Source code for pygrass.modules.grid.patch

# -*- coding: utf-8 -*-
"""
Created on Tue Apr  2 18:57:42 2013

@author: pietro
"""
from __future__ import (nested_scopes, generators, division, absolute_import,
                        with_statement, print_function, unicode_literals)
from grass.pygrass.gis.region import Region
from grass.pygrass.raster import RasterRow
from grass.pygrass.utils import coor2pixel


[docs]def get_start_end_index(bbox_list): """Convert a Bounding Box to a list of the index of column start, end, row start and end :param bbox_list: a list of BBox object to convert :type bbox_list: list of BBox object """ ss_list = [] reg = Region() for bbox in bbox_list: r_start, c_start = coor2pixel((bbox.west, bbox.north), reg) r_end, c_end = coor2pixel((bbox.east, bbox.south), reg) ss_list.append((int(r_start), int(r_end), int(c_start), int(c_end))) return ss_list
[docs]def rpatch_row(rast, rasts, bboxes): """Patch a row of bound boxes. :param rast: a Raster object to write :type rast: Raster object :param rasts: a list of Raster object to read :type rasts: list of Raster object :param bboxes: a list of BBox object :type bboxes: list of BBox object """ sei = get_start_end_index(bboxes) # instantiate two buffer buff = rasts[0][0] rbuff = rasts[0][0] r_start, r_end, c_start, c_end = sei[0] for row in range(r_start, r_end): for col, ras in enumerate(rasts): r_start, r_end, c_start, c_end = sei[col] buff = ras.get_row(row, buff) rbuff[c_start:c_end] = buff[c_start:c_end] rast.put_row(rbuff)
[docs]def rpatch_map(raster, mapset, mset_str, bbox_list, overwrite=False, start_row=0, start_col=0, prefix=''): # TODO is prefix useful?? """Patch raster using a bounding box list to trim the raster. :param raster: the name of output raster :type raster: str :param mapset: the name of mapset to use :type mapset: str :param mset_str: :type mset_str: str :param bbox_list: a list of BBox object to convert :type bbox_list: list of BBox object :param overwrite: overwrite existing raster :type overwrite: bool :param start_row: the starting row of original raster :type start_row: int :param start_col: the starting column of original raster :type start_col: int :param prefix: the prefix of output raster :type prefix: str """ # Instantiate the RasterRow input objects rast = RasterRow(prefix + raster, mapset) rtype = RasterRow(name=raster, mapset=mset_str % (0, 0)) rtype.open('r') rast.open('w', mtype=rtype.mtype, overwrite=overwrite) rtype.close() rasts = [] for row, rbbox in enumerate(bbox_list): rrasts = [] for col in range(len(rbbox)): rrasts.append(RasterRow(name=raster, mapset=mset_str % (start_row + row, start_col + col))) rrasts[-1].open('r') rasts.append(rrasts) rpatch_row(rast, rrasts, rbbox) for rst in rrasts: rst.close() del(rst) rast.close()