_values: raise IndexError('Index out of range') return self.c_ilist.contents.value[key] else: raise ValueError("Invalid argument type: %r." % key) def __setitem__(self, key, value): if self.contains(value): raise ValueError('Integer already in the list') self.c_ilist.contents.value[key] = int(value) def __len__(self): return self.c_ilist.contents.n_values def __iter__(self): return (self.c_ilist.contents.value[i] for i in range(self.__len__())) def __repr__(self): return "Ilist(%r)" % [i for i in self.__iter__()] def __contains__(self, item): return item in self.__iter__()
[docs] def append(self, value): """Append an integer to the list""" if libvect.Vect_list_append(self.c_ilist, value): raise # TODO
[docs] def reset(self): """Reset the list""" libvect.Vect_reset_list(self.c_ilist)
[docs] def extend(self, ilist): """Extend the list with another Ilist object or with a list of integers :param ilist: the ilist to append :type ilist: a Ilist object """ if isinstance(ilist, Ilist): libvect.Vect_list_append_list(self.c_ilist, ilist.ilist) else: for i in ilist: self.append(i)
[docs] def remove(self, value): """Remove a value from a list""" if isinstance(value, int): libvect.Vect_list_delete(self.c_ilist, value) elif isinstance(value, Ilist): libvect.Vect_list_delete_list(self.c_ilist, value.ilist) elif isinstance(value, Iterable): for i in value: libvect.Vect_list_delete(self.c_ilist, int(i)) else: raise ValueError('Value: %r, is not supported' % value)
[docs] def contains(self, value): """Check if value is in the list""" return bool(libvect.Vect_val_in_list(self.c_ilist, value))
[docs]class Cats(object): """Instantiate a Category class that contains a ctypes pointer to the C line_cats struct. >>> cats = Cats() >>> for cat in xrange(100, 110): cats.set(cat, layer=cat-50) >>> cats.n_cats 10 >>> [100, 101, 102, 103, 104, 105, 106, 107, 108, 109] >>> cats.layer [50, 51, 52, 53, 54, 55, 56, 57, 58, 59] >>> cats.get() # default layer is 1 (-1, 0) >>> cats.get(50) (100, 1) >>> cats.get(51) (101, 1) >>> cats.set(1001, 52) >>> [100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 1001] >>> cats.layer [50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 52] >>> cats.get(52) (102, 2) >>> cats.reset() >>> cats.layer [] >>> [] """ @property
[docs] def layer(self): field = self.c_cats.contents.field return [field[i] for i in range(self.n_cats)]
[docs] def cat(self): cat = return [cat[i] for i in range(self.n_cats)]
[docs] def n_cats(self): """Return the number of categories""" return self.c_cats.contents.n_cats
def __init__(self, c_cats=None): self.c_cats = c_cats if c_cats else ctypes.pointer(libvect.line_cats())
[docs] def reset(self): """Reset the C cats struct from previous values.""" libvect.Vect_reset_cats(self.c_cats)
[docs] def get(self, layer=1): """Return the first found category of given layer and the number of category found. :param layer: the number of layer :type layer: int """ cat = ctypes.c_int() n_cats = libvect.Vect_cat_get(self.c_cats, layer, ctypes.byref(cat)) return cat.value, n_cats
[docs] def set(self, cat, layer=1): """Add new field/cat to category structure if doesn't exist yet. :param cat: the cat to add :type cat: int :param layer: the number of layer :type layer: int """ libvect.Vect_cat_set(self.c_cats, layer, cat)
[docs] def delete(self, cat=None, layer=1): """If cat is given delete cat from line_cats structure (using Vect_field_cat_del) else delete all categories of given layer (using Vect_cat_del). :param cat: the cat to add :type cat: int :param layer: the number of layer :type layer: int """ if cat: self.n_del = libvect.Vect_field_cat_del(self.c_cats, layer, cat) err_msg = "Layer(%d)/category(%d) number does not exist" err_msg = err_msg % (layer, cat) else: self.n_del = libvect.Vect_cat_del(self.c_cats, layer) err_msg = 'Layer: %r does not exist' % layer if self.n_del == 0: raise ValueError(err_msg)
[docs] def check_cats_constraints(self, cats_list, layer=1): """Check if categories match with category constraints :param cats_list: a list of categories :type cats_list: list :param layer: the number of layer :type layer: int """ return bool(libvect.Vect_cats_in_constraint(self.c_cats, layer, cats_list.c_cat_list))
[docs] def get_list(self, layer=1): """Get list of categories of given field. :param layer: the number of layer :type layer: int """ ilist = Ilist() if libvect.Vect_field_cat_get(self.c_cats, layer, ilist.c_ilist) < 0: raise ValueError('Layer: %r does not exist' % layer) return ilist
[docs]class CatsList(object): """ >>> cats_list = CatsList() >>> cats_list.min [] >>> cats_list.max [] >>> cats_list.n_ranges 0 >>> cats_list.layer 0 >>> string = "2,3,5-9,20" >>> cats_list.from_string(string) >>> cats_list.min [2, 3, 5, 20] >>> cats_list.max [2, 3, 9, 20] >>> cats_list.n_ranges 4 """ @property
[docs] def layer(self): """Return the layer number""" return self.c_cat_list.contents.field
[docs] def n_ranges(self): """Return the ranges number""" return self.c_cat_list.contents.n_ranges
[docs] def min(self): """Return the minimum value""" min_values = self.c_cat_list.contents.min return [min_values[i] for i in range(self.n_ranges)]
[docs] def max(self): """Return the maximum value""" max_values = self.c_cat_list.contents.max return [max_values[i] for i in range(self.n_ranges)]
def __init__(self, c_cat_list=None): self.c_cat_list = c_cat_list if c_cat_list \ else ctypes.pointer(libvect.cat_list())
[docs] def from_string(self, string): """Converts string of categories and cat ranges separated by commas to cat_list. :param string: a string containing the cats separated by commas :type string: str """ num_errors = libvect.Vect_str_to_cat_list(string, self.c_cat_list) if num_errors: from grass.pygrass.errors import GrassError raise GrassError("%d number of errors in ranges" % num_errors)
[docs] def from_array(self, array): """Convert ordered array of integers to cat_list structure. :param array: the input array containing the cats :type array: array """ # Vect_array_to_cat_list(const int *vals, int nvals, ***) # TODO: it's not working libvect.Vect_array_to_cat_list(array, len(array), self.c_cat_list)
def __contains__(self, cat): """Check if category number is in list. :param cat: the category number :type cat: int """ return bool(libvect.Vect_cat_in_cat_list(cat, self.c_cat_list))
if __name__ == "__main__": import doctest doctest.testmod()

Help Index | Topics Index | Keywords Index | Full Index

© 2003-2017 GRASS Development Team, GRASS GIS 7.5.svn Reference Manual