import arcpy
import csv
arcpy.env.overwriteOutput =True
Bus_Stops = r"D:\GIS\books\arcpy and arcgis - geospatial analysis with python\8662_ArcPyArcGIS_2\Data\SanFrancisco.gdb\SanFrancisco\Bus_Stops"
CensusBlocks2010 = r"D:\GIS\books\arcpy and arcgis - geospatial analysis with python\8662_ArcPyArcGIS_2\Data\SanFrancisco.gdb\SanFrancisco\CensusBlocks2010"
Inbound71 = r"D:\GIS\books\arcpy and arcgis - geospatial analysis with python\my work\chapter3.gdb\Inbound71"
Inbound71_400ft_buffer = r"D:\GIS\books\arcpy and arcgis - geospatial analysis with python\my work\chapter3.gdb\Inbound71_400ft_buffer"
Intersect71Census = r"D:\GIS\books\arcpy and arcgis - geospatial analysis with python\my work\chapter3.gdb\Intersect71Census"
bufferDist = 400
bufferUnit = "Feet"
lineNames = [('71 IB', 'Ferry Plaza'),('71 OB','48th Avenue')]
sqlTemplate = "NAME = '{0}' AND BUS_SIGNAG = '{1}'"
intersected = [Inbound71_400ft_buffer, CensusBlocks2010]
dataKey = 'NAME','STOPID'
fields = 'HOUSING10','POP10'
csvname = r'D:\GIS\books\arcpy and arcgis - geospatial analysis with python\my work\chapter3\Averages.csv'
def formatSQLMultiple(dataList, sqlTemplate, operator=" OR "):
'a function to generate a SQL statement'
sql = ''
for count, data in enumerate(dataList):
if count != len(dataList)-1:
sql += sqlTemplate.format(*data) + operator
else:
sql += sqlTemplate.format(*data)
return sql
def formatIntersect(features):
'a function to generate an intersect string'
formatString = ''
for count, feature in enumerate(features):
if count != len(features)-1:
formatString += feature + "
else:
formatString += feature + "
return formatString
def createResultDic(resultFC, key, values):
dataDictionary = {}
fields = []
if type(key) == type((1,2)) or type(key) == type([1,2]):
fields.extend(key)
length = len(key)
else:
fields = [key]
length = 1
fields.extend(values)
with arcpy.da.SearchCursor(resultFC, fields) as cursor:
for row in cursor:
busStopID = row[:length]
data = row[length:]
if busStopID not in dataDictionary.keys():
dataDictionary[busStopID] = {}
for counter,field in enumerate(values):
if field not in dataDictionary[busStopID].keys():
dataDictionary[busStopID][field] = [data[counter]]
else:
dataDictionary[busStopID][field].append(data[counter])
return dataDictionary
def createCSV(data, csvname, mode ='ab'):
with open(csvname, mode) as csvfile:
csvwriter = csv.writer(csvfile, delimiter=',')
csvwriter.writerow(data)
sql = formatSQLMultiple(lineNames, sqlTemplate)
print 'Process: Select'
arcpy.Select_analysis(Bus_Stops,
Inbound71,
sql)
print 'Process: Buffer'
arcpy.Buffer_analysis(Inbound71,
Inbound71_400ft_buffer,
"{0} {1}".format(bufferDist, bufferUnit),
"FULL", "ROUND", "NONE", "")
iString = formatIntersect(intersected)
print iString
print 'Process: Intersect'
arcpy.Intersect_analysis(iString,
Intersect71Census, "ALL", "", "INPUT")
print 'Process Results'
dictionary = createResultDic(Intersect71Census, dataKey, fields)
print 'Create CSV'
header = [dataKey]
for field in fields:
header.append(field)
createCSV(header,csvname, 'wb' )
for counter, busStop in enumerate(dictionary.keys()):
datakeys = dictionary[busStop]
averages = [busStop]
for key in datakeys:
data = datakeys[key]
average = sum(data)/len(data)
averages.append(average)
createCSV(averages,csvname)
print "Data Analysis Complete"
