2016-06-30 139 views
1

我想合成一個海岸線的預測()地圖與shape文件,其.prj文件中說:如何將我的cartopy映射與shapefile的投影相匹配?

GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984", 
SPHEROID["WGS_1984",6378137.0,298.257223563]], 
PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]] 

我的嘗試是:

import matplotlib.pyplot as plt 
import cartopy.crs as ccrs 
from cartopy.io import shapereader 

# set up a map with coastlines around Auckland: 
plt.figure(figsize=(10, 10)) 
platecarree = ccrs.PlateCarree(globe=ccrs.Globe(datum='WGS84')) 

ax = plt.axes(projection=platecarree) 
extent = [174.25, 175.25, -37.5, -36.5] 
ax.set_extent(extent) 
ax.coastlines('10m',color='red') 

# read in shapefile and plot the polygons: 
shp2 = shapereader.Reader('auckland_geology_wgs84gcs.shp') 
formations = shp2.records() 

for formation in formations: 
    # plot water blue, and all other rocks yellow 
    if formation.attributes['MAIN_ROCK'] == b'        ': 
     ax.add_geometries(formation.geometry, ccrs.PlateCarree(),facecolor='blue',alpha=.1) 
    else: 
     ax.add_geometries(formation.geometry, ccrs.PlateCarree(), facecolor='yellow',alpha=.1) 
plt.show() 

我試圖給地球我的platecarree定義中的參數是prj文件的半徑和逆平坦度,但是如果我設置或甚至改變這些數字,我沒有看到輸出的任何更改。

此外,在add_geometries調用中,使用定義的「platecarree」投影(以WGS84調用全球)作爲crs,我的輸出爲空白。

原樣,結果在我看來就像a projection mismatch

回答

1

我試圖重現使用QGIS和數據從自然地球(10米海岸線)下載,並從GADM(NZ ADM0級)你的問題。看起來NE10m海岸線是罪魁禍首! GADM與您的地質層完美對齊,而NE10m關閉(和變形)。 screenshot of QGIS with Geological map & coastlines