『基于ArcGIS的Python编程秘籍（第2版）』书本源码

主要摘录一些在学书籍上的源码，方便学习查阅~~~

ArcPy学习

第1章 面向ArcGIS的Python编程语言的基础

• 略

第2章 管理地图文档和图层

• 引用当前的地图文档
• 引用磁盘上的地图文档
• 获取地图文档的图层列表
• 限制图层列表
• 缩放至所选要素
• 改变地图范围
• 添加图层到地图文档
• 插入图层到地图文档
• 更新图层的符号系统
• 更新图层属性
• 操作数据框中的启用时间的图层

1. 引用当前的地图文档2.2-28

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT") # 引用当前活动的地图文档
print(mxd.title)
mxd.title = "Copy of Crime Project"
mxd.saveACopy("c:/ArcpyBook/Ch2/crime_copy.mxd")

1. 引用磁盘上的地图文档2.3-30

import arcpy.mapping as mapping
mxd = mapping.MapDocument("c:/ArcpyBook/Ch2/crime_copy.mxd")
print(mxd.title)

1. 获取地图文档的图层列表2.4-31

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
layers = mapping.ListLayers(mxd)
for lyr in layers:
    print(lyr.name)

1. 限制图层列表2.5-33

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for df in mapping.ListDataFrames(mxd):
    if (df.name == 'Crime'):
        layers = mapping.ListLayers(mxd,"Burg*",df)
        for layer in layers:
            print(layer.name)

1. 缩放至所选要素2.6-35

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd,"Crime")[0]
layer = mapping.ListLayers(mxd,"Burglaries*",df)[0]
df.extent = layer.getSelectedExtent()

1. 改变地图范围2.7-37

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for df in mapping.ListDataFrames(mxd):
    if (df.name == 'Crime'):
        layers = mapping.ListLayers(mxd,'Crime Density by School District',df)
        for layer in layers:
            query = '"NAME" = \'Lackland ISD\''
            layer.definitionQuery = query
            df.extent = layer.getExtent()

1. 添加图层到地图文档2.8-39

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd)[0]
layer = mapping.Layer(r"C:\ArcpyBook\data\School_Districts.lyr")
mapping.AddLayer(df,layer,"AUTO_ARRANGE")

1. 插入图层到地图文档2.9-42

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd, "Crime")[0]
refLayer = mapping.ListLayers(mxd, "Burglaries*", df)[0]
insertLayer = mapping.Layer(r"C:\ArcpyBook\data\CityOfSanAntonio.gdb\Crimes2009")
mapping.InsertLayer(df,refLayer,insertLayer,"BEFORE")

1. 更新图层的符号系统2.10-45

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd, "Crime")[0]
updateLayer = mapping.ListLayers(mxd,"Crime Density by School District",df)[0]
sourceLayer = mapping.Layer(r"C:\ArcpyBook\data\CrimeDensityGradSym.lyr")
mapping.UpdateLayer(df,updateLayer,sourceLayer,True)

1. 更新图层属性2.11-48

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd, "Crime")[0]
updateLayer = mapping.ListLayers(mxd,"Crimes2009",df)[0]
sourceLayer = mapping.Layer(r"C:\ArcpyBook\data\BurglariesNoForcedEntry.lyr")
mapping.UpdateLayer(df,updateLayer,sourceLayer,False)

1. 操作数据框中的启用时间的图层2.12-53

import arcpy.mapping as mapping, os
mxd = mapping.MapDocument("CURRENT")
df = mapping.ListDataFrames(mxd, "Crime")[0]
dft = df.time
dft.currentTime = dft.startTime

while dft.currentTime <= dft.endTime:
    fileName = str(dft.currentTime).split(" ")[0] + ".pdf"
    mapping.ExportToPDF(mxd,os.path.join(r"C:\ArcpyBook\Ch2", fileName))
    print("Exported " + fileName)
    dft.currentTime = dft.currentTime + dft.timeStepInterval

第3章 查找和修复丢失的数据链接

• 查找地图文档和图层文件中丢失的数据源
• 使用MapDocument.findAndReplaceWorkspacePaths()方法修复丢失的数据源
• 使用MapDocument.replaceWorkspaces()方法修复对视的数据源
• 使用replaceDataSource()方法修复单个图层和表对象
• 查找文件夹中所有地图文档内丢失的数据源

1. 查找地图文档和图层文件中丢失的数据源3.2-60

import arcpy.mapping as mapping
mxd = mapping.MapDocument(r"c:\ArcpyBook\Ch3\Crime_BrokenDataLinks.mxd")
listBrokenDS = mapping.ListBrokenDataSources(mxd)
for layer in listBrokenDS:
    print(layer.name)

1. 使用MapDocument.findAndReplaceWorkspacePaths()方法修复丢失的数据源3.3-62

import arcpy.mapping as mapping
mxd = mapping.MapDocument(r"c:\ArcpyBook\Ch3\Crime_BrokenDataLinks.mxd")
mxd.findAndReplaceWorkspacePaths(r"C:\ArcpyBook\Ch3\Data\OldData\CityOfSanAntonio.gdb", r"C:\ArcpyBook\Data\CityOfSanAntonio.gdb")
mxd.saveACopy(r"C:\ArcpyBook\Ch3\Crime_DataLinksFixed.mxd")

1. 使用MapDocument.replaceWorkspaces()方法修复对视的数据源3.4-65

import arcpy.mapping as mapping
mxd = mapping.MapDocument(r"c:\ArcpyBook\Ch3\Crime_DataLinksFixed.mxd")
mxd.replaceWorkspaces(r"c:\ArcpyBook\data\CityOfSanAntonio.gdb", "FILEGDB_WORKSPACE",r"c:\ArcpyBook\new_data\CityOfSanAntonio_Personal.mdb","ACCESS_WORKSPACE")
mxd.saveACopy(r"c:\ArcpyBook\Ch3\Crime_DataLinksUpdated.mxd")

1. 使用replaceDataSource()方法修复单个图层和表对象3.5-68

import arcpy.mapping as mapping
mxd = mapping.MapDocument(r"c:\ArcpyBook\Ch3\Crime_DataLinksLayer.mxd")
df = mapping.ListDataFrames(mxd,"Crime")[0]
lyr = mapping.ListLayers(mxd,"Burglary",df)[0]
lyr.replaceDataSource(r"c:\ArcpyBook\data","SHAPEFILE_WORKSPACE","Burglaries_2009")
mxd.saveACopy(r"c:\ArcpyBook\Ch3\Crime_DataLinksNewLayer.mxd")

1. 查找文件夹中所有地图文档内丢失的数据源3.6-72

import arcpy.mapping as mapping, os
f = open('BrokenDataList.txt', 'w')
for root, dirs, files in os.walk("c:\ArcpyBook"):
    for name in files:
        filename = os.path.join(root, name)
        if ".mxd" in filename:
            mxd = mapping.MapDocument(filename)
            f.write("MXD: " + filename + "\n")
            brknList = mapping.ListBrokenDataSources(mxd)
            for brknItem in brknList:
                print("Broken data item: " +  brknItem.name + " in " + filename)
                f.write("\t" + brknItem.name + "\n")
print("All done")
f.close()

第4章 自动化地图制图和打印

• 创建布局元素的python列表
• 为布局元素指定唯一的名称
• 使用ListLayoutElements()函数限制返回的布局元素
• 更新布局元素的属性
• 获取可用打印机的列表
• 使用PrintMap()函数打印地图
• 导出地图为PDF文件
• 导出地图为图像文件
• 导出报表
• 使用数据驱动页面和ArcPy制图模块构建地图册
• 将地图文档发布为ArcGIS Server服务

1. 创建布局元素的python列表4.2-77

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for el in mapping.ListLayoutElements(mxd):
    if el.name != "":
        print el.name

1. 为布局元素指定唯一的名称4.3-79

None

1. 使用ListLayoutElements()函数限制返回的布局元素4.4-83

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for el in mapping.ListLayoutElements(mxd,"LEGEND_ELEMENT","*Crime*"):
    print el.name

1. 更新布局元素的属性4.5-84

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
elLeg = mapping.ListLayoutElements(mxd, "LEGEND_ELEMENT","*Crime*")[0]
elLeg.title = "Crimes by School District"
for item in elLeg.listLegendItemLayers():
    print item.name

1. 获取可用打印机的列表4.6-87

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for printerName in mapping.ListPrinterNames():
    print printerName

1. 使用PrintMap()函数打印地图4.7-88

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for df in mapping.ListDataFrames(mxd):
    if df.name == "Test_Performance":
        mapping.PrintMap(mxd,"",df)

1. 导出地图为PDF文件4.8-90

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
mapping.ExportToPDF(mxd,r"c:\ArcpyBook\Ch4\Map_PageLayout.pdf")

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for df in mapping.ListDataFrames(mxd):
    if df.name == "Crime":
        df.referenceScale = df.scale
        mapping.ExportToPDF(mxd,r"c:\ArcpyBook\Ch4\DataFrameCrime.pdf",df)

1. 导出地图为图像文件4.9-92

import arcpy.mapping as mapping
mxd = mapping.MapDocument("CURRENT")
for df in mapping.ListDataFrames(mxd):
    if df.name == "Crime":
        mapping.ExportToJPEG(mxd,r"c:\ArcpyBook\Ch4\DataFrameCrime.jpg",df)

1. 导出报表4.10-93

import arcpy
import os 

path = os.getcwd()
 
#Create PDF and remove if it already exists
pdfPath = path + r"\CrimeReport.pdf"
if os.path.exists(pdfPath):
    os.remove(pdfPath)
pdfDoc = arcpy.mapping.PDFDocumentCreate(pdfPath)

districtList = ["Harlandale", "East Central", "Edgewood", "Alamo Heights", "South San Antonio", "Southside", "Ft Sam Houston","North East", "Northside", "Lackland", "Southwest", "Judson", "San Antonio"]

mxd = arcpy.mapping.MapDocument(path + r"\Crime_Ch4.mxd")
df = arcpy.mapping.ListDataFrames(mxd)[0]
lyr = arcpy.mapping.ListLayers(mxd, "Crime Density by School District")[0]

pageCount = 1
for district in districtList:
    #Generate image for each district
    whereClause = "\"NAME\" = '" + district + " ISD'"
    lyr.definitionQuery = whereClause
    arcpy.SelectLayerByAttribute_management(lyr, "NEW_SELECTION", whereClause)
    df.extent = lyr.getSelectedExtent()
    arcpy.SelectLayerByAttribute_management(lyr, "CLEAR_SELECTION")
    arcpy.mapping.ExportToBMP(mxd, path + "\DistrictPicture.bmp", df) #single file

    #Generate report
    print("Generating report for: " + district + " ISD")
    arcpy.mapping.ExportReport(report_source=lyr,report_layout_file=path + r"\CrimeLayout.rlf",output_file=path + r"\temp" + str(pageCount) + ".pdf", starting_page_number=pageCount)

    #Append pages into final output
    print("Appending page: " + str(pageCount))
    pdfDoc.appendPages(path + r"\temp" + str(pageCount) + ".pdf")
    os.remove(path + r"\temp" + str(pageCount) + ".pdf")
    pageCount = pageCount + 1

pdfDoc.saveAndClose()
del mxd

1. 使用数据驱动页面和ArcPy制图模块构建地图册4.11-98

import arcpy
import os

# Create an output directory variable
outDir = r"C:\ArcpyBook\Ch4"  

# Create a new, empty pdf document in the specified output directory
finalpdf_filename = outDir + r"\MapBook.pdf"
if os.path.exists(finalpdf_filename):
  os.remove(finalpdf_filename)
finalPdf = arcpy.mapping.PDFDocumentCreate(finalpdf_filename)

# Add the title page to the pdf
print("Adding the title page  \n")
finalPdf.appendPages(outDir + r"\TitlePage.pdf")

# Add the index map to the pdf
print "Adding the index page  \n"
finalPdf.appendPages(outDir + r"\MapIndex.pdf")

# Export the Data Driven Pages to a temporary pdf and then add it to the
# final pdf. Alternately, if your Data Driven Pages have already been
# exported, simply append that document to the final pdf.
mxdPath = outDir + r"\Topographic.mxd"
mxd = arcpy.mapping.MapDocument(mxdPath)
print("Creating the data driven pages \n")
ddp = mxd.dataDrivenPages
temp_filename = outDir + r"\tempDDP.pdf"

if os.path.exists(temp_filename):
  os.remove(temp_filename)
ddp.exportToPDF(temp_filename, "ALL")
print("Appending the map series  \n")
finalPdf.appendPages(temp_filename)

# Update the properties of the final pdf
finalPdf.updateDocProperties(pdf_open_view="USE_THUMBS",
                             pdf_layout="SINGLE_PAGE")

# Save your result
finalPdf.saveAndClose()

# remove the temporary data driven pages file
if os.path.exists(temp_filename):
    print("Removing the temporary map series file")
    os.remove(temp_filename)

# Delete variables
#del finalPdf, mxd, ddp

1. 将地图文档发布为ArcGIS Server服务4.12-102

import arcpy.mapping as mapping
wrkspc = r'c:\ArcpyBook\ch4'
mxd = mapping.MapDocument(wrkspc + r"\Crime.mxd")

service = 'Crime'
sddraft = wrkspc + service + '.sddraft'
mapping.CreateMapSDDraft(mxd, sddraft, service)
analysis = mapping.AnalyzeForSD(wrkspc + "Crime.sddraft")

for key in ('messages', 'warnings', 'errors'):
    print("----" + key.upper() + "----")
    vars = analysis[key]
    for ((message, code), layerlist) in vars.iteritems():
        print "    ", message, " (CODE %i)" % code
        print("     applies to:")
        for layer in layerlist:
            print(layer.name)

第5章 使用脚本执行地理处理工具

• 查找地理处理工具
• 查看工具箱别名
• 使用脚本执行地理处理工具
• 讲一个工具的输出作为另一个工具的输入

1. 查找地理处理工具5.2-110

None

1. 查看工具箱别名5.3-114

None

1. 使用脚本执行地理处理工具5.4-116

import arcpy
in_features = "c:/ArcpyBook/data/CityOfSanAntonio.gdb/Burglary"
clip_features = "c:/ArcpyBook/Ch5/EdgewoodSD.shp"
out_feature_class = "c:/ArcpyBook/Ch5/ClpBurglary.shp"
arcpy.Clip_analysis(in_features,clip_features,out_feature_class)

1. 讲一个工具的输出作为另一个工具的输入5.5-119

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/TravisCounty"
try:
    # Buffer areas of impact around major roads
    streams = "Streams.shp"
    streamsBuffer = "StreamsBuffer"
    distance = "2640 Feet"
    schools2mile = "Schools.shp"
    schoolsLyrFile = 'Schools2Mile_lyr'
    
    arcpy.Buffer_analysis(streams, streamsBuffer, distance,'FULL','ROUND','ALL')

    # Make a layer
    arcpy.MakeFeatureLayer_management(schools2mile, schoolsLyrFile) 
    arcpy.SelectLayerByLocation_management(schoolsLyrFile, 'intersect', streamsBuffer)
except Exception as e:
    print e.message

第6章 创建自定义地理处理工具

• 创建自定义地理处理工具
• 创建Python工具箱

1. 创建自定义地理处理工具6.2-123

#Script to Import data to a feature class within a geodatabase
import arcpy, os
try:
    outputFC = arcpy.GetParameterAsText(0)
    fClassTemplate = arcpy.GetParameterAsText(1)
    f = open(arcpy.GetParameterAsText(2),'r')
    arcpy.CreateFeatureclass_management(os.path.split(outputFC)[0], os.path.split(outputFC)[1],"point",fClassTemplate)   
    lstFires = f.readlines()
    with arcpy.da.InsertCursor(outputFC) as cur:
        cntr = 1
        for fire in lstFires:
            if 'Latitude' in fire:
                continue
            vals = fire.split(",")
            latitude = float(vals[0])
            longitude = float(vals[1])
            confid = int(vals[2])
            pnt = arcpy.Point(longitude, latitude)
            feat = cur.newRow()
            feat.shape = pnt
            feat.setValue("CONFIDENCEVALUE", confid)
            cur.insertRow(feat)
            arcpy.AddMessage("Record number" + str(cntr) + "written to feature class")
            cntr = cntr + 1
except:
    print arcpy.GetMessages()
finally:
    f.close()

1. 创建Python工具箱6.3-139

import arcpy
import requests
import json

class Toolbox(object):
    def __init__(self):
        """Define the toolbox (the name of the toolbox is the name of the
        .pyt file)."""
        self.label = "Toolbox"
        self.alias = ""

        # List of tool classes associated with this toolbox
        self.tools = [USGSDownload]


class USGSDownload(object):
    def __init__(self):
        """Define the tool (tool name is the name of the class)."""
        self.label = "USGS Download"
        self.description = "Download from USGS ArcGIS Server instance"
        self.canRunInBackground = False

    def getParameterInfo(self):

        """Define parameter definitions"""
        # First parameter
        param0 = arcpy.Parameter(
            displayName="ArcGIS Server Wildfire URL",
            name="url",
            datatype="GPString",
            parameterType="Required",
            direction="Input")
        param0.value = "http://wildfire.cr.usgs.gov/arcgis/rest/services/geomac_dyn/MapServer/0/query"

        # Second parameter
        param1 = arcpy.Parameter(
            displayName="Output Feature Class",
            name="out_fc",
            datatype="DEFeatureClass",
            parameterType="Required",
            direction="Input")

        params = [param0, param1]
        return params

    def isLicensed(self):
        """Set whether tool is licensed to execute."""
        return True

    def updateParameters(self, parameters):
        """Modify the values and properties of parameters before internal
        validation is performed.  This method is called whenever a parameter
        has been changed."""
        return

    def updateMessages(self, parameters):
        """Modify the messages created by internal validation for each tool
        parameter.  This method is called after internal validation."""
        return

    def execute(self, parameters, messages):
        inFeatures = parameters[0].valueAsText
        outFeatureClass = parameters[1].valueAsText

        agisurl = inFeatures

        payload = { 'where': 'acres > 5','f': 'pjson', 'outFields': 'latitude,longitude,fire_name,acres'}

        r = requests.get(inFeatures, params=payload)
        decoded = json.loads(r.text)

        with arcpy.da.InsertCursor(outFeatureClass, ("SHAPE@XY", "NAME", "ACRES")) as cur:
            cntr = 1
            for rslt in decoded['features']:
                fireName = rslt['attributes']['fire_name']
                latitude = rslt['attributes']['latitude']
                longitude = rslt['attributes']['longitude']
                acres = rslt['attributes']['acres']
                cur.insertRow([(longitude,latitude),fireName, acres])
                arcpy.AddMessage("Record number: " + str(cntr) + " written to feature class")
                cntr = cntr + 1

第7章 查询和选择数据

• 构造正确的属性查询语句
• 创建要素图层和表现层
• 使用Select Layer by Attribute 工具选择要素和行
• 使用Select Layer by Location 工具选择要素
• 结合空间查询和属性选择要素

1. 构造正确的属性查询语句7.2-149

None

1. 创建要素图层和表现层7.3-154

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    tView = arcpy.MakeTableView_management("Crime2009Table","Crime2009TView")
except Exception as e:
    print e.message

1. 使用Select Layer by Attribute 工具选择要素和行7.4-158

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    qry = '"SVCAREA" = \'North\''
    flayer = arcpy.MakeFeatureLayer_management("Burglary","Burglary_Layer")
    arcpy.SelectLayerByAttribute_management(flayer, "NEW_SELECTION", qry)
    cnt = arcpy.GetCount_management(flayer)
    print "The number of selected records is: " + str(cnt)
except Exception as e:
    print e.message

1. 使用Select Layer by Location 工具选择要素7.5-161

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    flayer = arcpy.MakeFeatureLayer_management("Burglary","Burglary_Layer")
    arcpy.SelectLayerByLocation_management(flayer, "COMPLETELY_WITHIN", "c:/ArcpyBook/Ch7/EdgewoodSD.shp")
    cnt = arcpy.GetCount_management(flayer)
    print("The number of selected records is: " + str(cnt))
except Exception as e:
    print(e.message)

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    flayer = arcpy.MakeFeatureLayer_management("Burglary","Burglary_Layer")
    arcpy.SelectLayerByLocation_management (flayer, "WITHIN_A_DISTANCE", "c:/ArcpyBook/Ch7/EdgewoodSD.shp","1 MILES")
    cnt = arcpy.GetCount_management(flayer)
    print("The number of selected records is: " + str(cnt))
except Exception as e:
    print(e.message)

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    flayer = arcpy.MakeFeatureLayer_management("Burglary","Burglary_Layer")
    arcpy.SelectLayerByLocation_management (flayer, "WITHIN_A_DISTANCE", "c:/ArcpyBook/Ch7/EdgewoodSD.shp","1 MILES")
    arcpy.CopyFeatures_management(flayer, "c:/ArcpyBook/Ch7/EdgewoodBurglaries.shp") 
    ##cnt = arcpy.GetCount_management(flayer)
    ##print "The number of selected records is: " + str(cnt)
except Exception as e:
    print(e.message)

1. 结合空间查询和属性选择要素7.6-165

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    qry = '"DOW" = \'Mon\''
    flayer = arcpy.MakeFeatureLayer_management("Burglary","Burglary_Layer")
    arcpy.SelectLayerByLocation_management (flayer, "COMPLETELY_WITHIN", "c:/ArcpyBook/Ch7/EdgewoodSD.shp")
    arcpy.SelectLayerByAttribute_management(flayer, "SUBSET_SELECTION", qry)
    cnt = arcpy.GetCount_management(flayer)
    print("The total number of selected records is: " + str(cnt))
except Exception as e:
    print(e.message)

第8章 在要素类和表中使用ArcPy数据访问模块

• 使用SearchCursor检索要素类中的要素
• 使用where字句筛选记录
• 使用几何令爱改进游标性能
• 使用InsertCursor插入行
• 使用UpdateCursor更新行
• 使用UpdateCursor删除行
• 在编辑会话中插入和更新行
• 读取要素类中的几何信息
• 使用Walk()遍历目录

1. 使用SearchCursor检索要素类中的要素8.2-171

import arcpy.da
arcpy.env.workspace = "c:/ArcpyBook/Ch8"
with arcpy.da.SearchCursor("Schools.shp",("Facility","Name")) as cursor:
    for row in sorted(cursor):
        print("High school name: " + row[1])

1. 使用where字句筛选记录8.3-173

import arcpy.da
arcpy.env.workspace = "c:/ArcpyBook/Ch8"
with arcpy.da.SearchCursor("Schools.shp",("Facility","Name"), '"FACILITY" = \'HIGH SCHOOL\'') as cursor:
        for row in sorted(cursor):
                print("School name: " + row[1])

1. 使用几何令爱改进游标性能8.4-174

import arcpy.da
import time
arcpy.env.workspace = "c:/ArcpyBook/Ch8"
start = time.clock()
with arcpy.da.SearchCursor("coa_parcels.shp",("PY_FULL_OW","SHAPE@XY")) as cursor:
    for row in cursor:
        print("Parcel owner: {0} has a location of: {1}".format(row[0], row[1]))
elapsed = (time.clock() - start)
print("Execution time: " + str(elapsed))

1. 使用InsertCursor插入行8.5-178

import arcpy
import os

arcpy.env.workspace = "C:/ArcpyBook/Ch8/WildfireData/WildlandFires.mdb"
f = open("C:/ArcpyBook/Ch8/WildfireData/NorthAmericaWildfires_2007275.txt","r")
lstFires = f.readlines()
try:
        with arcpy.da.InsertCursor("FireIncidents",("SHAPE@XY","CONFIDENCEVALUE")) as cur:
                cntr = 1
                for fire in lstFires:
                        if 'Latitude' in fire:
                                continue
                        vals = fire.split(",")
                        latitude = float(vals[0])
                        longitude = float(vals[1])
                        confid = int(vals[2])
                        rowValue = [(latitude,longitude),confid]
                        cur.insertRow(rowValue)
                        print("Record number " + str(cntr) + " written to feature class")
                        cntr = cntr + 1
except Exception as e:
        print(e.message)
finally:
    f.close()

1. 使用UpdateCursor更新行8.6-183

import arcpy

arcpy.env.workspace = "C:/ArcpyBook/Ch8/WildfireData/WildlandFires.mdb"
try:
    #create a new field to hold the values
    arcpy.AddField_management("FireIncidents","CONFID_RATING","TEXT","10")
    print("CONFID_RATING field added to FireIncidents")
    with arcpy.da.UpdateCursor("FireIncidents",("CONFIDENCEVALUE","CONFID_RATING")) as cursor:
        cntr = 1
        for row in cursor:
            # update the confid_rating field
            if row[0] <= 40:
                row[1] = 'POOR'
            elif row[0] > 40 and row[0] <= 60:
                row[1] = 'FAIR'
            elif row[0] > 60 and row[0] <= 85:
                row[1] = 'GOOD'
            else:
                row[1] = 'EXCELLENT'
            cursor.updateRow(row)
            print("Record number " + str(cntr) + " updated")
            cntr = cntr + 1
except Exception as e:
    print(e.message)

1. 使用UpdateCursor删除行8.7-187

import arcpy
import os

arcpy.env.workspace = "C:/ArcpyBook/Ch8/WildfireData/WildlandFires.mdb"
try:
    with arcpy.da.UpdateCursor("FireIncidents",("CONFID_RATING"),'[CONFID_RATING] = \'POOR\'') as cursor:
        cntr = 1
        for row in cursor:
            cursor.deleteRow()
            print("Record number " + str(cntr) + " deleted")
            cntr = cntr + 1
except Exception as e:
    print(e.message)

1. 在编辑会话中插入和更新行8.8-189

import arcpy
import os

arcpy.env.workspace = "C:/ArcpyBook/Ch8/WildfireData/WildlandFires.mdb"
try:
    edit = arcpy.da.Editor('C:/ArcpyBook/Ch8/WildfireData/WildlandFires.mdb')
    edit.startEditing(True)
    with arcpy.da.UpdateCursor("FireIncidents",("CONFIDENCEVALUE","CONFID_RATING")) as cursor:
        cntr = 1
        for row in cursor:
            # update the confid_rating field
            if row[0] > 40 and row[0] <= 60:
                row[1] = 'GOOD'
            elif row[0] > 60 and row[0] <= 85:
                row[1] = 'BETTER'
            else:
                row[1] = 'BEST'
            cursor.updateRow(row)
            print("Record number " + str(cntr) + " updated")
            cntr = cntr + 1
    edit.stopEditing(True)
except Exception as e:
    print(e.message)

1. 读取要素类中的几何信息8.9-193

import arcpy
infc = "c:/ArcpyBook/data/CityOfSanAntonio.gdb/SchoolDistricts"
# Enter for loop for each feature
for row in arcpy.da.SearchCursor(infc, ["OID@", "SHAPE@"]):
    # Print the current multipoint's ID
    print("Feature {0}:".format(row[0]))
    partnum = 0

    # Step through each part of the feature
    #
    for part in row[1]:
        # Print the part number
        #
        print("Part {0}:".format(partnum))

        # Step through each vertex in the feature
        #
        for pnt in part:
            if pnt:
                # Print x,y coordinates of current point
                #
                print("{0}, {1}".format(pnt.X, pnt.Y))
            else:
                # If pnt is None, this represents an interior ring
                #
                print("Interior Ring:")
        partnum += 1

1. 使用Walk()遍历目录8.10-195

import arcpy.da as da
import os

print("os walk")

for dirpath, dirnames, filenames in os.walk(os.getcwd()):
    for filename in filenames:
        print(filename)

print("arcpy da walk")

for dirpath, dirnames, filenames in da.Walk(os.getcwd(),datatype="FeatureClass"):
    for filename in filenames:
        print(os.path.join(dirpath, filename))

第9章 获取GIS数据的列表和描述

• 使用ArcPy列表函数
• 获取要素类或表中的字段列表
• 使用Describe()函数返回要素类的描述性信息
• 使用Describe()函数返回栅格图像的描述性信息

1. 使用ArcPy列表函数9.2-199

import arcpy
arcpy.env.workspace = "C:/ArcpyBook/data/CityOfSanAntonio.gdb"
fcList = arcpy.ListFeatureClasses()
for fc in fcList:
    print(fc)

import arcpy
arcpy.env.workspace = "C:/ArcpyBook/data/CityOfSanAntonio.gdb"
fcList = arcpy.ListFeatureClasses("C*")
for fc in fcList:
    print(fc)

import arcpy
arcpy.env.workspace = "C:/ArcpyBook/data/CityOfSanAntonio.gdb"
fcList = arcpy.ListFeatureClasses("C*","polygon")
for fc in fcList:
    print(fc)

1. 获取要素类或表中的字段列表9.3-202

import arcpy

arcpy.env.workspace = "C:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    fieldList = arcpy.ListFields("Burglary")
    for fld in fieldList:
        print("%s is a type of %s with a length of %i" % (fld.name, fld.type, fld.length))
except Exception as e:
    print(e.message)

1. 使用Describe()函数返回要素类的描述性信息9.4-204

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    descFC = arcpy.Describe("Burglary")
    print("The shape type is: " + descFC.ShapeType)
    flds = descFC.fields
    for fld in flds:
        print("Field: " + fld.name)
        print("Type: " + fld.type)
        print("Length: " + str(fld.length))
    ext = descFC.extent
    print("XMin: %f" % (ext.XMin))
    print("YMin: %f" % (ext.YMin))
    print("XMax: %f" % (ext.XMax))
    print("YMax: %f" % (ext.YMax))
except:
    print(arcpy.GetMessages())

1. 使用Describe()函数返回栅格图像的描述性信息9.5-208

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data"
try:
    descRaster = arcpy.Describe("AUSTIN_EAST_NW.sid")
    ext = descRaster.extent
    print("XMin: %f" % (ext.XMin))
    print("YMin: %f" % (ext.YMin))
    print("XMax: %f" % (ext.XMax))
    print("YMax: %f" % (ext.YMax))
    
    sr = descRaster.SpatialReference
    print(sr.name)
    print(sr.type)
except Exception as e:
    print e.message

第10章 使用Add-in定制ArcGIS界面

• 下载并安装Python Add-in Wizard
• 创建按钮加载项和使用Python加载项模块
• 安装和测试加载项
• 创建工具加载项

1. 下载并安装Python Add-in Wizard10.2-212

None

1. 创建按钮加载项和使用Python加载项模块10.3-214

import arcpy
import pythonaddins

class ButtonClassImportWildfires(object):
    """Implementation for Wildfire_addin.button (Button)"""
    def __init__(self):
        self.enabled = True
        self.checked = False

    def onClick(self):
        layer_files = pythonaddins.OpenDialog('Select Layers to Add', True, r'C:\ArcpyBook\data\Wildfires', 'Add')
        mxd = arcpy.mapping.MapDocument('current')
        df = pythonaddins.GetSelectedTOCLayerOrDataFrame()
        if not isinstance(df, arcpy.mapping.Layer):
            for layer_file in layer_files:
                layer = arcpy.mapping.Layer(layer_file)
                arcpy.mapping.AddLayer(df, layer)
        else:
            pythonaddins.MessageBox('Select a data frame', 'INFO', 0)

1. 安装和测试加载项10.4-223

None

1. 创建工具加载项10.5-228

import arcpy
import pythonaddins

def __init__(self):
  self.enabled = True
  self.cursor = 3
  self.shape = 'Rectangle'

def onRectangle(self, rectangle_geometry):
    extent = rectangle_geometry
    arcpy.env.workspace = r'c:\ArcpyBook\Ch10'
    if arcpy.Exists('randompts.shp'):
        arcpy.Delete_management('randompts.shp')
        randompts = arcpy.CreateRandomPoints_management(arcpy.env.workspace,'randompts.shp',"",rectangle_geometry)
        arcpy.RefreshActiveView()
    return randompts

第11章 异常识别和错误处理

• 默认的Python错误消息
• 添加Python异常处理结构(try/except/else)
• 使用GetMessages()函数获取工具消息
• 根据严重性级别筛选工具消息
• 测试和响应特定的错误消息

1. 默认的Python错误消息11.2-235

import arcpy
arcpy.env.workspace = "c:/ArcpyBook/data"
arcpy.Buffer_analysis("Streams.shp","Streams_Buff.shp")

1. 添加Python异常处理结构(try/except/else)11.3-236

import arcpy
try:
    arcpy.env.workspace = "c:/ArcpyBook/data"
    arcpy.Buffer_analysis("Streams.shp","Streams_Buff.shp")
except:
    print("Error")

1. 使用GetMessages()函数获取工具消息11.4-238

import arcpy
try:
    arcpy.env.workspace = "c:/ArcpyBook/data"
    arcpy.Buffer_analysis("Streams.shp","Streams_Buff.shp")
except:
    print(arcpy.GetMessages())

1. 根据严重性级别筛选工具消息11.5-240

import arcpy
try:
    arcpy.env.workspace = "c:/ArcpyBook/data"
    arcpy.Buffer_analysis("Streams.shp","Streams_Buff.shp")
except:
    print(arcpy.GetMessages(2))

1. 测试和响应特定的错误消息116-241

import arcpy
try:
    arcpy.env.workspace = "c:/ArcpyBook/data"
    arcpy.Buffer_analysis("Streams.shp", "Streams_Buff.shp")
except:
    print("Error found in Buffer tool \n")
    errCode = arcpy.GetReturnCode(3)
    if str(errCode) == "735":
        print("Distance value not provided \n")
        print("Running the buffer again with a default value \n")
        defaultDistance = "100 Feet"
        arcpy.Buffer_analysis("Streams.shp", "Streams_Buff", defaultDistance)
        print("Buffer complete")

第12章 使用Python实现ArcGIS的高级功能

• ArcGIS REST API入门
• 使用Python构建HTTP请求并解析响应
• 使用ArcGIS REST API和Python获取图层信息
• 使用ArcGIS REST API和Python导出地图
• 使用ArcGIS REST API和Python查询地图服务
• 使用ESRI World Geocoding Service镜像地理编码
• 使用FieldMap和FieldMappings
• 使用ValueTable将多值输入到工具中

1. ArcGIS REST API入门12.2-245

None

1. 使用Python构建HTTP请求并解析响应12.3-250

import requests
import json

agisurl = "http://server.arcgisonline.com/arcgis/rest/services?f=pjson"
r = requests.get(agisurl)
decoded = json.loads(r.text)
print(decoded)
#print(r.text)

1. 使用ArcGIS REST API和Python获取图层信息12.4-254

import requests
import json

agisurl = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer/1"
payload = { 'where': 'STATE_FIPS = \'48\' and CNTY_FIPS = \'021\'','returnCountyOnly': 'false', 
            'returnIdsOnly': 'false', 'returnGeometry': 'false',  
            'f': 'pjson'}

r = requests.get(agisurl, params=payload)
#r = requests.get(agisurl)
#print(r.text)

decoded = json.loads(r.text)
print("The layer name is: " + decoded['name'])
print("The xmin: " + str(decoded['extent']['xmin']))
print("The xmax: " + str(decoded['extent']['xmax']))
print("The ymin: " + str(decoded['extent']['ymin']))
print("The ymax: " + str(decoded['extent']['xmax']))
print("The fields in this layer: ")
for rslt in decoded['fields']:
    print(rslt['name'])

1. 使用ArcGIS REST API和Python导出地图12.5-257

import requests
import json

agisurl = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Specialty/ESRI_StateCityHighway_USA/MapServer/export"


payload = { 'bbox': '-115.8,30.4,-85.5,50.5','size': '800,600', \
            'imageSR': '102004', 'format': 'gif', 'transparent':'false', \
            'f': 'pjson'}

r = requests.get(agisurl, params=payload)
print(r.text)

1. 使用ArcGIS REST API和Python查询地图服务12.6-260

import requests
import json

agisurl = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer/1/query"
payload = { 'where': 'STATE_FIPS = \'48\' and CNTY_FIPS = \'021\'','returnCountyOnly': 'false',
            'returnIdsOnly': 'false', 'returnGeometry': 'false', 'outFields':'POP2000,POP2007,BLKGRP',
            'f': 'pjson'}


r = requests.get(agisurl, params=payload)
#print(r.text)

decoded = json.loads(r.text)
#print(decoded)


for rslt in decoded['features']:
    print("Block Group: " + str(rslt['attributes']['BLKGRP']))
    print("Population 2000: " + str(rslt['attributes']['POP2000']))
    print("Population 2007: " + str(rslt['attributes']['POP2007']))

1. 使用ESRI World Geocoding Service镜像地理编码12.7-264

import requests
import json

agisurl = "http://geocode.arcgis.com/arcgis/rest/services/World/GeocodeServer/find"

payload = { 'text': '1202 Sand Wedge, San Antonio, TX, 78258', 'f': 'pjson'}

r = requests.get(agisurl, params=payload)

decoded = json.loads(r.text)
print("The geocoded address: " + decoded['locations'][0]['name'])
print("The longitude: " + str(decoded['locations'][0]['feature']['geometry']['x']))
print("The latitude: " + str(decoded['locations'][0]['feature']['geometry']['y']))
print("The geocode score: " + str(decoded['locations'][0]['feature']['attributes']['Score']))
print("The address type: " + decoded['locations'][0]['feature']['attributes']['Addr_Type'])

1. 使用FieldMap和FieldMappings12.8-266

import arcpy

try:
    # Local variables

    arcpy.env.workspace = r"c:\ArcpyBook\data"
    outFeatureClass = r"c:\ArcpyBook\data\AllTracts.shp"

    # Create a fieldmappings adding the three new fields
    fieldmappings = arcpy.FieldMappings()
    fldmap_STFIPS = arcpy.FieldMap()
    fldmap_COFIPS = arcpy.FieldMap()
    fldmap_TRACT = arcpy.FieldMap()

    # List all feature classes that start with 'County' and type Polygon
    fclss = arcpy.ListFeatureClasses("County*", "Polygon")

    # Create a value table with the FC to merge
    vTab = arcpy.ValueTable()
    for fc in fclss:
        fieldmappings.addTable(fc)
        fldmap_STFIPS.addInputField(fc, "STFID")
        fldmap_COFIPS.addInputField(fc, "STFID")
        fldmap_TRACT.addInputField(fc, "STFID")
        vTab.addRow(fc)

    # Set Starting and ending point from the input as well as the name of the output fields 

    # STFIPS field
    for x in range(0, fldmap_STFIPS.inputFieldCount):
        fldmap_STFIPS.setStartTextPosition(x, 0)
        fldmap_STFIPS.setEndTextPosition(x, 1)

    fld_STFIPS = fldmap_STFIPS.outputField
    fld_STFIPS.name = "STFIPS"
    fldmap_STFIPS.outputField = fld_STFIPS

    # COFIPS field
    for x in range(0, fldmap_COFIPS.inputFieldCount):
        fldmap_COFIPS.setStartTextPosition(x, 2)
        fldmap_COFIPS.setEndTextPosition(x, 4)

    fld_COFIPS = fldmap_COFIPS.outputField
    fld_COFIPS.name = "COFIPS"
    fldmap_COFIPS.outputField = fld_COFIPS

    # TRACT field
    for x in range(0, fldmap_TRACT.inputFieldCount):
        fldmap_TRACT.setStartTextPosition(x, 5)
        fldmap_TRACT.setEndTextPosition(x, 12)

    fld_TRACT = fldmap_TRACT.outputField
    fld_TRACT.name = "TRACT"
    fldmap_TRACT.outputField = fld_TRACT

    # Add fieldmaps into the fieldmappings object
    fieldmappings.addFieldMap(fldmap_STFIPS)
    fieldmappings.addFieldMap(fldmap_COFIPS)
    fieldmappings.addFieldMap(fldmap_TRACT)

    # Run the merge tool
    arcpy.Merge_management(vTab, outFeatureClass, fieldmappings)

    print("Merge completed")
               
except Exception as e:
    print(e.message)

1. 使用ValueTable将多值输入到工具中12.9-273

import arcpy
try:

    arcpy.env.workspace = r'c:\ArcpyBook\data'

    vTab = arcpy.ValueTable()

    vTab.setRow (0, "5")
    vTab.setRow (1, "10")
    vTab.setRow (2, "20")

    inFeature = 'Hospitals.shp'
    outFeature = 'HospitalMBuff.shp'
    dist = vTab
    bufferUnit = "meters"

    arcpy.MultipleRingBuffer_analysis(inFeature,outFeature,dist,bufferUnit, '', 'ALL')
    print("Multi-Ring Buffer Complete")
except Exception as e:
    print(e.message)

附录A 自动化Python脚本

• 在命令行中运行Python脚本
• 使用sys.argv[]捕获命令行的输入
• 添加Python脚本到批处理文件
• 在规定的时间运行批处理文件

1. 在命令行中运行Python脚本A.2-283

None

1. 使用sys.argv[]捕获命令行的输入A.3-289

import arcpy

arcpy.env.workspace = "C:/ArcpyBook/data/CityOfSanAntonio.gdb"
try:
    fieldList = arcpy.ListFields("Burglary")
    for fld in fieldList:
        print "%s is a type of %s with a length of %i" % (fld.name, fld.type, fld.length)
except Exception as e:
    print(e.message)

import arcpy
import sys

wkspace = sys.argv[1]
fc = sys.argv[2]
try:
  arcpy.env.workspace = wkspace
  fields = arcpy.ListFields(fc)
  for fld in fields:
    print(fld.name)
except Exception as e:
  print(e.message)

1. 添加Python脚本到批处理文件A.4-290

cd c:\ArcpyBook\Appendix1
python ListFields.py c:\ArcpyBook\data Burglaries_2009.shp

1. 在规定的时间运行批处理文件A.5-292

None

附录B GIS程序员不可不知的5个Python功能

• 读取带分隔符的文本文件
• 发送电子邮件
• 检索FTP服务中的文件
• 创建ZIP文件
• 读取XML文件

1. 读取带分隔符的文本文件B.2-298

f = open('c:/ArcpyBook/data/N_America.A2007275.txt','r')
for fire in f:
    lstValues = fire.split(',')
    latitude = float(lstValues[0])
    longitude = float(lstValues[1])
    confid = int(lstValues[8])
    print("The latitude is: " + str(latitude) + " The longitude is: " + str(longitude) + " The confidence value is: " + str(confid))
f.close()

1. 发送电子邮件B.3-301

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email import Encoders
import os

gmail_user = "<username>"
gmail_pwd = "<password>"

def mail(to, subject, text, attach):
   msg = MIMEMultipart()

   msg['From'] = gmail_user
   msg['To'] = to
   msg['Subject'] = subject

   msg.attach(MIMEText(text))

   part = MIMEBase('application', 'octet-stream')
   part.set_payload(open(attach, 'rb').read())
   Encoders.encode_base64(part)
   part.add_header('Content-Disposition',
           'attachment; filename="%s"' % os.path.basename(attach))
   msg.attach(part)

   mailServer = smtplib.SMTP("smtp.gmail.com", 587)
   mailServer.ehlo()
   mailServer.starttls()
   mailServer.ehlo()
   mailServer.login(gmail_user, gmail_pwd)
   mailServer.sendmail(gmail_user, to, msg.as_string())
   mailServer.close()

mail("<email to send to>",
   "Hello from python!",
   "This is an email sent with python",
   "bc_pop1996.csv")

1. 检索FTP服务中的文件B.4-306

import ftplib
import os
import socket

HOST = 'ftp.nifc.gov'
DIRN = '/Incident_Specific_Data/2012 HISTORIC/ROCKY_MTN/Arapaho/GIS/20120629'
FILE = '20120629_0600_Arapaho_PIO_0629_8x11_land.pdf'

try:
    f = ftplib.FTP(HOST)
except (socket.error, socket.gaierror), e:
    print('ERROR: cannot reach "%s"' % HOST)
print('*** Connected to host "%s"' % HOST)

try:
    f.login()
except ftplib.error_perm:
    print('ERROR: cannot login anonymously')
    f.quit()
print('*** Logged in as "anonymous"')

try:
    f.cwd(DIRN)
except ftplib.error_perm:
    print('ERROR: cannot CD to "%s"' % DIRN)
    f.quit()
print('*** Changed to "%s" folder' % DIRN)

try:
    f.retrbinary('RETR %s' % FILE,
          open(FILE, 'wb').write)
except ftplib.error_perm:
    print('ERROR: cannot read file "%s"' % FILE)
    os.unlink(FILE)
else:
    print('*** Downloaded "%s" to CWD' % FILE)
f.quit()

1. 创建ZIP文件B.5-310

import os
import zipfile

#create the zip file
zfile = zipfile.ZipFile("shapefiles2.zip", "w", zipfile.ZIP_STORED)
files = os.listdir("c:/ArcpyBook/data")

for f in files:
    if f.endswith("shp") or f.endswith("dbf") or f.endswith(".shx"):
        zfile.write("C:/ArcpyBook/data/" + f)

#list files in the archive
for f in zfile.namelist():
        print("Added %s" % f)

zfile.close()

import os
import zipfile

#create the zip file
zfile = zipfile.ZipFile("shapefiles2.zip", "w", zipfile.ZIP_DEFLATED)
files = os.listdir("c:/ArcpyBook/data")

for f in files:
    if f.endswith("shp") or f.endswith("dbf") or f.endswith(".shx"):
        zfile.write("C:/ArcpyBook/data/" + f)

#list files in the archive
for f in zfile.namelist():
        print("Added %s" % f)

zfile.close()

1. 读取XML文件B.6-313

from xml.dom import minidom

xmldoc = minidom.parse("WitchFireResidenceDestroyed.xml")

childNodes = xmldoc.childNodes

eList = childNodes[0].getElementsByTagName("fire")
for e in eList:
    if e.hasAttribute("address"):
        print e.getAttribute("address")

箴言：因为这些东西是非常简单的。不要抱怨自己学不会，那是因为你没有足够用心。