python——csv檔案轉換為shp
阿新 • • 發佈:2018-12-24
學地信的經常會有這樣的需求,即將csv格式的檔案轉換為shapefile格式載入到arcMap中進行顯示與分析,arcMap本身提供了這樣的功能,即
檔案->新增資料->新增XY資料:選擇檔案路徑,指定X欄位(longitude)、Y欄位(latitude)即可,預設座標系為WGS84座標系。
arcMap的這個功能非常方便,但因為我的資料量較大,有接近100萬條資料,故通過程式碼進行格式轉換效率更高點。
下面的程式碼參考如下連結:Using pyshp to convert .csv file to .shp?
需要用到pyshp模組、csv模組、codecs模組,pip install 安裝即可。
下面貼上程式碼:
目前只能轉換point型別資料
#-*-coding:utf-8-*-
import shapefile as shp
import csv
import codecs
import os
def trans_point(folder, fn, idlng, idlat, delimiter=','):
# create a point shapefile
output_shp = shp.Writer(shp.POINT)
# for every record there must be a corresponding geometry.
output_shp.autoBalance = 1
# create the field names and data type for each.you can omit fields here
# output_shp.field('id','N') # number
output_shp.field('longitude', 'F', 10, 8) # float
output_shp.field('latitude', 'F', 10, 8) # float
output_shp.field('locname','C',100) # string, max-length
# access the CSV file
with codecs.open(folder + fn, 'rb', 'utf-8') as csvfile:
reader = csv.reader(csvfile, delimiter=delimiter)
# skip the header
next(reader, None)
#loop through each of the rows and assign the attributes to variables
for row in reader:
# idx = row[0]
locname= row[1]
lng= float(row[idlng])
lat = float(row[idlat])
print lng, lat
# create the point geometry
output_shp.point(lng, lat)
# add attribute data
output_shp.record(lng, lat, locname)
output_shp.save(folder + "%s.shp"%fn.split('.')[0]) # save the Shapefile
if __name__ == '__main__':
folder = 'C:\Users\MaMQ\Desktop' + os.sep
fn = 'test.csv'
trans_point(folder, fn, 2, 3)
示例資料
id | locname | x | y |
---|---|---|---|
1 | Haryana, Haryana, India | 76.9806 | 29.6161 |
2 | Mumbai, Maharashtra, India | 72.8258 | 18.975 |
結果