本文整理汇总了Python中qgis.core.QgsRasterLayer.rasterUnitsPerPixelX方法的典型用法代码示例。如果您正苦于以下问题:Python QgsRasterLayer.rasterUnitsPerPixelX方法的具体用法?Python QgsRasterLayer.rasterUnitsPerPixelX怎么用?Python QgsRasterLayer.rasterUnitsPerPixelX使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类qgis.core.QgsRasterLayer
的用法示例。
在下文中一共展示了QgsRasterLayer.rasterUnitsPerPixelX方法的5个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: test_clipRaster
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import rasterUnitsPerPixelX [as 别名]
def test_clipRaster(self):
"""Raster layers can be clipped
"""
# Create a raster layer
myName = 'shake'
myRasterLayer = QgsRasterLayer(RASTERPATH, myName)
myMessage = 'Did not find layer "%s" in path "%s"' % \
(myName, RASTERPATH)
assert myRasterLayer is not None, myMessage
# Create a bounding box
myRect = [97, -3, 104, 1]
# Clip the vector to the bbox
myResult = clip_layer(myRasterLayer, myRect)
# Check the output is valid
assert os.path.exists(myResult.source())
# Clip and give a desired resolution for the output
mySize = 0.05
myResult = clip_layer(myRasterLayer, myRect, mySize)
myNewRasterLayer = QgsRasterLayer(myResult.source(), myName)
assert myNewRasterLayer.isValid(), 'Resampled raster is not valid'
myMessage = ('Resampled raster has incorrect pixel size.'
'Expected: %f, Actual: %f' %
(mySize, myNewRasterLayer.rasterUnitsPerPixelX()))
assert myNewRasterLayer.rasterUnitsPerPixelX() == mySize, myMessage
示例2: test_clip_raster
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import rasterUnitsPerPixelX [as 别名]
def test_clip_raster(self):
"""Raster layers can be clipped."""
# Create a raster layer
layer_name = 'shake'
raster_layer = QgsRasterLayer(RASTERPATH, layer_name)
message = (
'Did not find layer "%s" in path "%s"' % (layer_name, RASTERPATH))
assert raster_layer is not None, message
# Create a bounding box
bounding_box = [97, -3, 104, 1]
# Clip the vector to the bbox
result = clip_layer(raster_layer, bounding_box)
# Check the output is valid
assert os.path.exists(result.source())
# Clip and give a desired resolution for the output
# big pixel size
size = 0.05
result = clip_layer(raster_layer, bounding_box, size)
new_raster_layer = QgsRasterLayer(result.source(), layer_name)
assert new_raster_layer.isValid(), 'Resampled raster is not valid'
message = (
'Resampled raster has incorrect pixel size. Expected: %5f, '
'Actual: %5f' % (size, new_raster_layer.rasterUnitsPerPixelX()))
assert new_raster_layer.rasterUnitsPerPixelX() == size, message
示例3: test_clip_raster_small
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import rasterUnitsPerPixelX [as 别名]
def test_clip_raster_small(self):
"""Raster layers can be clipped in small and precise size. For #710."""
# Create a raster layer
layer_name = 'shake'
raster_layer = QgsRasterLayer(RASTERPATH, layer_name)
message = (
'Did not find layer "%s" in path "%s"' % (layer_name, RASTERPATH))
assert raster_layer is not None, message
# Create a bounding box
bounding_box = [97, -3, 104, 1]
# Clip the vector to the bbox
result = clip_layer(raster_layer, bounding_box)
# Check the output is valid
assert os.path.exists(result.source())
# Clip and give a desired resolution for the output
# small pixel size and high precision
# based on pixel size of Flood_Current_Depth_Jakarta_geographic.asc
size = 0.00045228819716
result = clip_layer(raster_layer, bounding_box, size)
new_raster_layer = QgsRasterLayer(result.source(), layer_name)
assert new_raster_layer.isValid(), 'Resampled raster is not valid'
message = (
'Resampled raster has incorrect pixel size. Expected: %.14f, '
'Actual: %.14f' % (
size, new_raster_layer.rasterUnitsPerPixelX()))
result_size = new_raster_layer.rasterUnitsPerPixelX()
self.assertAlmostEqual(result_size, size, places=13, msg=message)
示例4: TestQGISRasterTools
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import rasterUnitsPerPixelX [as 别名]
class TestQGISRasterTools(unittest.TestCase):
def setUp(self):
self.raster = QgsRasterLayer(RASTER_BASE + '.tif', 'test')
self.provider = self.raster.dataProvider()
self.extent = self.raster.extent()
self.x_res = self.raster.rasterUnitsPerPixelX()
self.y_res = self.raster.rasterUnitsPerPixelY()
def test_pixels_to_points(self):
points = pixels_to_points(
self.raster, threshold_min=1.0, threshold_max=1.5)
# There are four such pixels only
self.assertEquals(points.featureCount(), 4)
for point in points.dataProvider().getFeatures():
point = point.geometry().asPoint()
# Move point in center of the pixels and get the value
value = self.provider.identify(
QgsPoint(
point.x() + 0.5 * self.x_res,
point.y() - 0.5 * self.y_res),
QgsRaster.IdentifyFormatValue,
self.extent)
value = value.results()[1]
self.assertGreater(value, 1.0)
self.assertLess(value, 1.5)
# Infinite threshold test
points = pixels_to_points(self.raster, threshold_min=1.1)
self.assertEquals(points.featureCount(), 8)
for point in points.dataProvider().getFeatures():
point = point.geometry().asPoint()
# Move point in center of the pixels and get the value
value = self.provider.identify(
QgsPoint(
point.x() + 0.5 * self.x_res,
point.y() - 0.5 * self.y_res),
QgsRaster.IdentifyFormatValue,
self.extent)
value = value.results()[1]
self.assertGreater(value, 1.1)
test_pixels_to_points.slow = True
def test_polygonize(self):
"""Test if polygonize works"""
geometry = polygonize(
self.raster, threshold_min=1.0, threshold_max=1.5)
# Result is one square
self.assertTrue(geometry.isGeosValid())
self.assertFalse(geometry.isMultipart())
# noinspection PyArgumentEqualDefault
geometry = polygonize(self.raster, threshold_min=0.0)
# Result is several polygons
self.assertTrue(geometry.isGeosValid())
self.assertTrue(geometry.isMultipart())
expected = QgsVectorLayer(VECTOR_BASE + '.shp', 'test', 'ogr')
for feature in expected.getFeatures():
# the layer has one feature only
expected_geom = feature.geometry()
self.assertTrue((geometry.isGeosEqual(expected_geom)))
test_polygonize.slow = True
def test_clip_raster(self):
"""Test clip_raster work"""
new_raster = clip_raster(
self.raster,
self.raster.width(),
self.raster.height(),
self.extent
)
self.assertEqual(self.raster.rasterUnitsPerPixelY(),
new_raster.rasterUnitsPerPixelY())
self.assertEqual(self.raster.rasterUnitsPerPixelX(),
new_raster.rasterUnitsPerPixelX())
self.assertEqual(self.raster.extent(),
new_raster.extent())
self.assertEqual(self.raster.width(),
new_raster.width())
self.assertEqual(self.raster.height(),
new_raster.height())
# Set extent as 1/2 of self.extent
center = self.extent.center()
x_max, y_max = center.x(), center.y()
new_extent = QgsRectangle(
self.extent.xMinimum(),
self.extent.yMinimum(),
x_max,
y_max
)
new_raster = clip_raster(
self.raster,
self.raster.width(),
self.raster.height(),
#.........这里部分代码省略.........
示例5: run
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import rasterUnitsPerPixelX [as 别名]
def run(self):
"""Run method that performs all the real work"""
# show the dialog
self.dlg.show()
# Run the dialog event loop
result = self.dlg.exec_()
# See if OK was pressed
if result:
# Do something useful here - delete the line containing pass and
# substitute with your code.
"""read path from user input"""
inputPath = self.dlg.Path.text()
"""set path for output file and concat file name to path"""
outputPath = 'C:\Users\Administrator\Desktop\\'
outputName = self.dlg.fileName.text()
outputFile = outputPath + outputName
"""read image and calculate electrical conductivity and electrical Resistivity and set RGB for each pixel which R represent adj Pred Moist,
G represents electrical conductivity and B represents electrical resistivity"""
"""for tiff file output"""
if(self.dlg.tiff.isChecked()):
oldImage = Image.open(inputPath)
rgb_image = oldImage.convert('RGB')
newImage = Image.new(oldImage.mode,oldImage.size,'white')
for x in xrange(newImage.size[0]):
for y in xrange(newImage.size[1]):
R, G, B = rgb_image.getpixel((x, y))
sand = (R * 0.4 / 255.0)
clay = (G * 0.5 / 255.0)
om = (B * 5 / 255.0)
predMoist = -0.251 * sand + 0.195 * clay + 0.011 * om + 0.006 * sand * om - 0.027 * clay * om + 0.452 * sand * clay + 0.299
adjPredMoist = predMoist + (1.283 * predMoist * predMoist - 0.374 * predMoist - 0.015)
electricalConductivity = 0.000471052 * math.pow(100 * adjPredMoist, 3.458)
electricalResistivity = 1000.0 / electricalConductivity
newImage.putpixel((x,y),(int(adjPredMoist), int(electricalConductivity), int(electricalResistivity)))
newImage.save(outputFile + '.tif')
"""create raster layer and calculate electrical conductivity and write in ASCII XYZ file which X and Y represent centroid coordinate of each pixel
and Z represents electrical conductivity"""
"""for ASCII XYZ file output"""
if(self.dlg.asciiXYZ.isChecked()):
raster = QgsRasterLayer(inputPath)
w = raster.width()
h = raster.height()
p = raster.dataProvider()
b = p.block(0, p.extent(), w, h)
f = file(outputFile + '.xyz', 'w')
f.write('X,Y,Z(Electrical Conductivity)\n')
pix_x = raster.rasterUnitsPerPixelX()
pix_y = raster.rasterUnitsPerPixelY()
half_x = pix_x / 2
half_y = pix_y / 2
extent = p.extent()
count = 0
y = extent.yMinimum()
while y < extent.yMaximum():
y += pix_y
count += 1
x = extent.xMinimum()
while x < extent.xMaximum():
x += pix_x
pos = QgsPoint(x - half_x, y - half_y)
R = p.identify(pos, QgsRaster.IdentifyFormatValue).results()[1]
G = p.identify(pos, QgsRaster.IdentifyFormatValue).results()[2]
B = p.identify(pos, QgsRaster.IdentifyFormatValue).results()[3]
sand = (R * 0.4 / 255.0)
clay = (G * 0.5 / 255.0)
om = (B * 5 / 255.0)
predMoist = -0.251 * sand + 0.195 * clay + 0.011 * om + 0.006 * sand * om - 0.027 * clay * om + 0.452 * sand * clay + 0.299
adjPredMoist = predMoist + (1.283 * predMoist * predMoist - 0.374 * predMoist - 0.015)
electricalConductivity = 0.000471052 * math.pow(100 * adjPredMoist, 3.458)
f.write('%s, %s, %s\n' % (pos.x(),pos.y(), electricalConductivity))
f.close()