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Source code for pygrass.utils

# -*- coding: utf-8 -*-
import itertools
import fnmatch
import os
from sqlite3 import OperationalError

import grass.lib.gis as libgis
libgis.G_gisinit('')
import grass.lib.raster as libraster
from grass.script import core as grasscore

from grass.pygrass.errors import GrassError


test_vector_name="Utils_test_vector"
test_raster_name="Utils_test_raster"

[docs]def looking(obj, filter_string): """ >>> import grass.lib.vector as libvect >>> sorted(looking(libvect, '*by_box*')) # doctest: +NORMALIZE_WHITESPACE ['Vect_select_areas_by_box', 'Vect_select_isles_by_box', 'Vect_select_lines_by_box', 'Vect_select_nodes_by_box'] """ word_list = dir(obj) word_list.sort() return fnmatch.filter(word_list, filter_string)
[docs]def findfiles(dirpath, match=None): """Return a list of the files""" res = [] for f in sorted(os.listdir(dirpath)): abspath = os.path.join(dirpath, f) if os.path.isdir(abspath): res.extend(findfiles(abspath, match)) if match: if fnmatch.fnmatch(abspath, match): res.append(abspath) else: res.append(abspath) return res
[docs]def findmaps(type, pattern=None, mapset='', location='', gisdbase=''): """Return a list of tuple contining the names of the: * map * mapset, * location, * gisdbase """ from grass.pygrass.gis import Gisdbase, Location, Mapset def find_in_location(type, pattern, location): res = [] for msetname in location.mapsets(): mset = Mapset(msetname, location.name, location.gisdbase) res.extend([(m, mset.name, mset.location, mset.gisdbase) for m in mset.glist(type, pattern)]) return res def find_in_gisdbase(type, pattern, gisdbase): res = [] for loc in gisdbase.locations(): res.extend(find_in_location(type, pattern, Location(loc, gisdbase.name))) return res if gisdbase and location and mapset: mset = Mapset(mapset, location, gisdbase) return [(m, mset.name, mset.location, mset.gisdbase) for m in mset.glist(type, pattern)] elif gisdbase and location: loc = Location(location, gisdbase) return find_in_location(type, pattern, loc) elif gisdbase: gis = Gisdbase(gisdbase) return find_in_gisdbase(type, pattern, gis) elif location: loc = Location(location) return find_in_location(type, pattern, loc) elif mapset: mset = Mapset(mapset) return [(m, mset.name, mset.location, mset.gisdbase) for m in mset.glist(type, pattern)] else: gis = Gisdbase() return find_in_gisdbase(type, pattern, gis)
[docs]def remove(oldname, maptype): """Remove a map""" grasscore.run_command('g.remove', quiet=True, flags='f', type=maptype, name=oldname)
[docs]def rename(oldname, newname, maptype, **kwargs): """Rename a map""" kwargs.update({maptype: '{old},{new}'.format(old=oldname, new=newname), }) grasscore.run_command('g.rename', quiet=True, **kwargs)
[docs]def copy(existingmap, newmap, maptype, **kwargs): """Copy a map >>> copy(test_vector_name, 'mycensus', 'vector') >>> rename('mycensus', 'mynewcensus', 'vector') >>> remove('mynewcensus', 'vector') """ kwargs.update({maptype: '{old},{new}'.format(old=existingmap, new=newmap)}) grasscore.run_command('g.copy', quiet=True, **kwargs)
[docs]def getenv(env): """Return the current grass environment variables >>> from grass.script.core import gisenv >>> getenv("MAPSET") == gisenv()["MAPSET"] True """ return libgis.G_getenv_nofatal(env)
[docs]def get_mapset_raster(mapname, mapset=''): """Return the mapset of the raster map >>> get_mapset_raster(test_raster_name) == getenv("MAPSET") True """ return libgis.G_find_raster2(mapname, mapset)
[docs]def get_mapset_vector(mapname, mapset=''): """Return the mapset of the vector map >>> get_mapset_vector(test_vector_name) == getenv("MAPSET") True """ return libgis.G_find_vector2(mapname, mapset)
[docs]def is_clean_name(name): """Return if the name is valid >>> is_clean_name('census') True >>> is_clean_name('0census') True >>> is_clean_name('census?') True >>> is_clean_name('cénsus') False """ if libgis.G_legal_filename(name) < 0: return False return True
[docs]def coor2pixel(coord, region): """Convert coordinates into a pixel row and col >>> from grass.pygrass.gis.region import Region >>> reg = Region() >>> coor2pixel((reg.west, reg.north), reg) (0.0, 0.0) >>> coor2pixel((reg.east, reg.south), reg) == (reg.rows, reg.cols) True """ (east, north) = coord return (libraster.Rast_northing_to_row(north, region.byref()), libraster.Rast_easting_to_col(east, region.byref()))
[docs]def pixel2coor(pixel, region): """Convert row and col of a pixel into a coordinates >>> from grass.pygrass.gis.region import Region >>> reg = Region() >>> pixel2coor((0, 0), reg) == (reg.north, reg.west) True >>> pixel2coor((reg.cols, reg.rows), reg) == (reg.south, reg.east) True """ (col, row) = pixel return (libraster.Rast_row_to_northing(row, region.byref()), libraster.Rast_col_to_easting(col, region.byref()))
[docs]def get_raster_for_points(poi_vector, raster, column=None, region=None): """Query a raster map for each point feature of a vector Example >>> from grass.pygrass.raster import RasterRow >>> from grass.pygrass.gis.region import Region >>> from grass.pygrass.vector import VectorTopo >>> from grass.pygrass.vector.geometry import Point Create a vector map >>> cols = [(u'cat', 'INTEGER PRIMARY KEY'), ... (u'value', 'double precision')] >>> vect = VectorTopo("test_vect_2") >>> vect.open("w",tab_name="test_vect_2", ... tab_cols=cols) >>> vect.write(Point(10, 6), cat=1, attrs=[10, ]) >>> vect.write(Point(12, 6), cat=2, attrs=[12, ]) >>> vect.write(Point(14, 6), cat=3, attrs=[14, ]) >>> vect.table.conn.commit() >>> vect.close() Setup the raster sampling >>> region = Region() >>> region.from_rast(test_raster_name) >>> region.set_raster_region() >>> ele = RasterRow(test_raster_name) Sample the raster layer at the given points, return a list of values >>> l = get_raster_for_points(vect, ele, region=region) >>> l[0] # doctest: +ELLIPSIS (1, 10.0, 6.0, 1) >>> l[1] # doctest: +ELLIPSIS (2, 12.0, 6.0, 1) Add a new column and sample again >>> vect.open("r") >>> vect.table.columns.add(test_raster_name,'double precision') >>> vect.table.conn.commit() >>> test_raster_name in vect.table.columns True >>> get_raster_for_points(vect, ele, column=test_raster_name, region=region) True >>> vect.table.filters.select('value', test_raster_name) Filters(u'SELECT value, Utils_test_raster FROM test_vect_2;') >>> cur = vect.table.execute() >>> r = cur.fetchall() >>> r[0] # doctest: +ELLIPSIS (10.0, 1.0) >>> r[1] # doctest: +ELLIPSIS (12.0, 1.0) >>> remove('test_vect_2','vect') :param poi_vector: A VectorTopo object that contains points :param raster: raster object :param str column: column name to update in the attrinute table, if set to None a list of sampled values will be returned :param region: The region to work with, if not set the current computational region will be used :return: True in case of success and a specified column for update, if column name for update was not set a list of (id, x, y, value) is returned """ from math import isnan if not column: result = [] if region is None: from grass.pygrass.gis.region import Region region = Region() if not poi_vector.is_open(): poi_vector.open("r") if not raster.is_open(): raster.open("r") if poi_vector.num_primitive_of('point') == 0: raise GrassError(_("Vector doesn't contain points")) for poi in poi_vector.viter('points'): val = raster.get_value(poi, region) if column: if val is not None and not isnan(val): poi.attrs[column] = val else: if val is not None and not isnan(val): result.append((poi.id, poi.x, poi.y, val)) else: result.append((poi.id, poi.x, poi.y, None)) if not column: return result else: poi.attrs.commit() return True
[docs]def r_export(rast, output='', fmt='png', **kargs): from grass.pygrass.modules import Module if rast.exist(): output = output if output else "%s_%s.%s" % (rast.name, rast.mapset, fmt) Module('r.out.%s' % fmt, input=rast.fullname(), output=output, overwrite=True, **kargs) return output else: raise ValueError('Raster map does not exist.')
[docs]def get_lib_path(modname, libname=None): """Return the path of the libname contained in the module. .. deprecated:: 7.1 Use :func:`grass.script.utils.get_lib_path` instead. """ from grass.script.utils import get_lib_path return get_lib_path(modname=modname, libname=libname)
[docs]def set_path(modulename, dirname=None, path='.'): """Set sys.path looking in the the local directory GRASS directories. :param modulename: string with the name of the GRASS module :param dirname: string with the directory name containing the python libraries, default None :param path: string with the path to reach the dirname locally. .. deprecated:: 7.1 Use :func:`grass.script.utils.set_path` instead. """ from grass.script.utils import set_path return set_path(modulename=modulename, dirname=dirname, path=path)
[docs]def split_in_chunk(iterable, length=10): """Split a list in chunk. >>> for chunk in split_in_chunk(range(25)): print chunk (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) (10, 11, 12, 13, 14, 15, 16, 17, 18, 19) (20, 21, 22, 23, 24) >>> for chunk in split_in_chunk(range(25), 3): print chunk (0, 1, 2) (3, 4, 5) (6, 7, 8) (9, 10, 11) (12, 13, 14) (15, 16, 17) (18, 19, 20) (21, 22, 23) (24,) """ it = iter(iterable) while True: chunk = tuple(itertools.islice(it, length)) if not chunk: return yield chunk
[docs]def table_exist(cursor, table_name): """Return True if the table exist False otherwise""" try: # sqlite cursor.execute("SELECT name FROM sqlite_master" " WHERE type='table' AND name='%s';" % table_name) except OperationalError: try: # pg cursor.execute("SELECT EXISTS(SELECT * FROM " "information_schema.tables " "WHERE table_name=%s)" % table_name) except OperationalError: return False one = cursor.fetchone() if cursor else None return True if one and one[0] else False
[docs]def create_test_vector_map(map_name="test_vector"): """This functions creates a vector map layer with points, lines, boundaries, centroids, areas, isles and attributes for testing purposes This should be used in doc and unit tests to create location/mapset independent vector map layer. This map includes 3 points, 3 lines, 11 boundaries and 4 centroids. The attribute table contains cat, name and value columns. param map_name: The vector map name that should be used P1 P2 P3 6 * * * 5 4 _______ ___ ___ L1 L2 L3 Y 3 |A1___ *| *| *| | | | 2 | |A2*| | | | | | | 1 | |___| |A3 |A4 | | | | 0 |_______|___|___| | | | -1 -1 0 1 2 3 4 5 6 7 8 9 10 12 14 X """ from grass.pygrass.vector import VectorTopo from grass.pygrass.vector.geometry import Point, Line, Centroid, Boundary cols = [(u'cat', 'INTEGER PRIMARY KEY'), (u'name','varchar(50)'), (u'value', 'double precision')] with VectorTopo(map_name, mode='w', tab_name=map_name, tab_cols=cols) as vect: # Write 3 points vect.write(Point(10, 6), cat=1, attrs=("point", 1)) vect.write(Point(12, 6), cat=1) vect.write(Point(14, 6), cat=1) # Write 3 lines vect.write(Line([(10, 4), (10, 2), (10,0)]), cat=2, attrs=("line", 2)) vect.write(Line([(12, 4), (12, 2), (12,0)]), cat=2) vect.write(Line([(14, 4), (14, 2), (14,0)]), cat=2) # boundaries 1 - 4 vect.write(Boundary(points=[(0, 0), (0,4)])) vect.write(Boundary(points=[(0, 4), (4,4)])) vect.write(Boundary(points=[(4, 4), (4,0)])) vect.write(Boundary(points=[(4, 0), (0,0)])) # 5. boundary (Isle) vect.write(Boundary(points=[(1, 1), (1,3), (3, 3), (3,1), (1,1)])) # boundaries 6 - 8 vect.write(Boundary(points=[(4, 4), (6,4)])) vect.write(Boundary(points=[(6, 4), (6,0)])) vect.write(Boundary(points=[(6, 0), (4,0)])) # boundaries 9 - 11 vect.write(Boundary(points=[(6, 4), (8,4)])) vect.write(Boundary(points=[(8, 4), (8,0)])) vect.write(Boundary(points=[(8, 0), (6,0)])) # Centroids, all have the same cat and attribute vect.write(Centroid(x=3.5, y=3.5), cat=3, attrs=("centroid", 3)) vect.write(Centroid(x=2.5, y=2.5), cat=3) vect.write(Centroid(x=5.5, y=3.5), cat=3) vect.write(Centroid(x=7.5, y=3.5), cat=3) vect.organization = 'Thuenen Institut' vect.person = 'Soeren Gebbert' vect.title = 'Test dataset' vect.comment = 'This is a comment' vect.table.conn.commit() vect.organization = "Thuenen Institut" vect.person = "Soeren Gebbert" vect.title = "Test dataset" vect.comment = "This is a comment" vect.close()
[docs]def create_test_stream_network_map(map_name="streams"): """ This functions creates a vector map layer with lines that represent a stream network with two different graphs. The first graph contains a loop, the second can be used as directed graph. This should be used in doc and unit tests to create location/mapset independent vector map layer. param map_name: The vector map name that should be used 1(0,2) 3(2,2) \ / 1 \ / 2 \ / 2(1,1) 6(0,1) || 5(2,1) 5 \ || / 4 \||/ 4(1,0) | | 6 |7(1,-1) 7(0,-1) 8(2,-1) \ / 8 \ / 9 \ / 9(1, -2) | | 10 | 10(1,-3) """ from grass.pygrass.vector import VectorTopo from grass.pygrass.vector.geometry import Line cols = [(u'cat', 'INTEGER PRIMARY KEY'), (u'id', 'INTEGER')] with VectorTopo(map_name, mode='w', tab_name=map_name, tab_cols=cols) as streams: # First flow graph l = Line([(0,2), (0.22, 1.75), (0.55, 1.5), (1,1)]) streams.write(l, cat=1, attrs=(1,)) l = Line([(2,2),(1,1)]) streams.write(l, cat=2, attrs=(2,)) l = Line([(1,1), (0.85, 0.5), (1,0)]) streams.write(l, cat=3, attrs=(3,)) l = Line([(2,1),(1,0)]) streams.write(l, cat=4, attrs=(4,)) l = Line([(0,1),(1,0)]) streams.write(l, cat=5, attrs=(5,)) l = Line([(1,0),(1,-1)]) streams.write(l, cat=6, attrs=(6,)) # Reverse line 3 l = Line([(1,0), (1.15, 0.5),(1,1)]) streams.write(l, cat=7, attrs=(7,)) # second flow graph l = Line([(0,-1),(1,-2)]) streams.write(l, cat=8, attrs=(8,)) l = Line([(2,-1),(1,-2)]) streams.write(l, cat=9, attrs=(9,)) l = Line([(1,-2),(1,-3)]) streams.write(l, cat=10, attrs=(10,)) streams.organization = 'Thuenen Institut' streams.person = 'Soeren Gebbert' streams.title = 'Test dataset for stream networks' streams.comment = 'This is a comment' streams.table.conn.commit() streams.close()
if __name__ == "__main__": import doctest from grass.pygrass import utils from grass.script.core import run_command utils.create_test_vector_map(test_vector_name) run_command("g.region", n=50, s=0, e=60, w=0, res=1) run_command("r.mapcalc", expression="%s = 1"%(test_raster_name), overwrite=True) doctest.testmod() """Remove the generated vector map, if exist""" mset = utils.get_mapset_vector(test_vector_name, mapset='') if mset: run_command("g.remove", flags='f', type='vector', name=test_vector_name) mset = utils.get_mapset_raster(test_raster_name, mapset='') if mset: run_command("g.remove", flags='f', type='raster', name=test_raster_name)

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