ArcGIS二次开发——面要素等面积分割
ArcGIS二次开发——面要素等面积分割
本文使用的ArcGIS版本为10.5，python为ArcGIS10.5自带的python（32位2.7.12）。读者如果不想自己写代码，可以修改代码中的polygon、spiltNum和step三个参数，运行结果将保存在当前脚本所在目录下，文件名为result.shp。本教程示例代码运行的结果有一定误差，但可以将误差减小最小，详见输入参数介绍。
本教程所使用的示例代码可能不是很专业，因在实际工作中需要这样的功能，想到的办法。如果你有更好的面要素等面积分割方法欢迎在下方留言。
polygon表示需要拆分的要素，可以是一个shp文件中包含多个polygon。
spiltNum表示将每个多边形分成多少份。
step的含义是：示例代码主要原理是对多边形从左向右扫描的过程，指针不是匀速向右进行，step代表了每次向右的距离，step值越小等面积分割的误差越小，程序运行时间越长。具体step的取值还要参考输入要素的坐标系统，不同坐标系统及地理坐标和投影的情况下差异较大，当然step粗略值的获取对于我们学地理信息专业的人来说几乎没有难度。
# -*- coding: utf-8 -*-
import os
import shapefile
def polygonsplit(polygon, spiltNum, step, outputFile, path_now):
try:
arcpy.AddField_management(polygon, "area", "DOUBLE", 18)
except:
print(u"面积字段已经存在")
arcpy.CalculateField_management(polygon, "area", "!shape.geodesicArea@SQUAREKILOMETERS!", "PYTHON_9.3")
area = 0
with arcpy.da.SearchCursor(polygon, "area") as cursor:
for row in cursor:
area = row[0]
print(u"总面积：" + str(area))
print(u"每块面积：" + str(area / spiltNum))
file = shapefile.Reader(polygon)
shapes = file.shapes()
print(file.bbox)
topx = file.bbox[0]
topy = file.bbox[3]
buttonx = file.bbox[0]
buttony = file.bbox[1]
ltopx = file.bbox[0]
ltopy = file.bbox[3]
lbuttonx = file.bbox[0]
lbuttony = file.bbox[1]
tmparea = 0
topx = file.bbox[0]
topy = file.bbox[3]
buttonx = file.bbox[0]
buttony = file.bbox[1]
for i in xrange(spiltNum):
tmponesplitarea = 0
print(tmponesplitarea)
print(tmparea)
if i < spiltNum - 1:
while tmponesplitarea < (area / spiltNum):
topx = topx + step
topy = topy
buttonx = buttonx + step
buttony = buttony
print(ltopx, ltopy)
print(lbuttonx, lbuttony)
print(topx, topy)
print(buttonx, buttony)
in_table = open("in_table.csv", "w")
in_table.write("x_coords, y_coords\n")
in_table.write("%s,%s\n" % (lbuttonx, lbuttony))
in_table.write("%s,%s\n" % (buttonx, buttony))
in_table.write("%s,%s\n" % (topx, topy))
in_table.write("%s,%s\n" % (ltopx, ltopy))
in_table.close()
spRef = polygon[:-3] + "prj"
out_Layer = "in_memory\\firestations_layer"
arcpy.MakeXYEventLayer_management("in_table.csv", "x_coords", "y_coords", out_Layer, spRef)
arcpy.PointsToLine_management(out_Layer, "in_memory\\PointsToLine_management", "", "", "CLOSE")
arcpy.FeatureToPolygon_management("in_memory\\PointsToLine_management", "in_memory\\FeatureToPolygon_management", "", "ATTRIBUTES", "")
arcpy.Clip_analysis(polygon, "in_memory\\FeatureToPolygon_management", r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "")
arcpy.Delete_management("in_memory\\PointsToLine_management")
try:
arcpy.AddField_management(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area", "DOUBLE", 18)
except:
print(u"面积字段已经存在")
arcpy.CalculateField_management(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area", "!shape.geodesicArea@SQUAREKILOMETERS!", "PYTHON_9.3")
with arcpy.da.SearchCursor(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area") as cursor:
for row in cursor:
tmponesplitarea = row[0]
print(u"临时面积：" + str(tmponesplitarea))
ltopx = topx
ltopy = topy
lbuttonx = buttonx
lbuttony = buttony
else:
print(ltopx, ltopy)
print(lbuttonx, lbuttony)
print(topx, topy)
print(buttonx, buttony)
in_table = open("in_table.csv", "w")
in_table.write("x_coords, y_coords\n")
in_table.write("%s,%s\n" % (buttonx, buttony))
in_table.write("%s,%s\n" % (file.bbox[2], file.bbox[1]))
in_table.write("%s,%s\n" % (file.bbox[2], file.bbox[3]))
in_table.write("%s,%s\n" % (topx, topy))
in_table.close()
spRef = polygon[:-3] + "prj"
out_Layer = "in_memory\\firestations_layer"
arcpy.MakeXYEventLayer_management("in_table.csv", "x_coords", "y_coords", out_Layer, spRef)
arcpy.PointsToLine_management(out_Layer, "in_memory\\PointsToLine_management", "", "", "CLOSE")
arcpy.FeatureToPolygon_management("in_memory\\PointsToLine_management", "in_memory\\FeatureToPolygon_management", "", "ATTRIBUTES", "")
arcpy.Clip_analysis(polygon, "in_memory\\FeatureToPolygon_management", r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "")
arcpy.Delete_management("in_memory\\PointsToLine_management")
arcpy.Delete_management("in_memory\\FeatureToPolygon_management")
try:
arcpy.AddField_management(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area", "DOUBLE", 18)
except:
print(u"面积字段已经存在")
arcpy.CalculateField_management(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area", "!shape.geodesicArea@SQUAREKILOMETERS!", "PYTHON_9.3")
with arcpy.da.SearchCursor(r"data\\tmpresult.gdb\\Clip_analysis" + str(i), "area") as cursor:
for row in cursor:
tmponesplitarea = row[0]
print(u"临时面积：" + str(tmponesplitarea))
#arcpy.Copy_management(r"data\\tmpresult.gdb\\Clip_analysis", "in_memory\\Clip_analysis" + str(i), "ShapeFile")
inputFile = []
for i in xrange(spiltNum):
inputFile.append("data\\tmpresult.gdb\\Clip_analysis" + str(i))
print(inputFile)
arcpy.Merge_management(inputFile, outputFile)
#arcpy.Delete_management("data\\tmpresult.gdb\\Clip_analysis")
try:
arcpy.Delete_management("data\\tmpresult.gdb")
except:
print(u"tmpresult.gdb文件删除失败，但不影响结果")
def fucinit(path_now):
print(u"文件清理")
gdbFile = path_now + "\\data\\tmpresult.gdb"
print(gdbFile)
try:
arcpy.Delete_management(gdbFile)
print(u"删除了缓存文件%s" % gdbFile)
arcpy.CreateFileGDB_management(path_now + "\\data", "tmpresult.gdb")
print(u"创建了缓存文件%s" % gdbFile)
except:
try:
arcpy.CreateFileGDB_management(path_now + "\\data", "tmpresult.gdb")
print(u"创建了缓存文件data\\tmpresult.gdb")
except:
print(u"缓存文件操作失败，可能导致后面处理的结果不正确")
def splitPolygon(polygon):
print(u"文件打散")
shpfilelist = []
tmpfolder = path_now + "\\data\\tmp"
if os.path.exists(tmpfolder) == True:
shutil.rmtree(tmpfolder)
os.mkdir(tmpfolder)
arcpy.Split_analysis(polygon, polygon, "name", tmpfolder, "")
for files in os.walk(tmpfolder):
for onefile in files[2]:
if onefile.endswith(".shp"):
shpfile = files[0] + "\" + onefile
shpfilelist.append(shpfile)
print(shpfile)
return shpfilelist
if __name__ == "__main__":
import arcpy
import os
import shutil
path_now = os.getcwd()
arcpy.gp.overwriteOutput=1
polygon = r"data\Export_Output_2.shp"
spiltNum = 3
step = 300
fucinit(path_now)
splitfilelist = []
for onepolygon in splitPolygon(polygon):
outputFile = polygon[:-3] + "_split.shp"
splitfilelist.append(outputFile)
polygonsplit(onepolygon, spiltNum, step, outputFile, path_now)
arcpy.Merge_management(splitfilelist, path_now + "\\result.shp")
源码下载：https://download.csdn.net/download/bpwangxch/11833434