本文整理汇总了Python中sextante.algs.ftools.FToolsUtils.extractPoints方法的典型用法代码示例。如果您正苦于以下问题：Python FToolsUtils.extractPoints方法的具体用法？Python FToolsUtils.extractPoints怎么用？Python FToolsUtils.extractPoints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sextante.algs.ftools.FToolsUtils的用法示例。
在下文中一共展示了FToolsUtils.extractPoints方法的4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: processAlgorithm
# 需要导入模块: from sextante.algs.ftools import FToolsUtils [as 别名]
# 或者: from sextante.algs.ftools.FToolsUtils import extractPoints [as 别名]
def processAlgorithm(self, progress):
layer = QGisLayers.getObjectFromUri(self.getParameterValue(self.POINTS))
weightField = self.getParameterValue(self.WEIGHT)
uniqueField = self.getParameterValue(self.UID)
weightIndex = layer.fieldNameIndex(weightField)
uniqueIndex = layer.fieldNameIndex(uniqueField)
fieldList = [QgsField("MEAN_X", QVariant.Double, "", 24, 15),
QgsField("MEAN_Y", QVariant.Double, "", 24, 15),
QgsField("UID", QVariant.String, "", 255)
]
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fieldList,
QGis.WKBPoint, layer.crs())
current = 0
features = QGisLayers.features(layer)
total = 100.0 / float(len(features))
means = {}
for feat in features:
current += 1
progress.setPercentage(current * total)
clazz = str(feat.attributes()[uniqueIndex]).strip()
if weightIndex == -1:
weight = 1.00
else:
try:
weight = float(feat.attributes()[weightIndex])
except:
weight = 1.00
if clazz not in means:
means[clazz] = (0,0,0)
cx,cy, totalweight = means[clazz]
geom = QgsGeometry(feat.geometry())
geom = utils.extractPoints(geom)
for i in geom:
cx += i.x() * weight
cy += i.y() * weight
totalweight += weight
means[clazz] = (cx, cy, totalweight)
for clazz, values in means.iteritems():
outFeat = QgsFeature()
cx = values[0] / values[2]
cy = values[1] / values[2]
meanPoint = QgsPoint(cx, cy)
outFeat.setGeometry(QgsGeometry.fromPoint(meanPoint))
outFeat.setAttributes([cx, cy, clazz])
writer.addFeature(outFeat)
del writer示例2: processAlgorithm
# 需要导入模块: from sextante.algs.ftools import FToolsUtils [as 别名]
# 或者: from sextante.algs.ftools.FToolsUtils import extractPoints [as 别名]
def processAlgorithm(self, progress):
layer = QGisLayers.getObjectFromUri(self.getParameterValue(self.POINTS))
weightField = self.getParameterValue(self.WEIGHT)
uniqueField = self.getParameterValue(self.UID)
provider = layer.dataProvider()
weightIndex = layer.fieldNameIndex(weightField)
uniqueIndex = layer.fieldNameIndex(uniqueField)
if uniqueIndex <> -1:
uniqueValues = utils.getUniqueValues(layer, uniqueIndex)
single = False
else:
uniqueValues = [QVariant(1)]
single = True
fieldList = [QgsField("MEAN_X", QVariant.Double, "", 24, 15),
QgsField("MEAN_Y", QVariant.Double, "", 24, 15),
QgsField("UID", QVariant.String, "", 255)
]
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fieldList,
QGis.WKBPoint, layer.crs())
current = 0
total = 100.0 / float(provider.featureCount() * len(uniqueValues))
outFeat = QgsFeature()
for j in uniqueValues:
cx = 0.00
cy = 0.00
points = []
weights = []
features = QGisLayers.features(layer)
for feat in features:
current += 1
progress.setPercentage(current * total)
if single:
check = j.toString().trimmed()
else:
check = feat.attributes()[uniqueIndex].toString().trimmed()
if check == j.toString().trimmed():
cx = 0.00
cy = 0.00
if weightIndex == -1:
weight = 1.00
else:
try:
weight = float(feat.attributes()[weightIndex].toDouble()[0])
except:
weight = 1.00
geom = QgsGeometry(feat.geometry())
geom = utils.extractPoints(geom)
for i in geom:
cx += i.x()
cy += i.y()
points.append(QgsPoint((cx / len(geom)), (cy / len(geom))))
weights.append(weight)
sumWeight = sum(weights)
cx = 0.00
cy = 0.00
item = 0
for item, i in enumerate(points):
cx += i.x() * weights[item]
cy += i.y() * weights[item]
cx = cx / sumWeight
cy = cy / sumWeight
meanPoint = QgsPoint(cx, cy)
outFeat.setGeometry(QgsGeometry.fromPoint(meanPoint))
outFeat.setAttributes([QVariant(cx), QVariant(cy), QVariant(j)])
writer.addFeature(outFeat)
if single:
break
del writer示例3: processAlgorithm
# 需要导入模块: from sextante.algs.ftools import FToolsUtils [as 别名]
# 或者: from sextante.algs.ftools.FToolsUtils import extractPoints [as 别名]
def processAlgorithm(self, progress):
useField = (self.getParameterValue(ConvexHull.METHOD) == 1)
fieldName = self.getParameterValue(ConvexHull.FIELD)
layer = QGisLayers.getObjectFromUri(self.getParameterValue(ConvexHull.INPUT))
f = QgsField("value")
f.setType(QVariant.String)
f.setLength(255)
if useField:
index = layer.fieldNameIndex(fieldName)
fType = layer.pendingFields()[index].type()
if fType == QVariant.Int:
f.setType(QVariant.Int)
f.setLength(20)
elif fType == QVariant.Double:
f.setType(QVariant.Double)
f.setLength(20)
f.setPrecision(6)
else:
f.setType(QVariant.String)
f.setLength(255)
fields = [QgsField("id", QVariant.Int, "", 20),
f,
QgsField("area", QVariant.Double, "", 20, 6),
QgsField("perim", QVariant.Double, "", 20, 6)
]
writer = self.getOutputFromName(ConvexHull.OUTPUT).getVectorWriter(fields, QGis.WKBPolygon, layer.dataProvider().crs())
outFeat = QgsFeature()
inGeom = QgsGeometry()
outGeom = QgsGeometry()
current = 0
fid = 0
val = ""
if useField:
unique = layer.uniqueValues(index)
total = 100.0 / float(layer.featureCount() * len (unique))
for i in unique:
hull = []
first = True
features = QGisLayers.features(layer)
for f in features:
idVar = f[fieldName]
if unicode(idVar).strip() == unicode(i).strip:
if first:
val = idVar
first = False
inGeom = QgsGeometry(f.geometry())
points = utils.extractPoints(inGeom)
hull.extend(points)
current += 1
progress.setPercentage(int(current * total))
if len(hull) >= 3:
tmpGeom = QgsGeometry(outGeom.fromMultiPoint(hull))
try:
outGeom = tmpGeom.convexHull()
(area, perim) = utils.simpleMeasure(outGeom)
outFeat.setGeometry(outGeom)
outFeat.setAttributes([fid,val,area,perim])
writer.addFeature(outFeat)
except:
raise GeoAlgorithmExecutionException("Exception while computing convex hull")
fid += 1
else:
hull = []
total = 100.0 / float(layer.featureCount())
features = QGisLayers.features(layer)
for f in features:
inGeom = QgsGeometry(f.geometry())
points = utils.extractPoints(inGeom)
hull.extend(points)
current += 1
progress.setPercentage(int(current * total))
tmpGeom = QgsGeometry(outGeom.fromMultiPoint(hull))
try:
outGeom = tmpGeom.convexHull()
(area, perim) = utils.simpleMeasure(outGeom)
outFeat.setGeometry(outGeom)
outFeat.setAttributes([0, "all", area, perim])
writer.addFeature(outFeat)
except:
raise GeoAlgorithmExecutionException("Exception while computing convex hull")
del writer示例4: processAlgorithm
# 需要导入模块: from sextante.algs.ftools import FToolsUtils [as 别名]
# 或者: from sextante.algs.ftools.FToolsUtils import extractPoints [as 别名]
def processAlgorithm(self, progress):
useField = (self.getParameterValue(ConvexHull.METHOD) == 1)
field = self.getParameterValue(ConvexHull.FIELD)
vlayerA = QGisLayers.getObjectFromUri(self.getParameterValue(ConvexHull.INPUT))
GEOS_EXCEPT = True
FEATURE_EXCEPT = True
vproviderA = vlayerA.dataProvider()
#allAttrsA = vproviderA.attributeIndexes()
#vproviderA.select(allAttrsA)
fields = [QgsField("ID", QVariant.Int),
QgsField("Area", QVariant.Double),
QgsField("Perim", QVariant.Double)]
writer = self.getOutputFromName(ConvexHull.OUTPUT).getVectorWriter(fields, QGis.WKBPolygon, vproviderA.crs())
inFeat = QgsFeature()
outFeat = QgsFeature()
inGeom = QgsGeometry()
outGeom = QgsGeometry()
nElement = 0
index = vproviderA.fieldNameIndex(field)
features = QGisLayers.features(vlayerA)
nFeat = len(features)
if useField:
unique = utils.getUniqueValues(vproviderA, index)
nFeat = nFeat * len(unique)
for i in unique:
hull = []
first = True
outID = 0
#vproviderA.select(allAttrsA)
features = QGisLayers.features(vlayerA)
for inFeat in features:
atMap = inFeat.attributes()
idVar = atMap[ index ]
if idVar.toString().trimmed() == i.toString().trimmed():
if first:
outID = idVar
first = False
inGeom = QgsGeometry(inFeat.geometry())
points = utils.extractPoints(inGeom)
hull.extend(points)
nElement += 1
progress.setPercentage(int(nElement / nFeat * 100))
if len(hull) >= 3:
tmpGeom = QgsGeometry(outGeom.fromMultiPoint(hull))
try:
outGeom = tmpGeom.convexHull()
outFeat.setGeometry(outGeom)
(area, perim) = self.simpleMeasure(outGeom)
outFeat.addAttribute(0, QVariant(outID))
outFeat.addAttribute(1, QVariant(area))
outFeat.addAttribute(2, QVariant(perim))
writer.addFeature(outFeat)
except:
GEOS_EXCEPT = False
continue
else:
hull = []
#vproviderA.select(allAttrsA)
features = QGisLayers.features(vlayerA)
for inFeat in features:
inGeom = QgsGeometry(inFeat.geometry())
points = utils.extractPoints(inGeom)
hull.extend(points)
nElement += 1
progress.setPercentage(int(nElement / nFeat * 100))
tmpGeom = QgsGeometry(outGeom.fromMultiPoint(hull))
try:
outGeom = tmpGeom.convexHull()
outFeat.setGeometry(outGeom)
(area, perim) = self.simpleMeasure(outGeom)
#outFeat.addAttribute(0, QVariant("1"))
#outFeat.addAttribute(1, QVariant(area))
#outFeat.addAttribute(2, QVariant(perim))
writer.addFeature(outFeat)
except:
GEOS_EXCEPT = False
del writer
if not GEOS_EXCEPT:
SextanteLog.addToLog(SextanteLog.LOG_WARNING, "Geometry exception while computing convex hull")
if not FEATURE_EXCEPT:
SextanteLog.addToLog(SextanteLog.LOG_WARNING, "Feature exception while computing convex hull")