栅格：如何使用python获得经纬度的海拔？

Question

I also posted this question in the GIS section of SO. As I'm not sure if this rather a 'pure' python question I also ask it here again.

I was wondering if anyone has some experience in getting elevation data from a raster without using ArcGIS , but rather get the information as a python list or dict ?

I get my XY data as a list of tuples.

I'd like to loop through the list or pass it to a function or class-method to get the corresponding elevation for the xy-pairs.

I did some research on the topic and the gdal API sounds promising. Can anyone advice me how to go about things, pitfalls, sample code? Other options?

Thanks for your efforts, LarsVegas

Answer 1

I recommend checking out the Google Elevation API

It's very straightforward to use:

http://maps.googleapis.com/maps/api/elevation/json?locations=39.7391536,-104.9847034&sensor=true_or_false

{
   "results" : [
      {
         "elevation" : 1608.637939453125,
         "location" : {
            "lat" : 39.73915360,
            "lng" : -104.98470340
         },
         "resolution" : 4.771975994110107
      }
   ],
   "status" : "OK"
}

note that the free version is limited to 2500 requests per day.

Answer 2

We used this code to get elevation for a given latitude/longitude (NOTE: we only asked to print the elevation, and the rounded lat and long values).

import urllib.request
import json
lati = input("Enter the latitude:")
lngi = input("Enter the longitude:")

# url_params completes the base url with the given latitude and longitude values
ELEVATION_BASE_URL = 'http://maps.googleapis.com/maps/api/elevation/json?'
URL_PARAMS = "locations=%s,%s&sensor=%s" % (lati, lngi, "false")
url=ELEVATION_BASE_URL + URL_PARAMS
with urllib.request.urlopen(url) as f:
response = json.loads(f.read().decode())    
status = response["status"]
result = response["results"][0]
print(float(result["elevation"]))
print(float(result["location"]["lat"]))
print(float(result["location"]["lng"]))

Answer 3

Have a look at altimeter a wrapper for the Google Elevation API

Answer 4

Here is the another one nice API that I`v built: https://algorithmia.com/algorithms/Gaploid/Elevation

import Algorithmia

input = {
    "lat": "50.2111",
    "lon": "18.1233"
}
client = Algorithmia.client('YOUR_API_KEY')
algo = client.algo('Gaploid/Elevation/0.3.0')
print algo.pipe(input)