python 读取全国城市aqi数据，差值生成png图片

# -*- coding: utf-8 -*-

import arcpy

import sys

import datetime

import cx_Oracle

import json

import os

import time

import uuid

from arcpy import env

from arcpy.sa import *

env.workspace = r"F:\py";

mapPath =  r"F:\py";

imagepath = r'F:\py\images\2016-06-07'

arcpy.AddMessage("1.查询数据库");

cnxn = cx_Oracle.connect('jinan/jinan@127.0.0.1:1521/orcl')

cursor = cnxn.cursor();

sql = "select citycode,aqi from city ";

cursor.execute(sql);

cursorData = cursor ;

arcpy.AddMessage("2.数据保存到fc");

for item in cursorData:

    print item[0]+'-'+item[1];

    fc = "F:\py\jinan.gdb/city";

    where = "CITYCODE=" +item[0];

    rows = arcpy.UpdateCursor(fc,where);

    for row in rows:

        row.setValue('aqi1',item[1]);

        rows.updateRow(row)

    del rows ,fc;

arcpy.AddMessage("3.进行差值操作");

inPointFeatures = "F:\py\jinan.gdb/city";

inBarrierFeature = "F:\py\jinan.gdb/barrier";

cellSize = 10000.0

arcpy.CheckOutExtension("Spatial")

outSplineBarriers = SplineWithBarriers(inPointFeatures, 'aqi1', inBarrierFeature, cellSize, 1);

tif = "pointraster.tif";

tif1 = "pointraster1.tif";

outSplineBarriers.save(tif);

arcpy.AddMessage("4.根据行政区边界图层剪切栅格")

outExtractByMask = ExtractByMask(tif, inBarrierFeature)

outExtractByMask.save(tif1)

arcpy.AddMessage("5.更新mxd");

mxdPath = mapPath + r"\pointraster1.mxd";

mxd = arcpy.mapping.MapDocument(mxdPath);

df = arcpy.mapping.ListDataFrames(mxd, "")[0];

for lyr in arcpy.mapping.ListLayers(mxd, "", df):

    arcpy.mapping.RemoveLayer(df, lyr);

addLayer = arcpy.mapping.Layer(mapPath + r"\pointraster1.lyr")

arcpy.mapping.AddLayer(df, addLayer, "BOTTOM")

arcpy.AddMessage("6.输出图片png");

fileName ="aqi.png"

df.extent = addLayer.getSelectedExtent()

arcpy.mapping.ExportToPNG(mxd, imagepath+"\\" + fileName , df, background_color="255,255,255", transparent_color="255,255,255",world_file=True);

arcpy.AddMessage("7.清理内存")

del mxd, addLayer,df,outSplineBarriers,inPointFeatures,inBarrierFeature