"""
Functions to use GRASS 2D and 3D rasters with NumPy.
Usage:
>>> from __future__ import print_function
>>> import grass.script as gscript
>>> from grass.script import array as garray
>>>
>>> # We create a temporary region that is only valid in this python session
... gscript.use_temp_region()
>>> gscript.run_command("g.region", n=80, e=120, t=60, s=0, w=0, b=0, res=20, res3=20)
0
>>>
>>> # Lets create a raster map numpy array
... # based at the current region settings
... map2d_1 = garray.array()
>>>
>>> # Write some data
... for y in range(map2d_1.shape[0]):
... for x in range(map2d_1.shape[1]):
... map2d_1[y,x] = y + x
...
>>> # Lets have a look at the array
... print(map2d_1)
[[ 0. 1. 2. 3. 4. 5.]
[ 1. 2. 3. 4. 5. 6.]
[ 2. 3. 4. 5. 6. 7.]
[ 3. 4. 5. 6. 7. 8.]]
>>> # This will write the numpy array as GRASS raster map
... # with name map2d_1
... map2d_1.write(mapname="map2d_1", overwrite=True)
0
>>>
>>> # We create a new array from raster map2d_1 to modify it
... map2d_2 = garray.array(mapname="map2d_1")
>>> # Don't do map2d_2 = map2d_1 % 3
... # because: this will overwrite the internal temporary filename
... map2d_2 %= 3
>>> # Show the result
... print(map2d_2)
[[ 0. 1. 2. 0. 1. 2.]
[ 1. 2. 0. 1. 2. 0.]
[ 2. 0. 1. 2. 0. 1.]
[ 0. 1. 2. 0. 1. 2.]]
>>> # Write the result as new raster map with name map2d_2
... map2d_2.write(mapname="map2d_2", overwrite=True)
0
>>>
>>> # Here we create a 3D raster map numpy array
... # based in the current region settings
... map3d_1 = garray.array3d()
>>>
>>> # Write some data
... # Note: the 3D array has map[depth][row][column] order
... for z in range(map3d_1.shape[0]):
... for y in range(map3d_1.shape[1]):
... for x in range(map3d_1.shape[2]):
... map3d_1[z,y,x] = z + y + x
...
>>> # Lets have a look at the 3D array
... print(map3d_1)
[[[ 0. 1. 2. 3. 4. 5.]
[ 1. 2. 3. 4. 5. 6.]
[ 2. 3. 4. 5. 6. 7.]
[ 3. 4. 5. 6. 7. 8.]]
<BLANKLINE>
[[ 1. 2. 3. 4. 5. 6.]
[ 2. 3. 4. 5. 6. 7.]
[ 3. 4. 5. 6. 7. 8.]
[ 4. 5. 6. 7. 8. 9.]]
<BLANKLINE>
[[ 2. 3. 4. 5. 6. 7.]
[ 3. 4. 5. 6. 7. 8.]
[ 4. 5. 6. 7. 8. 9.]
[ 5. 6. 7. 8. 9. 10.]]]
>>> # This will write the numpy array as GRASS 3D raster map
... # with name map3d_1
... map3d_1.write(mapname="map3d_1", overwrite=True)
0
>>> # We create a new 3D array from 3D raster map3d_1 to modify it
... map3d_2 = garray.array3d(mapname="map3d_1")
>>> # Don't do map3d_2 = map3d_1 % 3
... # because: this will overwrite the internal temporary filename
... map3d_2 %= 3
>>> # Show the result
... print(map3d_2)
[[[ 0. 1. 2. 0. 1. 2.]
[ 1. 2. 0. 1. 2. 0.]
[ 2. 0. 1. 2. 0. 1.]
[ 0. 1. 2. 0. 1. 2.]]
<BLANKLINE>
[[ 1. 2. 0. 1. 2. 0.]
[ 2. 0. 1. 2. 0. 1.]
[ 0. 1. 2. 0. 1. 2.]
[ 1. 2. 0. 1. 2. 0.]]
<BLANKLINE>
[[ 2. 0. 1. 2. 0. 1.]
[ 0. 1. 2. 0. 1. 2.]
[ 1. 2. 0. 1. 2. 0.]
[ 2. 0. 1. 2. 0. 1.]]]
>>> # Write the result as new 3D raster map with name map3d_2
... map3d_2.write(mapname="map3d_2", overwrite=True)
0
(C) 2010-2012 by Glynn Clements and the GRASS Development Team
This program is free software under the GNU General Public
License (>=v2). Read the file COPYING that comes with GRASS
for details.
.. sectionauthor:: Glynn Clements
"""
from __future__ import absolute_import
import sys
import numpy
from .utils import try_remove
from . import core as gcore
from grass.exceptions import CalledModuleError
###############################################################################
class _tempfile(object):
def __init__(self):
self.filename = gcore.tempfile()
def __del__(self):
try_remove(self.filename)
###############################################################################
[docs]class array(numpy.memmap):
def __new__(cls, mapname=None, null=None, dtype=numpy.double):
"""Define new numpy array
:param cls:
:param dtype: data type (default: numpy.double)
"""
reg = gcore.region()
r = reg['rows']
c = reg['cols']
shape = (r, c)
tempfile = _tempfile()
if mapname:
kind = numpy.dtype(dtype).kind
size = numpy.dtype(dtype).itemsize
if kind == 'f':
flags = 'f'
elif kind in 'biu':
flags = 'i'
else:
raise ValueError(_('Invalid kind <%s>') % kind)
if size not in [1, 2, 4, 8]:
raise ValueError(_('Invalid size <%d>') % size)
gcore.run_command(
'r.out.bin',
flags=flags,
input=mapname,
output=tempfile.filename,
bytes=size,
null=null,
quiet=True,
overwrite=True)
self = numpy.memmap.__new__(
cls,
filename=tempfile.filename,
dtype=dtype,
mode='r+',
shape=shape)
self.tempfile = tempfile
self.filename = tempfile.filename
return self
[docs] def read(self, mapname, null=None):
"""Read raster map into array
:param str mapname: name of raster map to be read
:param null: null value
:return: 0 on success
:return: non-zero code on failure
.. deprecated:: 7.1
Instead reading the map after creating the array,
pass the map name in the array constructor.
"""
if sys.platform == 'win32':
gcore.warning(_("grass.script.array.read is deprecated and does not"
" work on MS Windows, pass raster name in the constructor"))
kind = self.dtype.kind
size = self.dtype.itemsize
if kind == 'f':
flags = 'f'
elif kind in 'biu':
flags = 'i'
else:
raise ValueError(_('Invalid kind <%s>') % kind)
if size not in [1, 2, 4, 8]:
raise ValueError(_('Invalid size <%d>') % size)
try:
gcore.run_command(
'r.out.bin',
flags=flags,
input=mapname,
output=self.filename,
bytes=size,
null=null,
quiet=True,
overwrite=True)
except CalledModuleError:
return 1
else:
return 0
[docs] def write(self, mapname, title=None, null=None, overwrite=None):
"""Write array into raster map
:param str mapname: name for raster map
:param str title: title for raster map
:param null: null value
:param bool overwrite: True for overwritting existing raster maps
:return: 0 on success
:return: non-zero code on failure
"""
kind = self.dtype.kind
size = self.dtype.itemsize
if kind == 'f':
if size == 4:
flags = 'f'
elif size == 8:
flags = 'd'
else:
raise ValueError(_('Invalid FP size <%d>') % size)
size = None
elif kind in 'biu':
if size not in [1, 2, 4]:
raise ValueError(_('Invalid integer size <%d>') % size)
flags = None
else:
raise ValueError(_('Invalid kind <%s>') % kind)
reg = gcore.region()
try:
gcore.run_command(
'r.in.bin',
flags=flags,
input=self.filename,
output=mapname,
title=title,
bytes=size,
anull=null,
overwrite=overwrite,
north=reg['n'],
south=reg['s'],
east=reg['e'],
west=reg['w'],
rows=reg['rows'],
cols=reg['cols'])
except CalledModuleError:
return 1
else:
return 0
###############################################################################
[docs]class array3d(numpy.memmap):
def __new__(cls, mapname=None, null=None, dtype=numpy.double):
"""Define new 3d numpy array
:param cls:
:param dtype: data type (default: numpy.double)
"""
reg = gcore.region(True)
r = reg['rows3']
c = reg['cols3']
d = reg['depths']
shape = (d, r, c)
tempfile = _tempfile()
if mapname:
kind = numpy.dtype(dtype).kind
size = numpy.dtype(dtype).itemsize
if kind == 'f':
flags = None # default is double
elif kind in 'biu':
flags = 'i'
else:
raise ValueError(_('Invalid kind <%s>') % kind)
if size not in [1, 2, 4, 8]:
raise ValueError(_('Invalid size <%d>') % size)
gcore.run_command(
'r3.out.bin',
flags=flags,
input=mapname,
output=tempfile.filename,
bytes=size,
null=null,
quiet=True,
overwrite=True)
self = numpy.memmap.__new__(
cls,
filename=tempfile.filename,
dtype=dtype,
mode='r+',
shape=shape)
self.tempfile = tempfile
self.filename = tempfile.filename
return self
[docs] def read(self, mapname, null=None):
"""Read 3D raster map into array
:param str mapname: name of 3D raster map to be read
:param null: null value
:return: 0 on success
:return: non-zero code on failure
.. deprecated:: 7.1
Instead reading the map after creating the array,
pass the map name in the array constructor.
"""
if sys.platform == 'win32':
gcore.warning(_("grass.script.array3d.read is deprecated and does not"
" work on MS Windows, pass 3D raster name in the constructor"))
kind = self.dtype.kind
size = self.dtype.itemsize
if kind == 'f':
flags = None # default is double
elif kind in 'biu':
flags = 'i'
else:
raise ValueError(_('Invalid kind <%s>') % kind)
if size not in [1, 2, 4, 8]:
raise ValueError(_('Invalid size <%d>') % size)
try:
gcore.run_command(
'r3.out.bin',
flags=flags,
input=mapname,
output=self.filename,
bytes=size,
null=null,
quiet=True,
overwrite=True)
except CalledModuleError:
return 1
else:
return 0
[docs] def write(self, mapname, null=None, overwrite=None):
"""Write array into 3D raster map
:param str mapname: name for 3D raster map
:param null: null value
:param bool overwrite: True for overwriting existing raster maps
:return: 0 on success
:return: non-zero code on failure
"""
kind = self.dtype.kind
size = self.dtype.itemsize
flags = None
if kind == 'f':
if size != 4 and size != 8:
raise ValueError(_('Invalid FP size <%d>') % size)
elif kind in 'biu':
if size not in [1, 2, 4, 8]:
raise ValueError(_('Invalid integer size <%d>') % size)
flags = 'i'
else:
raise ValueError(_('Invalid kind <%s>') % kind)
reg = gcore.region(True)
try:
gcore.run_command(
'r3.in.bin',
flags=flags,
input=self.filename,
output=mapname,
bytes=size,
null=null,
overwrite=overwrite,
north=reg['n'],
south=reg['s'],
top=reg['t'],
bottom=reg['b'],
east=reg['e'],
west=reg['w'],
depths=reg['depths'],
rows=reg['rows3'],
cols=reg['cols3'])
except CalledModuleError:
return 1
else:
return 0
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